Dissertations / Theses: 'Penguins'

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Liljesthröm, Marcela. "Avian predation at a Southern Rockhopper Penguin Colony on Staten Island, Argentina /." Electronic version (PDF), 2005. http://dl.uncw.edu/etd/2005/liljesthromm/marcelaliljesthrom.pdf.

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Smith, Diane Lauren. "Penguin parenting : assortative mating, nest attendance and sex-specific chick provisioning in the African Penguin (Spheniscus demersus)." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/d1019993.

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Animal behaviour is especially sensitive to environmental variability and prey availability during the breeding season, and this is particularly true for non-volant, central place foragers such as the endangered African Penguin (Spheniscus demersus). Individual sex and morphology, as well as the level of assortment within mated pairs can influence both the behaviour and the reproductive success of species exhibiting biparental care. This study made use of a large biometric database and nest attendance video footage to determine the influence of intrinsic (assortative mating, brood size and chick age) and extrinsic (environmental conditions, anthropic disturbance) factors on breeding behaviour and performance of African Penguins on Bird Island, Algoa Bay, during peak breeding (March - July) in 2013. While sexual dimorphism in African Penguins is subtle, the colony-specific discriminant functions presented here provide an accurate sexing tool when only bill and flipper length are available. Despite the premise that selection of a large, high-quality mate in this longlived, monogamous seabird governs lifetime fitness, only low levels of assortative mating were found, and this only for earlier breeders, when larger females (but not males) bred. The 2013 season was a particularly successful one, coinciding with above-average sardine and anchovy abundance, and almost 80 percent of monitored nests were double-brooded, with very low levels of mortality. A- and B-chicks of double broods and singleton chicks grew at similar rates and exhibited similar body condition indices. In these conditions, chick developmental rates were independent of parental size, assortment or provisioning behaviour. Females raising a double brood were significantly lighter and in poorer body condition than those raising a single chick, although the same trend was not evident in males. Offspring sex ratio in 2013 (2.27:1) favoured male chicks, suggesting that there is potential to over-produce the larger sex when resources are plentiful. Peak nest arrival and departure times of parents did not change over the course of monitored breeding attempts (March-June), nor were they different for disturbed and undisturbed nests or for a single or double brood. The increase in CCTV-observed provisioning rate as chicks grew larger was best explained by brood size, at-sea chlorophyll a concentration, and maximum air temperature, but was unrelated to parental morphology or assortative index. Importantly, parental absenteeism commenced earlier and was markedly greater in nests frequently handled by researchers than in undisturbed nests. Both the time spent together by parents, and absenteeism were measurably affected by maximum afternoon air temperatures, the effects of which are expected to be exacerbated by poorer foraging conditions and climate change. A third of manually-monitored nests shared chick-guarding duties unequally, although this phenomenon was independent of parental sex or morphology. The adaptive benefits of mating patterns and division of labour during chick-rearing may only become apparent in a year of below-average food availability and it is highly recommended that this study be repeated in a year of scarce food resources. These findings augment past foraging ecology studies and demonstrate that investigator disturbance and environmental conditions can affect the nesting behaviour of this highly threatened seabird.

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Mattern, Thomas, and n/a. "Marine ecology of offshore and inshore foraging penguins : the Snares penguin Eudyptes robustus and Yellow-eyed penguin Megadyptes antipodes." University of Otago. Department of Zoology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070502.150734.

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Seabirds have become adapted for foraging in an oceanic environment that can be highly dynamic. Oceanographic processes determine the spatial distribution of seabird prey, while seasonality often has a temporal influence on prey availability. In penguins, these factors are reflected in the different species� foraging strategies. Penguins can broadly be categorized as inshore foragers that live in subtropical to temperate regions and profit from a stable food supply throughout the year close to their breeding sites, and offshore foragers that breed in a pelagic environment at higher latitudes where oceanographic processes and seasonality create much more dynamic, temporally limited prey situations. In this light, offshore foragers can be expected to be much more flexible in their foraging behaviour so as to quickly respond to changes in a dynamic marine environment, while inshore foragers are more likely to exhibit predictable foraging patterns. I examined the foraging ecology of two New Zealand penguin species - the offshore foraging Snares penguin Eudyptes robustus and the inshore foraging Yellow-eyed penguin Megadyptes antipodes and how their foraging strategies reflect an adaptation to the marine environment they exploit. Diet composition of breeding Snares penguins (incubation and early chick-guard) was determined using the water-offloading method. Before the chicks hatched, the penguins generally brought little food back from their long foraging trips. During chick-guard, the stomach contents comprised mainly of crustaceans (~55%), fish (~24%) and cephalopods (~21%). However, the presence at times of many fish otoliths and squid beaks suggests that the latter two prey classes may play an even more important role in the adults� diet than the simple percentages based on mass suggest. The penguins� nesting routines were strongly synchronised between the years and correlated with the onset of the spring planktonic bloom. Using GPS data loggers and dive recorders I found that during the incubation phase, male penguins that performed long (ca. 2 week) foraging trips exhibited a strong affinity to forage in the Subtropical Front some 200 km east of the Snares. At that stage (late mid-October) the front featured elevated chlorophyll a concentrations, a pattern that can be observed every year. Thus, it seems that the front represents a reliable and predictable source of food for the male penguins. After the males returned, the female penguins also performed long foraging trips (<1 week) but never reached the front, primarily because they had to time their return to the hatching of their chicks. After the chicks had hatched, the female Snares penguins were the sole providers of food. At this stage, the penguins performed short foraging trips (1-3 days) and foraged halfway between the Snares and Stewart Island (ca. 70-90 km north of the Snares), where nutrient-rich coastal waters flow eastwards to form the Southland Current. The penguins concentrated their diving effort in these waters, underlining the importance of the warm coastal waters as a food source for breeding Snares penguins. However, diving behaviour between 2003 and 2004 differed with penguins searching for prey at greater depths in the latter year. This underlines the Snares penguins� behavioural flexibility in response to a changing marine environment. The Yellow-eyed penguins as typical inshore foragers showed very consistent foraging patterns at all stages. GPS logger deployments on penguins at Oamaru revealed that the birds foraged almost exclusively at the seafloor and targeted specific areas that featured reefs or epibenthic communities. As a result, the penguins� at-sea movements appeared conservative and at times almost stereotypic. Nevertheless, a comparison of Yellow-eyed penguins breeding on the adjacent Codfish and Stewart islands revealed a degree of plasticity in the species� foraging behaviour. Birds from Codfish Island extended their foraging ranges considerably and switched from primarily bottom to mid-water foraging during the post-guard stage of breeding. It seems likely that this switch is a result of enhanced feeding conditions (e.g. increased prey abundance/quality) in an area further away from the island, but the time required to get there renders this strategy not viable when chicks are small and need to be guarded and fed on a daily basis. As such, the change of behaviour represents a traditional pattern rather than a dynamic response to a sudden change in the marine environment. In comparison, penguins from Stewart Island showed consistent foraging patterns during all stages of breeding. Given the high levels of chick starvation on Stewart Island, the lack of plasticity in foraging behaviour is surprising and might indicate that Yellow-eyed penguins find it difficult to react quickly to a sub-optimal food situation. Overall, it seems that Yellow-eyed penguins show a specialisation for a consistent benthic environment and, thus, lack the behavioural flexibility apparent in Snares penguins, which find their food in a changing pelagic marine environment.

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Wilson, Rory Paul. "Breeding Jackass Penguins as pelagic predators." Doctoral thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/17653.

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Bibliography: pages 187-191.
The foraging of breeding Jackass Penguins Spheniscus demersus was studied in and around southwestern Cape Province, Saldanha Bay (33⁰ S, 18⁰ E), South Africa. Penguins are difficult to observe at sea. Hence, I devised a number of new techniques for studying the foraging behaviour of Jackass Penguins at sea. I built electronic and autoradiographic remote-sensing devices to measure swimming speed, distance travelled and time spent at each depth by foraging Jackass Penguins. Penguin swimming speed was reduced in proportion to the cross-sectional area of the devices, and results derived from birds wearing the devices had to be interpreted accordingly. Penguins do not regurgitate their stomach contents when handled, so I constructed a wet-offloading stomach pump which extracted 100% of the stomach contents. Using this pump, I determined that the rate of digestion of fish and squid by Jackass Penguins differed. Care is needed in diet interpretations where both fish and squid are major food items.

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Yoda, Ken. "Behavioural decisions of provisioning Adélie penguins." 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/149126.

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Moon, Katherine Louise. "Do terrestrial ectoparasites disperse with penguins?" Phd thesis, Canberra, ACT : The Australian National University, 2017. http://hdl.handle.net/1885/144227.

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Dispersal plays a critical role in evolution. Rare long-distance movements can lead to allopatric speciation, whereas frequent movements can facilitate gene flow among disjunct populations and prevent divergence. Dispersal between populations of a species may be difficult to observe directly, and is often inferred from indirect measures such as species occurrence data. Increasingly, however, high resolution genomic data are being used to clarify dispersal and gene flow, in many cases contradicting past assumptions. Islands are excellent model regions for investigating dispersal as they offer replicated habitats with clear geographic boundaries. The sub-Antarctic comprises some of the most geographically isolated island ecosystems in the world, representing an ideal model system for assessing the evolutionary consequences of long-distance dispersal. Strong winds, circumpolar oceanic currents, and extreme climatic cycles are thought to have effectively isolated many sub-Antarctic ecosystems, but a growing body of molecular evidence is beginning to question this rhetoric, with numerous species showing connectivity across the region. Connectivity patterns are, however, complex and are not always predictable from an organism’s inferred dispersal capacity. With environmental change placing unprecedented pressure on isolated ecosystems, there is a pressing need for improved understanding of dispersal processes and population connectivity via genomic analyses of diverse taxa. A number of sub-Antarctic species exhibit gene flow across the region despite lacking active long-distance dispersal capabilities. Brooding, sedentary crustaceans have, for example, rafted on buoyant kelp across thousands of kilometres of open ocean in the sub-Antarctic. The close symbiotic or parasitic relationships that such species maintain with the kelp has resulted in whole communities dispersing together. Indeed, active dispersal is often limited in parasites, which can depend almost entirely on mobile hosts for long-distance movement. A parasite that is unable to travel far with its host would, therefore, be expected to show considerable phylogeographic structure. For example, penguins primarily travel underwater but are hosts to terrestrial ectoparasites (most commonly ticks - Ixodes spp.) when they come ashore to breed. Aquatic host movements may represent a challenge to the survival of penguin ticks, restricting gene flow across their range. This thesis first reviews connectivity patterns and challenges throughout the sub-Antarctic, and then uses a multidisciplinary approach (genomic and physiological data) to test whether some terrestrial parasites (ticks: Acari) are able to travel long distances at sea with their aquatically dispersing hosts (penguins). Results indicate that penguin ticks are physiologically resilient, and may be capable of surviving the conditions faced during aquatic penguin movements between colonies. However, these movements appear to be too sporadic to maintain gene flow across the ticks’ ranges, resulting in broad-scale geographic structure. In contrast, movement on fine scales (within colonies) is inferred – based on lack of genomic structure – to be common, possibly facilitated by social interactions of hosts. These results emphasise the important role of dispersal in isolated regions for range expansion and diversification, and highlight the adaptability of parasites to their hosts’ environments.

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Booth, Jenny Marie. "Trophic ecology of breeding northern rockhopper penguins, Eudyptes Moseleyi, at Tristan da Cunha, South Atlantic Ocean." Thesis, Rhodes University, 2012. http://hdl.handle.net/10962/d1005476.

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Northern Rockhopper penguin populations, Eudyptes moseleyi, are declining globally, and at Tristan da Cunha have undergone severe declines (> 90% in the last 130 years), the cause(s)of which are unknown. There is a paucity of data on this species in the South Atlantic Ocean, therefore their trophic ecology at Tristan da Cunha was studied, specifically focusing on diet, using stomach content analysis and stable isotope analysis (SIA), in conjunction with an analysis of diving behaviour, assessed using temperature-depth recorders. In order to evaluate the influence of gender on foraging, a morphometric investigation of sexual dimorphism was confirmed using molecular analysis. Additionally, plasma corticosterone levels were measured to examine breeding stage and presence of blood parasites as potential sources of stress during the breeding season. Northern Rockhopper penguins at Tristan da Cunha displayed a high degree of foraging plasticity, and fed opportunistically on a wide variety of prey, probably reflecting local small-scale changes in prey distribution. Zooplankton dominated (by mass) the diet of guard stage females, whereas small meso-pelagic fish (predominantly Photichthyidae)dominated diet of adults of both sexes in the crèche stage, with cephalopods contributing equally in both stages. Adults consistently fed chicks on lower-trophic level prey (assessed using SIA), probably zooplankton, than they consumed themselves indicating that the increasing demands of growing chicks were not met by adults through provisioning of higher- quality prey. SIA also indicated that adults foraged in different oceanic water masses when feeding for self-maintenance and for chick provisioning, thus temporally segregating the prey consumed for different purposes. It is possible that adults ‘selected’ these higher quality prey for themselves, or this may be a reflection of opportunistic behaviour. At Tristan da Cunha sexual dimorphism was observed in culmen dimensions (length, depth, width), with males having larger beaks and feeding on larger individuals of squid and fish than females. No sexual segregation in terms of foraging habitat (i.e. different water masses, based on ð¹³N or trophic level ð¹⁵N) during the breeding season or pre-moult period was revealed through SIA, and stomach content analysis revealed no sexual differences in prey species targeted. The results of SIA of feathers indicate that during the pre-moult period birds foraged in different water masses than during the breeding period. The fact that throughout the breeding season birds foraged in similar habitats suggests no intra-specific competition, despite both sexes feeding on the same prey.Birds were generally diurnal, daily foragers (12 – 16 hr trips), with extended trips (maximum duration 35.5 hours) and nocturnal diving recorded in a few individuals. Birds dived well within their physiological limits, predominantly utilising the upper 20m of the water column, employing two different strategies to target different prey items. Long, deep (30 – 40 m), energetically costly dives were performed when targeting energy-rich prey (fish), and a greater number of shorter, shallower (5 – 20 m), energy-efficient dives were performed when targeting prey with a lower energy content (zooplankton). More than half of the sampled study population were infected with the intra-cellular blood parasite Babesia, but infection showed no relationship to body mass, corticosterone levels or breeding success. Fasting birds showed no signs of elevated corticosterone levels, suggesting they had acquired sufficient fat reserves prior to breeding. Failed breeders did not exhibit elevated corticosterone levels. Tristan skuas, Catharacta antarctica hamiltoni, were observed to be a significant cause of egg and chick mortality. The absence of sex-based differences in foraging, and the absence of any signs of stress in relation to body mass, presence of Babesia or breeding stage, suggest that there are no obvious signs of high levels of stress or food limitations during breeding at Tristan da Cunha.

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Ralph, Mark Shaun. "Aspects of the breeding biology of the African penguin on Bird Island, Algoa Bay." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/840.

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It is important to the survival of the Africa Penguin (Spheniscus demersus) population that breeding at the nest site is successful and that large numbers of chicks are fledged into the breeding population. Nest distribution on Bird Island is not random and locality preferences for breeding exist. Although it seems that sufficient area exists on Bird Island for penguin nests, it can hardly be considered as suitable to optimise breeding. During prolonged heat conditions, breeders relocated to nest sites that were sheltered. Nests that were below ground in burrows was the only habitat that did not suffer nest desertion whilst all the other habitat types (including those that were sheltered) experienced 2-3 fold declines in nest numbers. Nests density and the selection of suitable nest sites are significantly influenced by the stage of breeding that the majority of birds are in, yet nests that are shaded, well-ventilated and protected seem to be the most preferred sites for breeding. Adults that attempt to breed are considered then to be in a healthy condition and will usually lay a double clutch (Randell 1983). The frequency of double clutches being laid during the peak breeding attempt was significantly higher compared to the replacement one. Breeding failure was fairly similar to breeding success during the incubation stage for nests with double clutches however, was substantially higher in single clutches. The growth rate of chicks was best fit to the von Bertalanffy growth curve in 90 percent of the cases. The overall growth rate of chicks from double broods was faster than from single broods, however was not significant. A-chicks maitain a high growth rate until they fledged. Yet, the sibling B-chick recorded the lowest growth rate of the successfully fledged chicks and up to until day 30 recorded a similar weight to those chicks that failed to fledge. Contrary to findings of Randall (1983), chicks from single broods delayed fledging, recorded lowest overall growth rates and experienced the greatest weight loss of all groups, yet fledged successfully. In order for chicks to fledge successfully, they needed to obtain a weight of 1060 g before day 30.5 in their growth cycles to avoid death due to startvation later on. Single chicks that are raised from a double cluth, fledged more other than chicks raised from a single clutch. Unfit or ill-adapted breeders that are marginal in the capabilities of raising offspring, already manifest in a small clutch size and offspring unable to obtain adequate weights during the initial stages of growth.

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Black, Caitlin Emily. "Variation in the phenology of Pygoscelis penguins." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:00c306b4-f7c4-4f11-8749-1e3ae118746b.

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Variation in phenology is linked to the timing of environmental variables and influences survival at both the individual and colony level. Therefore, understanding a species' annual cycle is vital to its ecology and conservation. By reviewing literature on Pygoscelis penguin phenology in Chapter 1, I identify major gaps, both spatially and temporally, in our knowledge of the timing of events in the three species (Adeélie, Pygoscelis adeliae; chinstrap, and Pygoscelis antarctica; gentoo, Pygoscelis papua): particularly, 1) during the guard phase, 2) their behaviour in winter, 3) the phenology of colonies inhabiting locations away from scientific bases, and 4) the general phenology of chinstrap penguins. Chapter 2 assesses which time-lapse camera methods are most relevant to seabird research, highlighting the capabilities and limitations of cameras in past studies and how they may be best applied to future research. Chapter 3 examines the timing of the guard phase in gentoo penguins and how chick aggregation behaviours vary across several sites. Chapters 4 and 5 show variation in winter abundance at breeding sites in both gentoo and Adélie penguins related to abiotic factors and colony location. Lastly, Chapter 6 fills in gaps in the known timing and duration of phenology events in gentoo and chinstrap penguins across their full latitudinal ranges, while relating these timings to chick survival. In the conclusion, I summarize the main findings of the thesis, focusing on three major themes that were observed across the four data chapters and their implications: 1) behaviours are not consistent across colony locations 2) nor between years, and these behaviours depend on 3) local environmental conditions. I then synthesize these empirical findings from each of these chapters, discuss the implication of these findings to ecological theory and conservation policy, highlight some of the limitations of these studies, and recommend possibilities for future research.

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Ando, Tatsuro, and n/a. "New Zealand fossil penguins : origin, pattern, and process." University of Otago. Department of Geology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080204.140701.

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Penguins are middle- to large-sized sea birds and are widely distributed in the Southern Hemisphere. They have completely lost the capability for the aerial flight, but are highly efficient wing-propelled swimmers and divers. They have a long fossil record over 60 million years, and their origin could possibly extend back to the late Cretaceous. This study aims to elaborate the course of penguin evolution and driving force of changes based on fossil records of penguins. Numerous fossil penguin specimens have been collected and studied from New Zealand, Antarctica, South America, Australia, and Africa. Studies on fossil penguins have spanned about 150 years history since Huxley (1859). Previous works on fossil penguins have achieved excellent results, but at the same time, left considerable confusion on taxonomy and anatomical interpretation, mainly because of the poor nature of the penguin fossils in early studies. Examination of newly found materials and updated evaluation of previously studied materials are needed, using modern methods. During about 150 years of fossil penguins study since Huxley1859, more than 40 genera and 70 species have been described. The number of specimens listed in the published literature amounts to more than 1300. Chapter II reviews all those fossil penguins in a summarised and consistent style, aiming to present the taxonomy used in this study as a primary and essential resource for research. The chapter also provides other information on fossil penguins, such as geological data and an assessment of the skeletal association of the specimens referred to a species. Chapter III introduces the osteology of penguins, by describing and comparing the skeletal characteristics and variation of both extant and fossil species. Though previous works on penguins osteology are extensive, the interpretation of the homology, and resulted terminology, are occasionally inappropriate, or incorrect, because of the highly-specialised structure. Many of the new, yet undescribed, fossils prompt a comprehensive update of those previous studies, to understand the nature of morphological variation in penguins, and to correct or clarify confusion in previous works. The New Zealand fossil penguin fauna is one of the most significant for fossil penguin studies, but there are many undescribed fossil penguin specimens. Chapter IV provides accounts of such materials. Chapter IV also reviews previously-described New Zealand fossil penguins, usually re-evaluated using new materials. This chapter includes reassessment of the controversial, first-described fossil penguin Palaeeudyptes antarcticus, description of an enigmatic new species (Pakudyptes hakataramea gen. et sp. nov.) which could elucidate the evolutionary pattern of the penguin wing, description of new materials of Platydyptes revealing a unique structure and functional interpretation, and redescriptions with functional interpretation of Pachydyptes and Archaeospheniscus. Published relationships within penguins have not been adequately discussed but stated within rather rough frameworks, so that the relationships within penguins were unclear. Chapter V provides an explicit framework for the phylogeny of penguins. Osteology-based cladistic analysis was performed to seek out the relationships within penguins, using observations on both extant and fossil penguins. There are several important grades in penguin history, which are structurally distant from each other. Results also agree with the published views in which the extant penguins form a rigid group, but Simpson�s subfamily groupings are only partly supported. A postulated phylogenetic tree includes all known fossil penguin taxa including un-named ones. Chapter VI, as a synthesis of contents of previous chapters, provides a broad interpretation of penguin evolution through the Cenozoic: origin, body size increase, demise of 'giant penguins', and the emergence of modern penguins. The chapter gives a global picture of the interaction of penguins, pinnipeds, cetaceans, and temperature and sea-level change. Two main sections are: 'Origin of penguins' and 'Evolutionary process of penguins.' The loss of aerial flight and increase of body size were possibly triggered by the K/T mass extinction event which drastically reduced the predatory pressure for early penguins. The 'giant penguins' survived until the Late Oligocene but declined as the oceans modernised, and new forms of whales with advanced feeding function appeared. There is controversy about appearance of modern penguins. The fossil-based hypothesis (relatively recent origin for crown-penguins) contradicts the molecular-based one (ancient origin for crown penguins), though 'hard evidence' at present does not easily refute either hypothesis.

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Ninnes, Calum Edward. "Behavioural Endocrinology of Breeding Adelie Penguins (Pygoscelis adeliae)." The University of Waikato, 2008. http://hdl.handle.net/10289/2473.

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Measuring hormonal changes is vital for understanding how the social and physical environment influences behaviour, reproduction and survival. Various methods of hormone measurement exist, potentially explaining variation in results across studies; methods should be cross validated to ensure they correlate. I directly compare faecal and plasma hormone measurements (Chapter 2), and use the most suitable endocrine measure to test the Darling hypothesis (Chapter 3) - that breeding is hastened and synchronized in larger colonies due to increased social stimulation (mediated by the endocrine system). Blood and faecal samples were simultaneously collected from individual Adelie penguins (Pygoscelis adeliae) for comparison, and assayed for testosterone and corticosterone (or their metabolites). Sex differences and variability within each measure, and correlation of values across measures were compared. For both hormones, plasma samples showed greater variation than faecal samples. Males had higher corticosterone levels than females, but the difference was only significant in faecal samples. Plasma testosterone, but not faecal testosterone, was significantly higher in males than females. Correlation between sample types was poor overall, and weaker in females than in males; perhaps because measures from plasma represent hormones that are both free and bound to globulins, whereas measures from faeces represent only the free portion. Faecal samples also represent a cumulative measure of hormones over time, as opposed to a plasma 'snapshot' concentration. Faecal sampling appears more suitable for assessing baseline hormone levels. In the second study I examined, over two seasons, whether the timing of breeding varied with colony size; larger colonies present occupants with higher levels of social stimulation and are predicted to show earlier, more synchronous breeding. Baseline faecal hormone levels throughout the breeding season, and survival, were measured to investigate possible proximate and ultimate mechanisms for the results. The influence of environmental variability was examined, by relating the timing of breeding, survival, and endocrine changes to sea ice conditions. Colony size did not influence the timing or synchrony of breeding, survival, or hormone levels within years; perhaps because colonies in an Adelie rookery are not independent from the 'social environment' of adjacent colonies. Across years, synchrony in the smaller rookery was higher than in the larger rookery. The scale of these comparisons may exceed the applicability of the Darling hypothesis. Therefore, no support was found for the Darling hypothesis, at the colony or rookery level, in this species. Higher corticosterone metabolite and lower sex hormone levels in the first season correlated to later breeding and lower survival compared to the second season. This is likely due to the persistence of extensive sea ice conditions late into the first season. Researchers should take care in selecting the most appropriate method of hormone measurement for their question. Future studies testing the Darling hypothesis must carefully select their definition of a colony (i.e. a truly isolated social unit) and the scale at which the hypothesis is tested. Combining endocrine measurements with behavioural, survival, and environmental information allows for a more comprehensive interpretation of animal ecology.

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Sidhu, Leesa A. Physical Environmental &amp Mathematical Sciences Australian Defence Force Academy UNSW. "Analysis of recovery-recapture data for little penguins." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Physical, Environmental and Mathematical Sciences, 2007. http://handle.unsw.edu.au/1959.4/38738.

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This thesis analyses yearly mark-recapture-recovery information collected over a 36- year period, from 1968 to 2003, for 23 686 flipper-banded Little Penguins Eudyptula minor of Phillip Island, in south-eastern Australia. Such a long-term data set is extremely rare for any species. Few studies of any animal have been able to model age dependence for the survival, recapture and recovery probabilities simultaneously. I successfully apply such a modelling scheme and obtain biologically realistic age structures for the parameters. I also provide illustrations of erroneous results that may arise when analyses fail to consider simultaneous age dependence, or fail to detect annual variations that may mask age dependence. I obtain a low survival estimate of 17% in the first year of life, increasing to 71% in the second year, and around 80% thereafter, and declining gradually after age nine years. First-year survival increases with number of chicks fledged per pair, increases with annual average fledging weight and decreases with mean laying date. An increase in first-year survival is associated with warmer sea surface temperatures in the summer and autumn of the previous year, which agrees with biological considerations. Irrespective of this inter-year variation, birds born early in the breeding season, relative to the rest of their cohort, have greatly enhanced first-year survival, when compared to birds born late in that season. Fledglings survive better in years in which the mean fledgling weight is higher, and fledglings of above average weight have a better chance of survival than their underweight counterparts. I next analyse seven years of recapture data from a separate experiment studying the effect of banding on adult Little Penguins. In the year following marking, the i survival probability of banded birds is 6% lower than that of unbanded birds, while in subsequent years the survival is 4% lower for banded birds. Band loss is negligible. Finally, I compare the survival estimates for Phillip Island with those obtained for a six-year study in New Zealand. While first-year survival is significantly higher for New Zealand, there is a marked decline over time, coinciding with an increase in population size.

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Sutton, Grace. "Fine-scale foraging movements and energetics in penguins." Thesis, La Rochelle, 2021. http://www.theses.fr/2021LAROS031.

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Quantifier les interactions prédateur-proie peut être difficile sur le plan logistique, en particulier dans les environnements marins. Cependant, il est essentiel de prédire comment les individus réagissent aux changements dans la disponibilité des proies, un facteur important dans l'évaluation de l'impact du changement climatique. Dans la présente étude, une combinaison de caméras, d'accéléromètres, d'enregistreurs de plongée et de GPS a été utilisée pour déterminer les facteurs influençant l'effort et l'efficacité de la recherche alimentaire chez les manchots. Celles-ci ont été étudiées chez 3 espèces : le manchot pygmée (Eudyptula minor), le manchot du Cap (Spheniscus demersus) et le gorfou macaroni (Eudyptes chrysolophus). Chez chaque espèce, les patchs de proies dictaient le mouvement tridimensionnel des manchots dans la colonne d'eau. L'effort de recherche de nourriture chez le manchot pygmée était influencé par l'abondance des proies, et non par le type de proie. L'accélération moyenne des manchots pygmées a été examinée en tant qu'indice d'effort et s'est avérée fortement corrélée aux taux de dépense énergétique déterminés à partir d'eau doublement marquée. L'apprentissage automatique a été utilisé pour détecter les captures de proies qui ont été validées à l'aide de caméras vidéo chez le manchot du Cap et le gorfou macaroni. Il a été constaté que les manchots du Cap présentaient des plongées pélagiques et une grande proportion de plongées benthiques. Les plongées benthiques étaient plus coûteuses mais plus fructueuses que les plongées pélagiques, indiquant un compromis entre l'effort et le succès. Les gorfous macaronis ont affiché un comportement spécifique à leurs proies, plongeant profondément lorsqu'ils se nourrissent de krill et effectuant des plongées peu profondes lorsqu'ils ciblaient des poissons. Cet ensemble de travaux met en évidence l'effet des patchs de proies et les facteurs de variabilité du comportement de recherche alimentaire
Quantifying predator-prey interactions can be logistically difficult, especially in marine environments. However, it is essential to predict how individuals respond to changes in prey availability, an important factor in assessing the impact of climate change. In comparison to flying seabirds, penguins (Family: Spheniscidae) experience greater constraints when breeding due to restrictions in foraging range. As such, this group of seabirds are considered good indicators of local ecosystem health. Animal-borne video cameras have made it possible to observe behaviour in response to prey field. In the present study, a combination of animal-borne video cameras, accelerometers, dive recorders and GPS were used to determine the factors influencing foraging effort and efficiency in penguins. These were investigated in 3 species: 1) little penguin, Eudyptula minor; 2) African penguin, Spheniscus demersus, 3) Macaroni penguin, Eudyptes chrysolophus. In each species, the immediate prey field dictated the 3-dimensional movement in the water column. Foraging effort in little penguins was influenced by the abundance of prey, not prey type. The mean body acceleration of little penguins was examined as an index of effort and was found to be highly correlated to energy expenditure rates determined from doubly-labelled water. Machine learning was used to detect prey captures which were validated using video cameras in African and Macaroni penguins. It was found that African penguins exhibited pelagic dives and a large proportion of successful benthic dives. Benthic dives were costlier but more successful than pelagic ones, indicating a trade-off between effort and success. Macaroni penguins displayed prey-specific behaviour, diving deep when foraging on subantarctic krill (Euphausia vallentini) and completing shallow dives when targeting juvenile fish.This body of work highlights the effect of prey field and the drivers of variability in foraging behaviour

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Brown, Christopher Raymond. "Ecological energetics of Eudyptes penguins at Marion Island." Doctoral thesis, University of Cape Town, 1987. http://hdl.handle.net/11427/7594.

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Includes bibliographies.
Macaroni Penguins (Eudyptes chrysolophus) and Rockhopper Penguins (E. chrysocome) breed sympatrically at Marion Island in the sub-Antarctic, where they account for a substantial proportion of the avian biomass breeding at the island. This thesis documents the energy requirements of the two species during their respective breeding and moulting cycles at the island. Resting metabolic rates, calculated from lowest, stable rates of oxygen consumption over 24 h, averaged 25 % greater than basal metabolic rates predicted from allometric equations. Body temperatures of the penguins and the relationships between metabolic rates and temperature were investigated over a range of -10°C to 25°C. Lower critical temperature of Rockhopper Penguins was between 0°C and 5°C, but that of Macaroni Penguins could not be clearly ascertained. Measured metabolic rates of other species of penguins are reviewed and intra- and inter-specific differences in metabolic rates are discussed. In contrast to most penguins measured, individuals maintained in zoos or held in captivity for long periods had metabolic rates lower than predicted basal levels.

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Broni, Stephen Christopher. "Penguins and purse-seiners : competition or co-existence?" Master's thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/7611.

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Bibliography: leaves 110-124.
The relationships between the pelagic purse-seine fishery and Jackass penguins (Spheniscus demersus) were investigated at Saldanha Bay, on the south-western coast of South Africa, between December 1982 and August 1983. The distribution at sea and the foraging behaviour of Jackass Penguins were examined by running standard transects with a sail boat in waters close to the birds' breeding islands. The use of a sail boat permitted close observation of foraging penguins with minimal disturbance. Penguin numbers at sea were lowest in December, when birds were confined to the breeding islands during moulting and were high in March and July during breeding peaks. While most penguin group sizes were small (one or two birds), over 44 % of penguins occurred in groups of more than 10 birds. Three stereotypic penguin group formations occurred: 'facing-search', 'line-abreast', and 'pointed-ovoid'. Penguins also foraged in association with other sea birds and marine mammals.

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Boessenkool, Sanne, and n/a. "Spatial and temporal genetic structuring in yellow-eyed penguins." University of Otago. Department of Zoology, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090812.163749.

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Improving our understanding of the forces driving population decline and the processes that affect the dynamics of threatened populations is central to the success of conservation management. The application of genetic tools, including our ability to examine ancient DNA, has now revolutionised our ability to investigate these processes. The recent human settlement of the Pacific, particularly in New Zealand, provides a unique, accessible system for revealing anthropogenic impacts on native biota. In this thesis I use genetic analyses from modern, historic and subfossil DNA to investigate temporal and spatial genetic structuring of the endangered yellow-eyed penguin (Megadyptes antipodes), and use these analyses to answer questions related to the conservation of this species. The yellow-eyed penguin is endemic to the New Zealand region and currently breeds on the subantarctic Auckland and Campbell Islands and the southeast coast of the South Island. The current total population size is estimated around 6000-7000 individuals, of which more than 60% inhabit the subantarctic. Despite intensive conservation measures by governmental and local community agencies, population sizes have remained highly unstable with strong fluctuations in numbers on the South Island. The species was believed to be more widespread and abundant before human colonisation of New Zealand, thus current management assumed the mainland population to be a declining remnant of a larger prehistoric population. Genetic and morphological analyses of subfossil, historic and modern penguin samples revealed an unexpected pattern of penguin extinction and expansion. Only in the last few hundred years did M. antipodes expand its range from the subantarctic to the New Zealand mainland. This range expansion was apparently facilitated by the extinction of M. antipodes' previously unrecognised sister species, M. waitaha, following Polynesian settlement in New Zealand. The demise of M. waitaha is the only known human-mediated extinction of a penguin species. Despite M. antipodes' recent range expansion, genetic analyses of microsatellite markers reveal two genetically and geographically distinct assemblages: South Island versus subantarctic populations. We detected only two first generation migrants that had dispersed from the subantarctic to the South Island, suggesting a migration rate of less than 2%. Moreover, the South Island population has low genetic variability compared to the subantarctic population. Temporal genetic analyses of historic and modern penguin specimens further revealed that the harmonic mean effective population size of the M. antipodes South Island population is low (<200). These findings suggest that the South Island population was founded by only a small number of individuals, and that subsequent levels of gene flow have remained low. Finally, we present a novel approach to detect errors in historic museum specimen data in cases where a priori suspicion is absent. Museum specimens provide an invaluable resource for biological research, but the scientific value of specimens is compromised by the presence of errors in collection data. Using individual-based genetic analysis of contemporary and historic microsatellite data we detected eight yellow-eyed penguin specimens with what appear to be fraudulently labelled collection locations. This finding suggests errors in locality data may be more common than previously suspected, and serves as a warning to all who use archive specimens to invest time in the verification of specimen data. Overall, yellow-eyed penguins have a remarkable dynamic history of recent expansion, which has resulted in two demographically independent populations. These results reveal that anthropogenic impacts may be far more complex than previously appreciated.

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Green, Jonathan Andrew. "The behaviour and energetics of macaroni penguins (Eudyptes chrysolophus)." Thesis, University of Birmingham, 2001. http://etheses.bham.ac.uk//id/eprint/4758/.

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Heart rate (f\(_H\)) and rate of oxygen ( V\(_{O2}\) consumption were recorded from adult macaroni penguins while exercising on a treadmill. No differences were found in the relationship between f\(_H\) and V\(_{O2}\) in breeding and moulting female penguins, but a significant difference was found between male and female penguins. These relationships were used to estimate field metabolic rate (FMR) for free-ranging female penguins, which were implanted with heart rate and temperature data loggers. While foraging to provision their chick, FMR was 8.92 ± 0.44 W kg\(^{-1}\) and 9.07 ± 0.42 W kg\(^{-1}\) respectively while at-sea during the brood and crèche phases of the breeding season. While on-shore, the FMR was 6.08 ± 0.43 W kg\(^{-1}\) and 5.64 ± 0.40 W kg\(^{-1}\) respectively for the brood and crèche phases. During their moult fast, male and female penguins showed a pattern of increasing and then decreasing FMR and females had a mean FMR of 5.25 ± 0.88 W kg\(^{-1}\). The peak of energy expenditure was associated with maximum feather loss, probably due to increased costs of thermoregulation. During natural diving, penguins showed complex fluctuations in heart rate. Abdominal temperature fell during dive bouts with the magnitude of this decline increasing with bout length. Put together, these adjustments in heart rate and circulation may be enough to enable all natural dives to be aerobic in nature.

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18

Whittington, Phil 1958. "Survival and movements of African Penguins, especially after oiling." Doctoral thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/4366.

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Campbell, Kamahl. "An investigation of an infection with a protozoan parasite causing mortalities in Little Penguins (Eudyptula minor) on Penguin Island, Western Australia." Thesis, Campbell, Kamahl (2015) An investigation of an infection with a protozoan parasite causing mortalities in Little Penguins (Eudyptula minor) on Penguin Island, Western Australia. Masters by Research thesis, Murdoch University, 2015. https://researchrepository.murdoch.edu.au/id/eprint/28175/.

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Since at least 2001, routine post mortems of deceased penguins from Penguin Island, Western Australia, have been conducted at Murdoch University Veterinary Hospital (MUVH). In late 2011 and early 2012, a cluster of 12 cases presented with similar and characteristic gross and microscopic changes, namely birds in good body condition with hepatomegaly and splenomegaly, multifocal hepatic and splenic necrosis and numerous, small, 1-2μm diameter protozoan parasites within the necrotic foci. A review of earlier reports in the MUVH archive identified isolated similar cases from 2006 and 2008, which had been provisionally diagnosed as Avian Malaria, that is, Plasmodium spp. infection. An investigation was established in order to: a) definitively identify the parasite causing the mortalities, with the additional aims of: b) evaluating the live population of Penguin Island Little Penguins for the presence of parasitaemia, and c) investigating the possibility that another bird species present on Penguin Island might represent a reservoir of infection. Ninety-four blood smears were made from 79 individual Little Penguins collected from winter to summer of 2012 and in the early spring of 2013. One smear identified intraerythrocytic organisms consistent with the blood stages of an apicomplexan parasite, for example, merozoites or early gametocytes of Haemoproteus or Plasmodium, or merozoites or sporozoites of Babesia. Fifty-one blood smears were made from 51 Bridled Terns (Sterna anaethetus) captured during two visits to the island in November 2012 and March 2013, with no parasites detected in these smears. Electron microscopy of the protozoan parasite identified it as belonging to the phylum Apicomplexa. Further identification to the level of genus was not possible. Molecular identification of the parasite using Polymerase Chain Reaction (PCR) methodology gave inconsistent results. PCR performed by an independent laboratory identified a novel Haemoproteus spp. organism in 4 of 10 cases from this group; however, these results could not be replicated in our laboratory. Additional PCR using a variety of primers aimed at detecting members of the Apicomplexa identified a parasite from the family Sarcocystidae, which was subsequently identified as Toxoplasma. Immunohistochemistry of formalin fixed tissues also identified Toxoplasma in the hepatic and splenic lesions. The distinctive mortalities which were observed in this group of penguins, and which have occurred sporadically since, appear to be attributable to a fulminant toxoplasmosis, with or without a concurrent haemoproteosis in some cases. The significance of the apparent polyparasitism in some of the birds is unknown, as the relative contribution of concurrent Haemoproteus infection to the lesion aetiopathogenesis cannot be quantified at this time. Though the clinical signs of infection are unknown, the gross and microscopic appearance at post mortem is sufficiently characteristic to allow a diagnosis to be made on these features. Definitive confirmation of infection may be made by immunohistochemistry or PCR.

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Stone, Derik M. "Aggressive behavior of female and male magellanic penguins (spheniscus magellanicus) nesting at San Francisco Zoo, San Francisco, California." Scholarly Commons, 2000. https://scholarlycommons.pacific.edu/uop_etds/538.

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Between 15 March and 29 July 1998 we quantified aggressive movements (AMs) in a breeding colony of 44 adult magellanic penguins (MPs) during their nesting season at San Francisco Zoo (SFZ). We sampled their behavior for a total of 149.5 hrs in 46 sessions of 195 min each, all starting at 0945 hrs and stopping at 1300 hrs. We recognized 4 types of AMs, of which 2 (eye-pointing and charging) were threat signals, I (bill-fencing) was a ritualized contest of strength and agility, and I (biting) was physical attack. MPs only performed AMs within 2-3 m of nest entrances. Males performed 83% of all AMs, females 17%. The eye-pointing threat signal accounted for 92% of all AMs, and the 3 non-attack AMs combined accounted for 99% of all AMs; only I% involved physical assault. Both sexes performed eye-pointing and bill-fencing, but only males charged or bit their adversaries.

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21

Cassady, St Clair Colleen. "Mechanisms of brood reduction in Fiordland crested penguins (Eudyptes pachyrhynchus)." Thesis, University of Canterbury. Zoology, 1990. http://hdl.handle.net/10092/6953.

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Mechanisms of brood reduction were studied in Fiordland crested penguins (Eudyptes pachyrhynchus) on Open Bay Islands from July through October 1989. I quantified behavioural and environmental causes of egg and chick loss at the time of laying, during incubation, and after hatching to evaluate hypotheses advanced to explain the unique patterns of hatching asynchrony and egg dimorphism in eudyptid penguins. Although first eggs experienced lower survival than second eggs and most losses occurred during the laying interval, aggression between adult penguins did not appear to contribute to egg loss at any time. Similarly, egg mortality was not influenced by the effects of nest crowding or cover, or by the degree of intraclutch egg dimorphism. Egg temperatures were measured throughout the incubation period with thermocouples implanted in preserved eggs. Recorded temperatures increased markedly after the laying of the second natural egg, but did not differ between eggs of different sizes within a nest. First eggs were not consistently incubated in the anterior nest position and that position did not confer a thermal disadvantage. However, first eggs hatched later than second eggs. Retarded brood patch development may contribute to lower egg temperatures during the laying interval. Chicks from larger, second-laid eggs were larger at hatching, and grew more rapidly than their siblings. Overt aggression between feeding chicks was not observed and begging and feeding rates appeared to be similar. Nonetheless, large chicks experienced higher survival to the creche stage. Intra-clutch egg dimorphism was negatively correlated with the number of days two chicks survived in the same nest, but there was no relationship between survival and hatching asynchrony.

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22

Botes, Annelise. "Immunological and epidemiological investigations in South African ostriches and penguins." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53747.

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Dissertation (PhD)--University of Stellenbosch, 2004
ENGLISH ABSTRACT: Newcastle disease (NO) and mycoplasma infections in ostriches have considerable economic implications for the South African ostrich industry in that NO is a limiting factor in the export of ostrich products to the European Union and mycoplasma infections cause stock losses, reduced production, reduced hatchability and downgrading of carcasses. In the first section of this dissertation, the role of passively acquired and mucosal immunity in protection of ostrich chicks against Newcastle disease virus (NOV) was investigated. Ostrich hen serum IgG and yolk IgY were isolated and characterized, and the transfer of maternal anti-NOV antibodies to the egg yolk was determined using an enzyme-linked immunosorbent assay (ELISA). Results indicated that anti-NOV antibodies were successfully transferred from the ostrich hen to the egg yolk. In addition, ostrich IgA was isolated, characterized and rabbit anti-ostrich IgA antibodies produced and used for measuring mucosal anti- NOV IgA antibodies produced in response to mucosal vaccination. Results indicated that the live La Sota vaccine stimulates IgA production and thus mucosal immunity in ostrich chicks. In the second section of this dissertation, ostrich mycoplasmas were isolated and identified using 16S rRNA gene sequencing. These sequences indicated that ostriches carry three unique mycoplasmas, which are phylogenetically quite divergent. The 16S rRNA gene sequences of the ostrich mycoplasmas were subsequently used for the development of specific primers for the detection and diagnosis of mycoplasma infections in ostriches by PCR. The last section of this dissertation focuses on avian malaria in African penguins and the management of this disease during rehabilitation. The Foundation for the Conservation of Coastal Birds (SANCCOB) is a seabird rescue and rehabilitation centre, which is largely dedicated to the rehabilitation of diseased, injured and oiled penguins. Significant mortalities due to avian malaria occur at this facility. The aim of this study was the development of an ELISA for the purpose of assessing the natural levels of anti-Plasmodium antibodies in African penguins on entry into the SANCCOB facility and during rehabilitation. Results indicated significant increases in anti- Plasmodium antibody levels after entry, which was not influenced by oiling. Infection with malaria and not parasite recrudescence was viewed to be the cause of this increase, indicating a possible role of the SANCCOB facility in exposing penguins to avian malaria.
AFRIKAANSE OPSOMMING: Newcastlesiekte (NS) en mikoplasmainfeksies in voltruise het geweldige ekonomiese implikasies vir die Suid-Afrikaanse volstruisbedryf. Die rede hiervoor is dat NS 'n beperkende faktor in die uitvoer van volstruisprodukte na die Europese Unie is, en mikoplasmainfeksies tot kudde verliese, verlaagde produksie en uitbroei asook lae gradering van karkasse lei. In die eerste gedeelte van hierdie proefskrif is die rol van passiewe- en mukosale-immuniteit in die beskerming van volstruiskuikens teen NS virus (NSV) ondersoek. Volstruishenserum IgG en eier IgY is geïsoleer en gekarakteriseer en die oordrag van maternale anti-NSV antiliggame na die eier ondersoek met behulp van 'n 'enzyme-linked immunosorbent assay' (ELISA). Resultate het getoon dat anti-NSV antiliggame suksesvol van die hen na die eier oorgedra is. Volstruis IgA is ook geïsoleer, gekarateriseer en konyn anti-volstruis IgA antiliggame geproduseer wat gebruik is vir die bepaling van mukosale anti-NSV IgA antiliggame in reaksie op mukosale immunisering. Resultate het getoon dat lewendige La Sota entstof IgA produksie stimuleer en dus tot mukosale-immuniteit in volstruiskuikens lei. In die tweede gedeelte van hierdie proefskrif is volstruismikoplasmas geïsoleer en geïdentifiseer met behulp van 16S rRNA geenopeenvolgingsbepalings. Hierdie volgordes het getoon dat drie unieke mikoplasmas in volstruise voorkom wat filogeneties verskillend blyk te wees. Die 16S rRNA geenopeenvolgings van die volstruismikoplasmas is gebruik vir die ontwikkeling van spesifieke inleiers vir die PKR identifisering en diagnose van mikoplasmainfeksies in volstruise. Die laaste gedeelte van hierdie proefskrif fokus op voëlmalaria in die Afrika pikkewyn en die bestuur van hierdie siekte gedurende rehabilitasie. Die 'South African Foundation for the Conservation of Coastal Birds' (SANCCOB) is 'n seevoëlreddingsen rehabilitasie-sentrum vir siek, beseerde en ge-oliede pikkewyne. Hierdie sentrum het egter aansienlike vrektes as gevolg van voëlmalaria. In hierdie studie is 'n ELISA ontwikkel vir die bepaling van natuurlike anti-Plasmodium antiliggaamvlakke van pikkewyne by aankoms en tydens rehabilitasie by SANCCOB. Resultate het 'n toename in anti-Plasmodium antiliggaamvlakke getoon na toelating wat nie beïnvloed is deur olie nie. Hierdie toename kan toegeskryf word aan nuwe malariainfeksies en nie 'n heruitbraak van bestaande infeksies nie wat daarop dui dat pikkewyne aan voëlmalaria blootgestel word by die SANCCOB-sentrum.

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Cresswell, Katherine A. "Behavioural models of penguins and krill in the Southern Ocean." Thesis, Open University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427734.

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Pütz, Klemens. "Untersuchungen zur Ernährungsökologie von Kaiserpinguinen (Aptenodytes forsteri) und Königspinguinen (Aptenodytes patagonicus) = Aspects of the feeding ecology of Emperor Penguins (Aptenodytes forsteri) and King Penguins (Aptenodytes patagonicus) /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1994. http://www.gbv.de/dms/bs/toc/153239980.pdf.

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25

Handley, Jonathan Murray. "Foraging ecology of gentoo penguins pygoscelis papua at the Falkland Islands." Thesis, Nelson Mandela University, 2017. http://hdl.handle.net/10948/14113.

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Marine top predators often occupy broad geographical ranges that encompass varied habitats. Therefore, a pre-requisite towards conserving these animals is to determine the components of their realized niche, and investigate whether a species is a specialist or a generalist. For generalist species, it is also necessary to understand if local specialisation occurs. Uncovering these components can allow us to build models of a species realized niche that may then be used to infer habitat use in unsampled locations. However, fully understanding the components of a marine top predators realized niche is challenging owing to the limited opportunity for in situ observations. Overcoming these limitations is a key step in marine top predator research. It will enhance our understanding of trophic coupling in marine systems, and aid in the development of tools to better study these predators in their dynamic environment. Seabirds, penguins (Spheniscids) in particular, are a group of animals for which investigating their realized niche is of vital importance. This is because numerous species face growing uncertainty in the Anthropocene, and in a time of rapid environmental change there is furthermore a need to better understand the potential use of these birds as indicators of ecosystem health. The aim of this thesis, therefore, is to investigate the foraging ecology of gentoo penguins (Pygoscelis papua) at the Falkland Islands. At the Falkland Islands, limited historical information exists regarding this species foraging ecology, with most information coming from a single location at the Falklands. As the Falkland Islands have the world’s largest population of gentoo penguins, elucidating factors influencing this population will have global relevance. Furthermore, historical information indicated potential competition with fisheries, and with prospecting for hydrocarbons and an inshore fishery, there is a need to understand the distribution of these birds across the islands. Penguins are also well suited to carry biologging devices allowing for in situ observations of inter and intraspecific interactions, as well as habitat specific interactions. In this study, I sampled birds over three breeding seasons, from four breeding colonies - chosen for their varied surrounding at sea habitat - across the Falkland Islands. I investigated the diet with stomach content and stable isotope analysis, the at-sea distribution with GPS and time depth recorders, and how these birds behaved at sea using custom made animal-borne camera loggers. Furthermore, I developed a method to recognise prey encounter events from back mounted accelerometers, using a supervised machine learning approach. As part of the first species specific description of diet at this scale for the Falklands, I revealed six key prey items for the birds: rock cod (Patagonotothen spp.), lobster krill (Munida spp.), Falkland herring (Sprattus fuegensis), Patagonian squid (Doryteuthis gahi), juvenile fish (likely all nototheniids), and southern blue whiting (Micromesistius australis). The use of animal-borne camera loggers verified that not only do gentoo penguins consume a diverse array of prey items, but they adopted various methods to capture and pursue prey, with evidence of birds following optimal foraging theory. Prey composition varied significantly between study sites with the at-sea distribution and habitat use of penguins reflecting that of local prey. Birds from colonies close to gently sloping, shallow waters, foraged primarily in a benthic manner and had larger niche widths. However, those at a colony surrounded by steeply sloping, deeper waters, typically foraged in a pelagic manner. Contrasting diet patterns were also prevalent from stable isotope data, and the niche widths of birds relating to both stomach content and stable isotope data were larger at colonies where benthic foraging was prevalent. Therefore, it was clear that surrounding bathymetry played a key role in shaping this species’ foraging ecology, and that at the population level at the Falkland Islands birds are generalists. However, at individual colonies some specialisation occurs to take advantage of locally available prey. I developed habitat distribution models - via boosted regression trees – which transferred well in time but poorly across space. Reasons for poor model transfer might relate to the generalist foraging nature of these birds and the reduced availability of environmental predictors owing to the limited range of these birds. I furthermore developed a method to identify prey encounter events that can also, to a degree, distinguish between prey items. This method will be a promising approach to refine habitat distribution models in future. These habitat distribution models could potentially contribute to marine spatial planning at the Falkland Islands. Footage from animal-borne camera loggers clearly showed that prey behaviour can significantly influence trophic coupling in marine systems and should be accounted for in studies using marine top predators as samplers of mid to lower trophic level species. Ultimately, flexibility in foraging strategies and inter-colony variation will play a critical role when assessing factors such as interspecific competition or overlap with anthropogenic activities.

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Waas, Joseph Rupert. "Agonistic and sexual communication in the little blue penguins, Eudyptula minor." Thesis, University of Canterbury. Zoology, 1988. http://hdl.handle.net/10092/5827.

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The little blue penguin, Eudyptua minor, was used to examine three specific issues in animal communication. (1) Ethologists have traditionally viewed social repertoires as being fixed and invariable. In contrast, my analysis of agonistic behaviour of little blue penguins occupying two different habitats revealed significant variation in repertoire size and form. Cave-dwellers, which had large and complex repertoires, occupied open colonies characterized by high interaction rates. Burrow-dwellers, which had small repertoires, occupied colonies in which conspecifics were isolated from one another and rarely interacted. Despite higher interaction rates, cave-dwellers attacked one another less often and used overtly aggressive behaviours with shorter durations than did burrow-dwellers. The results suggest that the size and form of repertoires may be mediated by the social and physical properties of occupied habitats. Large repertoires may reduce the proportion of encounters leading to overt aggression where interaction rates are high. (2) Theoretical models of aggressive communication suggest that animals are unlikely to use aggressive displays to signal motivation. Using lag sequential analysis, I examined over 2000 agonistic interactions between cave-dwelling penguins. The results suggested that aggressive displays differ in how costly they are to perform (i.e. as measured by the risk of escalation) and that high cost displays were more effective in deterring opponents than low cost displays. I argue that animals can signal motivation by taking risks during interactions, as demonstrated by their choice of display. (3) The social facilitation of courtship behaviour is a widely assumed but rarely demonstrated process thought to be related to breeding synchrony. Using a playback experiment, I demonstrated that the acoustic components of penguin displays facilitated courtship behaviour from perceiving conspecifics. I argue that social facilitation may alter the availability of social stimuli and cluster acts of copulation, both of which may influence the timing and synchrony of breeding.

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Naude, Vincent Norman. "Prevalence and drivers of blood parasitism in African penguins (Spheniscus demersus)." Bachelor's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/12924.

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Includes bibliographical references.
In the past decade African penguin (Spheniscus demersus) populations have experienced declining population sizes of > 60% in some instances. This has primarily been attributed to shifting prey availability and competition with regional purse-seine fisheries; however, possible novel threats exacerbated by diminishing population sizes and increased stress, may also be important contributors to the regional persistence of the species. These threats include the impacts of arthropod-borne blood parasites on the health of penguin populations. While parasitism of wild penguins has been poorly studied, susceptibility to infection with blood protozoa is well established in a wide range of penguin species held in captivity. This thesis assesses the prevalence of blood parasites in wild African penguins throughout the greater Agulhas-Benguela ecosystem. Using PCR-based techniques, 317 individuals were screened for the presence of known haemoparasite species of Plasmodium, Haemoproteus and Babesia across 12 breeding colonies. Babesia infection was confirmed for 60% of wild birds sampled, but methods used did not indicate infection with either Haemoproteus or Plasmodium species. Generalised linear modelling of ecological and life history parameters suggests that Babesia prevalence is primarily driven by a colony’s distance from the mainland, decreasing significantly as distance from the mainland increases. Captive birds held at the SANCOBB rehabilitation facility in Cape Town present with both Plasmodium and Babesia species, providing the positive controls for the study. The relative scarcity of Plasmodium and Haemoproteus infection in the wild may be the result of an absence of suitable vectors and/or high post mortality in the host. Alternatively, the sensitivity of the method used requires further investigation as Plasmodium infection has been confirmed previously in penguin populations using PCR-based approaches. This study provides the first baseline estimate of blood parasitism in African penguins across their breeding range, and raises the need for further research and monitoring. The results suggest that high Babesia prevalence in African penguins may be related to (1) an ecological system of chronicexposure to infection reservoirs, such as the co-occurring cormorant and gannet populations and (2) increasing anthropogenic impacts, especially in mainland colonies. Data on blood parasitism in co-occurring seabird species is required to fully elucidate their role in Babesia infection dynamics in the region. To improve understanding and facilitate timely detection of changes in blood parasite exposure, standardised methodologies are advocated to better inform the conservation management of this iconic species.

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Thiart, Hanlie. "Immunological and epidemiological investigations into avian malaria in the African penguin during rehabilitation and in breeding colonies." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/16620.

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Thesis (MSc)--University of Stellenbosch, 2005.
ENGLISH ABSTRACT: The African penguin, which occurs along the south-eastern and south-western shores of South-Africa and Namibia, has experienced a severe reduction in population numbers due to guano and egg collection in the first half of the 19th century, and oil pollution in the second half of the 19th century as a result of oil tankers rounding the Cape of Good Hope. The population would have been reduced by a further 19% had it not been for the rehabilitation of penguins at the South African National Council for the Conservation of Coastal Birds (SANCCOB) facility. Although this has been very successful, mortalities as a result of avian malaria infection have considerably reduced the efficiency of rehabilitation. In an effort to assess the role of immunity against malaria in combating the disease, an enzyme-linked immunosorbent assay (ELISA) for the detection of antibody levels to avian malaria was developed. The ELISA was used to detect antibody levels to avian malaria of penguins on entry and during rehabilitation from October 2001 to January 2003. The aim of this study was to continue the determination of antibody levels to avian malaria of penguins entering the SANCCOB facility, in order to allow an evaluation of the antibody levels to avian malaria for two full calendar years. This investigation was combined with a polymerase chain reaction (PCR)-based method, capable of detecting any Plasmodium species in penguin serum. These two methods were also used to investigate avian malaria in several breeding colonies in order to assess the role avian malaria may play in the survival of the African penguin in the wild. Results indicated that the ability of penguins to produce anti-Plasmodium antibodies was not influenced by oiling and that infection with malaria was not due to recrudescence but rather due to infection via mosquitoes. This indicated a possible role of the SANCCOB facility in exposing the penguins to avian malaria. However a large number of penguins arrived at the facility previously infected with malaria, indicating that malaria was present in the breeding colonies. Investigations in the breeding colonies revealed extremely high avian malaria prevalence even though no sick birds or mortalities were observed. This raised the question whether different types of malaria are responsible for infection in the SANCCOB facility and breeding colonies.
AFRIKAANSE OPSOMMING: Die Afrika Pikkewyn kom langs die suid-oostelike en suid-westelike kus van Suid Afrika en Namibië voor. In die afgelope eeu het hierdie spesie ‘n geweldige afname in populasie getalle ondervind. Dit was hoofsaaklik die gevolg van die versameling van guano en pikkewyneiers in die eerste helfte van die 19de eeu en oliebesoedeling in die tweede helfde van die 19de eeu. Die “South African Foundation for Conservation of Coastal Birds” (SANCCOB) is ‘n seevoëlreddings- en rehabilitasiesentrum vir siek, beseerde en ge-oliede pikkewyne. Dit word geskat dat die Afrika Pikkewyn populasie met ‘n verdere 19% sou afgeneem het as dit nie vir die rehabilitasie by die SANCCOB sentrum was nie. Hierdie sentrum het egter aansienlike vrektes in die somer as gevolg van voëlmalaria, wat sodoende die effektiwiteit van die rehabilitasie verlaag. In ‘n poging om die rol van immuniteit teen malaria te bepaal is ‘n “enzyme-linked immunosorbent assay” (ELISA) ontwikkel vir die bepaling van antiliggaam vlakke teen malaria. Hierdie ELISA is gebruik vir die bepaling van die anti-Plasmodium antiliggaam vlakke van die pikkewyne by aankoms en ten tye van rehabilitasie by SANCCOB vanaf Oktober 2001 to Januarie 2003. Die doel van hierdie studie was eerstens om hierdie ELISA bepalings voort te sit om sodoende antiliggaam vlakke teen malaria oor twee kalender jare te kan evalueer. Hierdie ondersoek was gekombineer met ‘n polimerase ketting reaksie (PCR) metode, wat enige Plasmodium spesie in pikkewynserum sou kon opspoor. Hierdie twee metodes is ook gebruik vir ondersoeke in sommige broeikolonies, met die doel om te bepaal watter rol voëlmalaria in die oorlewing van die Afrika pikkewyn in die natuur speel. Resultate het getoon dat olie nie die vermoë van die pikkewyn beïnvloed om anti- Plasmodium antiliggame te vervaardig nie en dat malaria infeksie hoofsaaklik deur muskiete veroosaak word en nie deur heruitbraak van ‘n bestaande infeksie nie. Dit dui egter daarop dat pikkewyne blootgestel word aan voëlmalaria by die SANCCOB sentrum. Daar is ook gevind dat ‘n groot aantal pikkewyne met malaria infeksies by die sentrum opgedaag het wat dui op die voorkoms van malaria in die broeikolonies. Ondersoeke in die broeikolonies het ‘n besonder hoë voorkoms van malaria onthul. Geen vrektes of siek pikkewyne is in die broeikolonies waargeneem nie, wat moontlik kan beteken dat pikkewyne by SANCCOB met ‘n ander tipe malaria geïnfekteer word as in die broeikolonies.

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29

Mårtensson, Anders. "Flying Penguins : Building and Evaluating the Viability of a Linux-based Drone." Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12860.

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Traditional quadcopter flight controllers use microcontrollers to run the code that keeps the drone in the air, and when more processing power or versatility is needed the same microcontrollers are used in tandem with Linux-based single-board computers. It would be cheaper and reduce complexity if the single-board computer could entirely replace the microcontrollers. We investigate whether it is possible to run a quadcopter using a Linux single-board computer as the flight controller, with no microcontrollers and otherwise the same hardware as used in hobby-grade quadcopters. We attempt to find out what the potential issues are and how to get around or mitigate them. To test it, a quadcopter will be built from hobby parts and the flight control software to be run on the flight controller will be developed. More specifically, the pulse-width modulation signals to the motor speed controllers are checked for stability and various methods of acquiring the radio control input in the form of pulse-width modulation signals are evaluated. The speed at which the flight control software is running is measured under different circumstances—with and without load and with and without mitigative measures active. We conclude that it was not possible to run a quadcopter using only the chosen Linux SBC as flight controller. The reason was because we could not accurately measure the radio control input, although there may be other additional issues. We did find that CPU time did not seem to be an issue even when an artificial stress was placed on the system, despite not being a real time system, and even less of an issue when the mitigation techniques discussed were applied.

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30

Taylor, Sabrina Simone. "Parental care during incubation and chick-rearing in Humboldt penguins, Spheniscus humboldti." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0034/MQ66588.pdf.

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31

Grilo, Miguel Luca Augusto. "Characterization of infection by malaria parasites in penguins housed in zoological collections." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/7505.

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Dissertação de Mestrado Integrado em Medicina Veterinária
Avian malaria is, if not the main, one of the most important causes of mortality in penguins housed in zoological collections. Knowledge of prevalence in zoos and the control measures applied (diagnostic, treatment and prophylaxis) allows other zoos to increase their colonies protection. In order to evaluate malaria infection in penguin colonies and zoos prophylactic programs, a survey was specifically designed to gather this information from different zoological gardens from Europe, North America and Asia. Fifteen out of the forty zoos that answered (37,5%) test their colonies for malaria, revealing a global prevalence of 12,5% (5 zoos) of institutions with infected penguins. Diagnostic techniques most currently used are optical microscopy (11), histopathology (10) and observation of clinical signs (9). Twelve zoos use combinated techniques diagnosis protocols. Mixed infections with other blood parasites were reported by one zoo. Significant differences were not presented in clinical and laboratorial signs presented, being lethargy (4) the most prevalent sign. Nine zoos (22,5%) use treatment protocols on detected cases. No significant differences were observed in the protocols being the standard ones for most institutions based on sulfadiazine and pyrimethamine, chloroquine and primaquine. Twenty two zoos (55%) use prophylaxis protocols, being primaquine the most common drug in eight zoos. Seventeen zoos (42,5%) reported that no preventive measures besides preventive therapeutic protocols are used, while reducing the number of potential water catchment containers in order to eliminate the mosquito breeding sites available, was the measure most commonly adopted in 13 zoos (32,5%). To the author’s knowledge, these are the first reports on penguins of anorexia and vomit when using sulfadiazine and pyrimethamine; anorexia when using primaquine and chloroquine and epileptic seizures, sunburns around the eyes and death when using pyrimethamine. This study shows that many zoological gardens do not have routine control programs for malaria in their penguin colonies. Dissemination of these results allows for a better understanding of this problem, raising awareness and potentially inducing new perspectives on its control.
RESUMO - A malaria aviária é, se não a principal, uma das causas mais importantes de mortalidade em pinguins alojados em coleções zoológicas. O conhecimento da prevalência em zoológicos e das medidas de controlo aplicadas (diagnóstico, tratamento e profilaxia) permite a outros zoológicos melhorar a proteção das suas colónias. Com o objetivo de avaliar a infeção por agentes de malária em colónias de pinguins e os programas profiláticos dos zoológicos, foi criado um questionário para reunir esta informação em diferentes jardins zoológicos da Europa, América do Norte e Ásia. Quinze dos quarenta zoológicos que responderam (37,5%) testam as suas colónias relativamente a malária, revelando uma prevalência global de 12,5% (5 zoológicos) de instituições com pinguins infetados. As técnicas de diagnóstico mais frequentemente utilizadas são a microscopia ótica (11 zoos), a histopatologia (10) e a observação de sinais clínicos (9). Doze zoológicos utilizam protocolos de diagnóstico com diferentes técnicas. Infeções mistas com outros parasitas sanguíneos foram referidas por um zoo. Não foram apresentadas diferenças significativas nos sinais clínicos e laboratoriais apresentados, sendo a letargia o mais frequente (4). Nove zoológicos (22,5%) usam protocolos de tratamento em casos detetados. Não foram observadas diferenças significativas nos protocolos utilizados, sendo os padrões para a maioria das instituições baseados em sulfadiazina e pirimetamina, cloroquina e primaquina. Vinte e dois zoológicos (55%) usam protocolos de profilaxia, sendo a primaquina a substância mais comum em oito zoológicos. Dezassete zoológicos responderam que não utilizam medidas preventivas para além dos protocolos terapêuticos preventivos, enquanto que a redução do número de potenciais recipientes de captação de água, de modo a eliminar os locais de reprodução disponíveis para os mosquitos, foi a mais comummente adotada em 13 zoológicos (32,5%). No conhecimento do autor, estas são as primeiras descrições em pinguins de anorexia e vómito ao administrar sulfadiazina e pirimetamina; de anorexia ao administrar primaquina e cloroquina e de ataques epiléticos, reacções de fotosensibilidade e morte ao administrar pirimetamina. Este estudo demonstra que muitos jardins zoológicos não têm programas rotineiros de controlo da malária relativamente às suas colónias de pinguins. A divulgação destes resultados permite uma melhor compreensão deste problema, criando sensibilização e, potencialmente, conduzindo a novas perspetivas no seu controlo.

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32

Hart, Tom. "Aspects of the ecology of macaroni penguins (Eudyptes chrysolophus) around South Georgia." Thesis, Imperial College London, 2009. http://hdl.handle.net/10044/1/5667.

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Macaroni penguins (Eudyptes chrysolophus Brandt) feed when diving during long foraging trips away from their breeding colony. Their foraging behaviour is constrained by a number of factors including their physiology, their condition, the condition of their partner, and the condition of their chick. This thesis concerns aspects of their foraging ecology in relation to prey availability. Time Depth Recorders and other archival tags are increasing in their capacity, battery life and durability at the same time as getting cheaper and smaller and are frequently used to explore foraging behaviour. However, development and application of techniques to analyse these resulting data sets lags behind our ability to collect the data. This thesis develops new methods and uses data from 129 macaroni penguins collected over 6 years to determine patterns of foraging behaviour. In particular: 1. Appropriate identification of sex is essential to any study of foraging ecology, in particular during the breeding season. In response to an identified problem with morphometric sexing, I conduct a validation test between molecular and morphometric sex tests and make conclusions about the nature and identity of error in these tests. 2. I use summary statistics to characterise dives. This work suggests that time series techniques may provide insights that have been lacking from previous analyses. I apply time series techniques to the data to model non-independence in data sets and to compare results obtained using auto-correlation methods with findings obtained from (1) above. The time series approach allows a comparison of different temporal elements of dives, in particular correlations between features of successive dives and how correlation between dives decays with time. 3. I use Hidden Markov Models as a clustering algorithm to provide a statistically robust description of patterns in dives that may outperform the widely used concept of bouts of dives. I then use this method to determine whether such clustering of dives exists in my data. Characteristics of bouts and types of dives vary with year, the stage and sex of the individual. 4. Hidden Markov Models do not provide a direct replacement for the concept of bouts. Rather than identify bouts as summary statistics of diving activity, I take daily summaries of activity. I then use these to overcome the nonindependence of dives and to determine the relative periods of dive activity and travel or searching. Comparison between the adult and chick fledging weights revealed a strategy of investment in the chick at the expense of the adult body mass. The application of time series techniques has led to new insights about the timing of decision-making, but this thesis reveals that further advances also require positional data to be combined with temporal activity data.

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33

Whitehead, Thomas Otto. "Comparative foraging ecology of macaroni and rockhopper penguins at the Prince Edward Islands." Doctoral thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/27338.

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Penguins are one of the largest consumers of marine resources in the Southern Ocean and spend most of their lives at sea. Although the last four decades have seen technological advancements that have considerably expanded our knowledge about their at-sea behaviour, there is still much to be learned. Given the rapid ongoing ecosystem changes in the Southern Ocean, it is vital to better understand, firstly, how penguins respond to environmental variability, and secondly, how such changes alter ecological relationships between sympatric species. Being flightless, travel is slower and more costly for penguins than flying seabirds. This constrains their ability to find resources, particularly during the breeding season when they must regularly return to the colony to provision offspring. As penguins are colonial nesters, high foraging pressure near the colony can limit available resources, enhancing potential intra- and interspecific competition. At many localities, ecologically similar penguin species breed sympatrically. In such cases, co-existence is only thought possible through ecological segregation in space, time and/or diet. At the Prince Edward Islands, approximately 302,000 pairs of macaroni Eudyptes chrysolophus and 80,000 pairs eastern rockhopper E. chrysocome filholi penguins breed sympatrically. These populations are closer to parity than at any other locations where two eudyptid species breed sympatrically. Populations of both species at the Prince Edward Islands have declined in the last two decades, but drivers of these declines are poorly understood. The primary aim of this thesis was to better understand the foraging strategies of macaroni and rockhopper penguins at the islands and identify aspects of their ecology that allow them to co-exist. The secondary focus was to investigate how each species responds to environmental variability and assess how ecological interactions between species might be altered in an era of rapid global change. To study the at-sea habitat use and diving behaviour of penguins during chick-rearing and pre-moult periods, I used GPS loggers and time-depth recorders. To track penguins during the winter I used geolocation loggers and satellite transmitters. Stable isotope analyses were used to investigate trophic ecology during late winter, summer and pre-moult periods. During the breeding season, both species primarily foraged in pelagic waters beyond the shelf break (> 3000 m), with macaroni penguins foraging slightly farther offshore on average. However, rockhopper penguins breeding adjacent to the inter-island shelf foraged in shallow waters (< 200 m) over the shelf. Both species dived to similar depths (40 to 60 m), but macaroni penguins dived deeper more often. The diet of both species was dominated by two krill species (Thysanoessa vicina and Euphausia vallentini). Diving behaviour varied between years, with both species diving deeper when the SAF was located farther away and geostrophic flow was reduced. During these conditions, macaroni penguins fed on a larger proportion of myctophids whereas rockhopper penguins resorted to less energy-dense nototheniids. This highlights contrasting responses to periods of low krill availability. During the pre-moult period, habitat preferences were similar between species, with penguins travelling up to 1000 km south to forage in Antarctic Zone waters (SST 3-4 °C). However, a three-week difference in departure dates minimised spatiotemporal overlap between species. Diving behaviour was similar between species, but macaroni penguins performed more deep dives and encountered thermoclines more often. Stable isotope analyses revealed that macaroni penguins fed on a greater proportion of fish than rockhopper penguins, and revealed species-specific spatial responses to changes in primary productivity, with macaroni penguins travelling farther south in less productive years. During the 6-month long winter sojourn, macaroni penguins generally foraged in cooler waters (SST ~ 3 °C) compared to rockhopper penguins (5-6 °C). However, stable isotope analyses revealed that trophic and spatial overlap were high during late winter. Both species associated with mesoscale eddies and submesoscale filaments, suggesting that these features play an important role in aggregating prey during the resource-limited winter months. In summary, it appears that subtle differences exist to minimise competitive overlap between macaroni and rockhopper penguins. The three-week difference in the onset of breeding is integral to minimising competitive overlap during late winter, brood-guard/crèche, pre-moult and immediately following the moult. This allochrony staggers the peak energy demands of rockhopper penguins to reduce overlap with macaroni penguins. The larger-bodied macaroni penguins are capable of diving deeper, for longer and more efficiently than rockhopper penguins, which increases their behavioural flexibility and fitness by minimising stresses associated with reduced krill availability. Such differences in diving behaviour may explain contrasting population trends at the islands and suggests that rockhopper penguins may continue to decline at a faster rate than macaroni penguins if ongoing climate change continues to reduce prey availability around the Prince Edward Islands.

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Tol, Leanne. "Factors impacting the breeding success of African penguins Spheniscus demersus on Robben Island." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20873.

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The African penguin Spheniscus demersus is a seabird endemic to the south-western coast of Africa and can be found in three main breeding localities; southern Namibia, the Western Cape and Algoa Bay, Eastern Cape, South Africa. The African penguin has been listed as Endangered since 2010, having experienced a decline in population of more than 50% over the past three generations. This study was conducted at the breeding colony on Robben Island, South Africa, and examined two factors that have the potential to affect breeding success of African penguins; body mass at the onset of breeding and the suitability of various nest types to mitigate changing climatic conditions. Body mass was measured by recording weights using an automated weighing scale set up in front of a nest. Weights were taken at the start of breeding of each penguin in a breeding pair and these weights were compared to the number of chicks fledged, fledging period, hatching success, clutch size, and chick fledging weight. Hatching success, clutch size, and fledging weight were not influenced by the mass of either parent. There was a trend of shorter fledging periods as the mass of the heavier parent increased. The greatest effect was from the body mass of the lighter parent on the number of chicks that fledged from the nest; as the mass of the lightest adult increased, more chicks were fledged. If the lighter adult weighed below 2 kg there were always no chicks at the nest that fledged. This suggests evidence for a carry-over effect of body mass from the time before breeding starts into the breeding season, and highlights the importance of food availability for African penguins on a global scale, and not just a local one. The proportion of nest failures of six nest types (vegetation, open, natural burrow, building, wooden nest box, and artificial fibreglass burrow) at the incubation and chick-rearing stage were compared to rainfall and maximum temperature.

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Hampton, Shannon. "A preliminary investigation into effects of flipper banding on African penguins spheniscus demersus." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/6265.

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Includes abstract.
Includes bibliographical references.
Much of what is known about penguin movements and life history traits, including their population dynamics, and particularly the rehabilitation success after oil spills results from information derived from marking birds with flipper bands. However, flipper bands may negatively impact the welfare of penguins. While studies on the impact of banding have been undertaken for several penguin species, no such study has investigated the exclusive effect of banding on African Penguins Spheniscus demersus. I do so by comparing the difference in yearly return rates as well as foraging trip durations of 100 individuals injected with a subcutaneous transponder only, and 100 that have both transponders and a stainless steel flipper band.

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Olsson, Evelina, and Ida Stjerna. "“They’re not that different from us, really” : En analys om hur kejsarpingviner representeras i två naturfilmer." Thesis, Högskolan Dalarna, Bildproduktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:du-31632.

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Syftet med uppsatsen är att undersöka och analysera hur kejsarpingviner representeras i naturfilmerna March of the Penguins (2005) och Snow Chick: A Penguin's Tale (2015). Uppsatsen fokuserar främst på hur föreställningar om genus och mänskliga normer om familjestrukturer syns i filmerna samt hur kejsarpingvinernas relation och beteenden till varandra representeras. Vi använder genus som den teoretiska utgångspunkten i uppsatsen. De filmer som analyseras är March of the Penguins och Snow Chick: A Penguin’s Tale. Vi analyserar filmerna utifrån Roland Barthes semiotiska teori genom begreppen denotation och konnotation. Resultatet av analysen visar att de två filmerna representerar pingvinerna på liknande sätt, genom att tillskriva förmänskligande egenskaper och beteenden på djuren utifrån föreställningar om genus och mänskliga normer om familjestrukturer. Resultat av analysen visar främst att filmerna endast skildrar det heterosexuella förhållandet och den traditionella kärnfamiljen.

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Handley, Jonathan Murray. "Diet and foraging distribution of gentoo penguins pygoscelis papua at Cow Bay, Falkland Islands." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020377.

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Knowledge of diet and distribution in marine top predators is critical in interpreting their ecological role. Furthermore, this information is required for effective management and conservation of these species. For gentoo penguins at the Falkland Islands a previous overlap in dietary items with commercial fisheries was recognised. Despite this the at-sea distribution has been poorly studied and only at a few localities. Therefore, this thesis looks to broaden the knowledge of foraging ecology for gentoo penguins at another site in the archipelago, Cow Bay. The aim was firstly, through stomach content analysis, to determine if diet changed over a large temporal scale (2002/03/04 – 2011/12/13), and between the chick guard and crèche periods of chick rearing. Secondly, through GPS loggers, to assess distribution at sea during the incubation and chick guard periods (2012/13). Additionally, foraging ecology between genders was investigated. Gentoo penguins at Cow Bay foraged primarily on fish (66-99 percent) throughout the entire study period. The principle prey item by mass was Patagonotothen spp., considered previously as discard by fisheries but now an important commercial resource, for all periods (47-78 percent) except that of the 2012/13 crèche period (19 percent). During this period Sprattus fugensis made up the bulk of the diet (52 percent). Cephalopods, particularly Loligo gahi (1-24 percent), were also prominent in the diet and crustaceans contributed negligibly. The diet indicated that gentoo penguins are capable of both a benthic and pelagic feeding strategy which likely reflects changes in local prey abundance. Birds typically conducted foraging activities during daylight hours with greater trip duration, path length, maximum distance and area utilised during the incubation period than the guard. All trips were confined to the continental shelf and within the boundaries of a marine management zone, the Falkland Islands Interim Conservation Zone (FICZ). Males and females fed on the same size and composition of prey items. Trip duration, path length and maximum distance from the colony were not significantly different, although males foraged in a slightly larger area than females marginally to the north. As at-sea distribution was confined within the FICZ this management area provides protection to food resources of gentoo penguins breeding at Cow Bay. At this site, the population is increasing, likely associated with increased prey availability as evidenced by record catches of Patagonotothen spp. in recent years at the Falkland Islands. Continued long term monitoring of gentoo penguin diet and fishery yields to allow detection of possible competition in the future is recommended. As marine sentinels, on-going monitoring of gentoo penguin populations at the Falkland Islands is likely to provide early warning signs of reduced prey availability.

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Huyser, Onno Adrian Wallace. "Diet and foraging behaviour of Macaroni and Chinstrap penguins at Bouvetøya, South Atlantic Ocean." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/4751.

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Thier, Katrin. "Of picts and penguins – Celtic Languages in the New Edition of the Oxford English Dictionary." Universität Potsdam, 2007. http://opus.kobv.de/ubp/volltexte/2008/1932/.

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Extract: [...]The New English Dictionary, later to become the Oxford English Dictionary, was first published between 1884 and 1928. To add new material, two supplements were issued after this, the first in 1933, and another, more extensive one between 1972 and 1986. In 1989, the Oxford English Dictionary, second edition (OED2) was published, which integrated the material from the original dictionary and the supplements into a single alphabetical sequence. However, virtually all material contained in this edition still remained in the form in which it was originally published. This is the edition most commonly used today, as it forms the basis of the Oxford English Dictionary Online and is also still being sold in print and on CD-ROM. In 1991, a new project started to revise the entire dictionary and bring its entries up to date, both in terms of English usage and in terms of associated scholarship, such as encyclopaedic information and etymologies. The scope was also widened, placing a greater emphasis on English spoken outside Britain. The revision of the dictionary began with the letter M, and the first updated entries were published online in March 2000 (OED3). Quarterly publication of further material has extended the range of revised entries as far as PROTEOSE n. (June 2007). New words from all parts of the alphabet have been published alongside the regular revision.[...]

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Horswill, Catharine. "The relative importance of opposing drivers in determining population change in macaroni penguins Eudyptes chrysolophus." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/5979/.

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It is widely recognised that both nutrient-driven processes acting from the “bottom-up” and predator-driven processes acting from the “top-down” are important drivers of population change. However, studies that examine how these joint forces influence the population dynamics of oceanic species are lacking. In the Antarctic and Sub-Antarctic ecosystem, human-mediated changes have driven biological change at both ends of the food chain; rapid regional warming at the bottom and heavy exploitation of apex predator populations at the top. Consequently, many populations of marine predators have rapidly changed in size over the last 50-years. Unravelling the effects of bottom-up and top-down forcing on these open ocean ecosystems, has thus been highlighted as an immediate priority for polar scientists. The overall aims of this study were to use demographic, environmental and diet data to unravel the processes that contributed to a population of macaroni penguins at South Georgia declining rapidly between 1985 and 2012. I use mark–recapture modelling to examine the survival rates of macaroni penguins. Over 10 years, birds were marked with subcutaneous electronic transponder tags and re-encountered using an automated gateway system fitted at the entrance to the colony. These findings were combined with a 28-year time series of population counts and productivity measurements in an age-structured state-space population model to disentangle the processes underlying the observed population decline. Finally, I combined stable isotope analysis and tracking data to investigate the individual strategies macaroni penguins might employ to mitigate the effects of density-dependence during the breeding season. Macaroni penguins at South Georgia declined at 6% per year between 1985 and 2000, stabilising thereafter. This study indicates that the population declined in response to recruitment rates being lower than adult mortality. This trend was potentially accelerated by three large mortality events that were possibly associated with top-down predation pressure from giant petrels. Survival rates were low and variable during the fledging year, increasing to much higher levels from age 1 onwards. Year-to-year variability in demographic rates was induced by a combination of individual quality, top-down predation pressure and bottom-up environmental forces. The relative importance of these covariates on survival rates was age-specific, whereby predation pressure had a considerably greater effect during the fledgling year compared with birds older than 1-year. The population trajectory stabilised after 2000 in response to an increase in survival, as well as density-dependent feedbacks upon productivity. In order to minimise the effects of density-dependence during the breeding season and optimise daily energy expenditure, macaroni penguins appeared to make distinct dietary choices that remained highly consistent from year-to-year. Individually specialised foraging strategies occurred in response to seasonal variations in foraging range, conspecific density and prey availability at the foraging sites. The future stability of this population will depend on the carrying capacity of the environment supporting productivity rates at their present level, and the population size and breeding success of giant petrels not increasing so that adult survival rates can remain stable. More broadly, this study highlights the importance of considering multiple causal effects across different life-stages when examining the demography of seabirds, and demonstrates the additional insights that can be gained by using models with increased precision.

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Saraux, Claire. "Response of penguins to environmental changes across the Southern ocean : from individuals to population trends." Strasbourg, 2011. http://www.theses.fr/2011STRA6192.

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Le changement climatique, dorénavant sans équivoque, devrait se poursuivre voire s’amplifier dans les siècles à venir, affectant profondément la composante biologique de notre planète. Il est donc nécessaire et urgent de mieux comprendre les écosystèmes et leurs réponses face au changement climatique. Au cours de cette thèse, j’ai étudié l’effet du climat dans l’Océan Austral au travers des manchots. Ceux-ci sont souvent considérés comme de bons indicateurs de leurs écosystèmes de part leur position au sommet de la chaîne trophique. Ce travail repose sur des données pluriannuelles collectées sur 3 espèces de manchots à l’aide de systèmes de suivi automatique, visant à minimiser la perturbation par rapport à la méthode habituelle des bagues alaires. Ainsi, nous montrons des effets contrastés du climat sur les différents traits d’histoire de vie chez les manchots royaux, dont la survie juvénile augmentait les années où la température de surface de la mer était élevée, au contraire de la survie adulte et du succès reproducteur. De plus, nous soulignons l’importance de l’échelle temporelle à laquelle on étudie cet effet du climat et la nécessité de l’adapter à la biologie de l’espèce. La mortalité des poussins de manchots pygmées est par exemple concentrée sur quelques semaines, indiquant que le succès reproducteur dépend chez cette espèce de conditions ponctuelles et non des moyennes saisonnières généralement utilisées. Enfin, les capacités différentes des individus à faire face à des conditions de glace variables, observées chez le manchot Adélie, montrent la nécessité de prendre en compte les différences interindividuelles en vue d’une potentielle adaptation des manchots
Climate change is now unequivocal and foreseen to continue within the next centuries, profoundly affecting the biological component of our planet. Thus, it is becoming urgently necessary to increase our understanding of ecosystems and their responses to climate change. In this thesis, we investigated the effects of climate on Southern Ocean ecosystems through the monitoring of penguins. As top-predators, penguins are often considered good indicators of their environment by integrating the effects of climate which occur lower in the food chain. Data were collected over several years on 3 penguin species (little, king and Adélie penguins) using automatic monitoring systems, that we proved to be relatively harm-free compared to the usual but deleterious flipper-banding method. We found king penguin juvenile survival to increase in years of high sea surface temperature by opposition to previous results on adult survival and breeding success, indicating contrasted effects of climate depending on life-history traits. Also, we highlighted the importance of the time-scale at which the effect of climate is investigated and the necessity of adapting it to the species biology. In little penguins, chick mortality was concentrated on some weeks, underlining the dependence of breeding success on punctual conditions instead of the mostly used mean seasonal conditions. Finally, we showed the importance of individual heterogeneity, leading for instance to differences in the ability to face various sea-ice conditions in Adélie penguins. Such inter-individual differences along with behavioural flexibility may play a role in a potential penguin adaption through phenotypic plasticity

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Wienecke, Barbara C. "The size and breeding patterns of Little Penguins Eudyptula minor in Australia: A comparative study." Thesis, Wienecke, Barbara C. (1993) The size and breeding patterns of Little Penguins Eudyptula minor in Australia: A comparative study. PhD thesis, Murdoch University, 1993. https://researchrepository.murdoch.edu.au/id/eprint/53080/.

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The breeding regime of Little Penguins Eudyptula minor was studied on Penguin Island, Western Australia, from January 1990 to December 1992. Data from 1986 to 1989 were also available for analysis. Little Penguins at Penguin Island laid eggs over a very protracted period, which commonly extended from late April to early November. Two peaks of laying occurred in several of the years studied. The onset of first laying was strongly influenced by temperatures over 30° C but was independent of breeding success in the previous season. Body condition in adults was correlated with total rainfall, possibly through storm events. The sizes and weights of eggs did not differ significantly between years nor differ between the first and second eggs in a clutch. The numbers of eggs which hatched and the numbers of chicks which fledged varied significantly between years. Overall breeding success was less than 50 % (21 - 48 %). On average, each breeding adult produced 0.48 young per year. Annual survival of adults was estimated as 75 % giving an average breeding life time of 4.8 years. Of those banded as chicks, 67.5 % returned at two or three years old. Banding recoveries were up to 283 km distant but 69 % were within 10 km of the colony. Significantly more individuals returned to the same nest when they remained with the same partner and when they bred successfully in the previous year. Growth constants of chicks did not differ significantly between years or between first and second chick in a brood. The tarsus grew faster than the flipper and beak. Morphometric analyses showed that Little Penguins from Penguin Island arid the White-flippered Penguins from New Zealand both to be larger than Little Penguins from Tasmania and the eastern mainland of Australia. The most similar, morphometrically, were those at Jarvis Bay, Phillip Island, Tasmania and Albany. Comparison of DNA of Little Penguins appeared to support this scenario although genetic results are necessarily tentative due to the small sample sizes.

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Stedt, Johan. "Parasitizing behavior of Ixodes uriae ticks on Chilean Magellanic penguin (Spheniscus magellanicus) and their importance as pathogen vectors." Thesis, Högskolan i Kalmar, Naturvetenskapliga institutionen, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hik:diva-2356.

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Ticks are vectors for a larger number of viruses and bacteria than all other arthropod taxa, including mosquitoes. In Europe is it foremost Borrelia spirochetes and the Flavivirus Tick-borne Encephalitis virus that cause disease in humans. In this study, the tick species Ixodes uriae has been studied. I. uriae have a circumpolar distribution in both hemisphere and can be found both in Arctic and Antarctica. I collected ticks from Magellanic penguins in south Chile and analyzed them to see if they carry Borrelia spirochetes or Flavivirus. Totally were 218 ticks collected from 165 controlled penguins. All ticks were collected from adult penguins and the parasitizing ticks were all found in the auditory meatus which is a new phenomena compared to earlier studies. Both Borrelia spirochetes and Flavivirus were found in the collected ticks using PCR techniques. This is an interesting result since not much research has been performed in this geographical area before. Until date there is only one species of Borrelia (Borrelia garinii) found in I. uriae on the southern hemisphere and new Flavivirus is regularly found around the world. Unfortunately we have not been able to determine species of the Borrelia spirochetes or Flavivirus so far but this work will be continued.

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Acosta, Igor da Cunha Lima. "Pesquisa de coccídios da família Sarcocystidae em pinguins-de-magalhães (Spheniscus magellanicus) encalhados na costa brasileira." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-06022018-145818/.

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O gênero Sarcocystis é constituído por várias espécies que se diferenciam pelas características morfológicas, biológicas e moleculares. Foram relatadas mais de 196 espécies encontradas em mamíferos, aves e répteis e somente 26 dessas espécies possuem o ciclo completo conhecido. Toxoplasma gondii é um parasito intracelular obrigatório, com distribuição geográfica cosmopolita, capaz de infectar uma ampla variedade de mamíferos e aves, inclusive o homem, caracterizando seu potencial zoonótico. Nas últimas décadas, a quantidade de pinguins vindos da Patagônia argentina e chilena, região de nascimento dessas aves, para o litoral brasileiro, onde muitos encalham e são resgatados, tem aumentado significativamente. Pouco se sabe sobre as doenças causadas por protozoários nessas aves. O presente estudo teve como objetivo conhecer aspectos epidemiológicos da infecção por coccídios da família Sarcocystidae em pinguins-de-magalhães (Spheniscus magellanicus), através de análises moleculares e sorológicas. Foram realizadas duas campanhas, uma em 2014 e outra em 2015, com a finalidade de obter amostras de sangue e tecidos dos pinguins que vieram a óbito durante reabilitação no Instituto de Pesquisa e Reabilitação de Animais Marinhos (IPRAM) localizada em Cariacica, Espírito Santo. Foram colhidas 514 amostras de tecidos (músculo=342, coração=86, cérebro=86) de 310 indivíduos. Dos tecidos de 54 pinguins foi realizado o bioensaio em camundongos para o isolamento de T. gondii, mas nenhum isolado foi obtido. Amostras de 310 indivíduos tiveram o DNA extraído para a pesquisa de coccídios da família Sarcocystidae utilizando-se os marcadores 18S rDNA, espaçador interno transcrito 1 (ITS1), codificador de proteínas de superfície (SAG)2, SAG3 e SAG4, subunidade beta da RNA polimerase (RPOB) e citocromo B (CytB). Destas, 16 (3.0%) amostras de músculo peitoral foram positivas para o gênero Sarcocystis spp., quando analisadas pelo marcador 18S, e todas com resultados idênticos. Com o ITS1, RPOB e Ctv. foram confirmadas as espécies de Sarcocystis em 12 amostras, todas idênticas a S. falcatula-like. Com os marcadores SAGs foi possível observar que as sequências não tinham variabilidade genética. Das 145 amostras de soro avaliadas para a presença de anticorpos anti-T. gondii, pelo Teste de Aglutinação Modificado (MAT ≥20), 18 aves foram positivas com títulos de: 20 (7 aves), 40 (9 aves) e 80 (2 aves). Este é o primeiro relato de S. falcatula-like e de anticorpos anti - T. gondii em pinguins-de-magalhães de vida livre.
The genus Sarcocystis is composed of several species that are differentiated by the morphological, biological and molecular characteristics. More than 196 species found in mammals, birds and reptiles have been reported, and only 26 of these species have the complete known cycle. Toxoplasma gondii is an obligate intracellular parasite with cosmopolitan geographic distribution, capable of infecting a wide variety of mammals and birds, including man, characterizing its zoonotic potential. In recent decades, the number of penguins that have come from Argentine and Chilean Patagonia, the region of birth of these birds, to the Brazilian coast, where many of them are stranded and rescued, has increased significantly. Little is known about the diseases caused by protozoa in these birds. The present study had as objective to study epidemiological aspects of coccidia infection of the family Sarcocystidae in Magellanic Penguins (Spheniscus magellanicus), through molecular and serological analyzes. Two campaigns were carried out, one in 2014 and another in 2015, in order to obtain blood and tissue samples from penguins who died during rehabilitation at the Institute of Research and Rehabilitation of Marine Animals (IPRAM) in the municipality of Cariacica, Espírito Santo. Tissue samples (total = 514: muscle = 342, heart = 86, brain = 86) were collected from 310 birds. From the tissues of 54 penguins the mouse bioassay was performed for the isolation of T. gondii, but no isolates were obtained. Samples of 310 individuals had DNA extracted for coccidia from the Sarcocystidae family using the 18S rDNA, Transcribed internal spacer 1(ITS1), surface protein encoder (SAG)2, SAG3, SAG4, beta subunit of RNA polymerase (RPOB) and citocrome B (CytB) markers. Of these, 16 (3.0%) samples, of pectoral muscle, were positive and all were identical to Sarcocystis spp. when analyzed by the 18S marker. With ITS1, RPOB and CytB the Sarcocystis species were confirmed in 12 samples, all identical to S. falcatula-like. With the SAGs it was possible to observe that the sequences had no genetic variability. Of the 145 serum samples evaluated for the presence of anti-T. gondii antibodies by Modified Agglutination Test (MAT ≥20), 18 were positive with titers of: 20 (7 birds), 40 (9 birds) and 80 (2 birds). This is the first report of S. falcatula-like and the presence of antibodies to T. gondii in free-living magellanic penguins.

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Dehnhard, Nina [Verfasser]. "Adaptations to a variable environment - feeding ecology, survival and physiology of southern rockhopper penguins / Nina Dehnhard." Konstanz : Bibliothek der Universität Konstanz, 2013. http://d-nb.info/1088447554/34.

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Scheffer, Annette. "Foraging behaviour of king penguins (Aptenodytes patagonicus) in relation to oceanography at South Georgia and Kerguelen." Thesis, Open University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590808.

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Understanding the levels of variability in oceanographic features where marine predators forage is critical for understanding variability in an animal's foraging behaviour and reproductive success, and for assessing their potential reactions to environmental change. In this thesis, I examine the foraging behaviour of king penguins (Aptenodytes patagonicus) in relation to oceanographic features in both horizontal and vertical dimensions. I used ARGOS and Global Positioning System tracking data combined with Time-Depth-Temperature-Recorder data to follow the at-sea movements for penguins breeding at South Georgia and Kerguelen. Combining penguin behaviour with oceanographic data at the surface and at depth allowed me to explore how animals adjust their horizontal and vertical movements in response to their environment. In this context J investigated how horizontal habitat use may relate to different Antarctic Circumpolar Current frontal zones, and how hydrological structures at depth may impact diving behaviour. At both study locations, the Polar Front (PF) and cold-water features of southern origin were key features used during foraging. The importance of local habitat was reflected in their use of mesoscale eddies at South Georgia, and bathymetry-related upwelling at Kerguelen. The main features used at depth, during prey pursuit, were the thermocline and Winter Water. Penguins also explored Circumpolar Deep Water, which appears to represent an important foraging niche for birds when under increased breeding or environmental constraints. Variability in the PF and in cold-water features in the foraging area significantly affected penguin behaviour. For example, penguins showed altered behavioural responses and low reproductive success following shifts in key oceanographic features during one breeding season. My study of king penguin foraging behaviour in two sectors of the Southern Ocean has generated these key insights into foraging relationships with oceanography, and into penguin's adaptive capacities to environmental variability. This is of importance for assessing possible reactions of king penguins towards environmental change.

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Hibbets, Eric Matthew. "Molecular Characterization of Hybridization Between Magellanic (Spheniscus magellanicus) and Humboldt (Spheniscus humboldti) Penguins in the Wild." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1562071641076803.

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Campbell, Katrina. "Factors influencing the foraging behaviour of African Penguins (Spheniscus demersus) provisioning chicks at Robben Island, South Africa." Doctoral thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/23050.

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Urgent and effective conservation is needed to halt the declines of endangered African Penguins. A purse-seine fisheries closure zone was in place out to 20 km around Robben Island for three years. It provided an opportunity to investigate penguin foraging behaviour in relation to estimated local prey abundance and other factors without the confounding variable of local fishing. Penguins provisioning chicks were equipped with GPS temperature depth devices for a foraging trip. Dive data (N = 75) and GPS tracks (N = 78) were collected from 78 penguins. Of those, 14 penguins were at-sea within two days of a fine-scale hydro-acoustic pelagic fish survey. Diet sampling, breeding success and chick body condition monitoring took place in the colony. Nests were followed to outcome. Morphological indicators were developed for sex determination and body condition. Intrinsic factors, brood mass, prey abundance, wave height and direction were explored in respect to foraging behaviour. Kernel density analysis identified foraging areas, confirming consistent use of the closure area. Annual differences in foraging effort were explained by variation in local prey abundance. The time the penguins spent diving and the distance travelled from the colony were negatively related to local prey abundance. There was greater variation in foraging distance when prey abundance was lower. Foraging areas and dive behaviour were similar for the sexes. The survival of chicks in the foraging study did not differ from chicks monitored in the colony for breeding success (control chicks). The trips of penguins with nesting success (N = 44) were on average 4.5 km closer to the colony than the penguins that had nesting failure (N = 21). Chick body condition in the colony was positively related to the Anchovy (Engraulis encrasicolus) mass percentage in the diet and the local pelagic fish abundance; condition was predicted to vary by 245% over the range of local fish abundance observed during the study period (0.5 to 187 thousand tonnes). Identifying ways to avoid depletion of prey resources around penguin colonies is important for conservation of the species.

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Levenson, David H. "The visual pigments of diving tetrapods : genetic and electroretinographic investigations of pinnipeds, cetaceans, sea turtles, and penguins /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2004. http://wwwlib.umi.com/cr/ucsd/fullcit?p3120446.

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Hernandez, Santibanez I. "Space and politics in the 'Penguins' movement : geographies of the political construction of the Chilean student movement." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1549607/.

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In 2006, Chilean secondary students, known as the Penguins because of their black and white school uniform, mobilised across the country to demand that education should be a right, not a privilege. Notwithstanding the political and academic debate they triggered regarding an unresolved agenda of equity and quality education, scholarship relating to the Penguins has been limited to analysing their external consequences. They remain a ‘failed’ student movement, since their demands were met with only limited technocratic reforms. This thesis examines the Penguins’ movement as a constructive process of collective identity no longer framed within limited political influence. It explores the origins of the movement and analyses how space and politics form the basis for its collective identity. It investigates elements of continuity and discontinuity in the 2011 student movement against the neoliberal market-oriented education system. Empirical data on the Penguins’ movement was collected through in-depth interviews with student activists, teachers, policy-makers and academics, and through secondary sources including official documents, academic editorials, and newspapers. Constructivist grounded theory was employed to develop an inductive comparative analysis of space and politics in the movement. Geography structures the construction of the Penguins’ movement. Spatialities of social mixing and a historical urban educational inequality are intricately linked to different geographies of student political activism. Prefiguration of politics in everyday practices is a key component for building a more egalitarian political movement. However, school occupations in 2006 became the specific places where collective identity and new territorialities evolved. The Penguins’ collective identity detaches the movement from the idea of failure and links with territorialities through which the demand for free, public quality education for all is re-envisioned in spatial rather than temporal terms. Further questions about the potential of the Chilean student movement to lead a political project for social transformation are also considered.

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Dissertations / Theses on the topic 'Penguins'

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