To see the other types of publications on this topic, follow the link: Behavioural ecology.

Dissertations / Theses on the topic 'Behavioural ecology'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 dissertations / theses for your research on the topic 'Behavioural ecology.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.

1

De, Bourcier P. G. R. "Synthetic behavioural ecology." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360517.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

McCormick, Joseph. "Information cascades in behavioural ecology." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/28578.

Full text
Abstract:
In ecology, information cascades have been used to explain a variety of collective behaviours, including mate selection, anti-predatory responses, and social foraging. Taxonomically diverse, information cascades occur in many group-living animals, including ant colonies, schools of fish, bird flocks, and social mammals. In this thesis, I studied the form and function of information cascades that drive a wide variety of group-level behaviours. In chapter one, I surveyed and reviewed the published literature regarding information cascades in biological systems. I discuss a selection of past studies to illustrate the diversity of information cascades, highlighting the adaptive significance and fitness consequences of different cascade types. I build a conceptual framework inspired by the variation in outcome and structure of information cascades elicited under different environmental or informational conditions. In chapter two, I experimentally tested the impact of maladaptive information cascades on the foraging performance of ants (Pheidole rugosula). Here, I introduced misinformation into foraging networks and measured the ants’ ability to re-establish foraging activity. I find that colonies readily recover and maintain robust foraging efforts when faced with erroneous social information. Overall, I find that information cascades drive critical collective behaviours in a diverse range of animal taxa. I also find that P. rugosula avoids significant maladaptive cascades despite the introduction of misinformation into their foraging networks. Information cascades warrant further research to improve our understanding of their role in nature and to decipher potential insights into managing information cascades in human systems.
APA, Harvard, Vancouver, ISO, and other styles
3

Clegg, Mark Robert. "Behavioural ecology of freshwater phytoplanktonic flagellates." Thesis, Lancaster University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403729.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Marsh, Frances J. "The behavioural ecology of young baboons." Thesis, University of St Andrews, 1993. http://hdl.handle.net/10023/15097.

Full text
Abstract:
It is hypothesised that young baboons are potentially vulnerable to the effects of seasonal stress. Data were collected on the behaviour of this age group during a 12 month field study of a troop of olive baboons (Papio anubis) on the Laikipia plateau, Kenya, using a hand-held computer and a new program written by the author. Long-term environmental records for this site were continued. At this site there is a seasonal pattern of rainfall with inter-annual variation. Measures of biomass indicate that there are seasonal fluctuations in baboon food availability. Patterns in the occurrence of one component of the baboon's diet, Acacia species, are presented. The varying behaviour of the troop as a whole is related to food availability. Differential use of the home range and observed sub-trooping behaviour are interpreted as adaptive strategies for living in a seasonal environment. Developmental change in the behaviour associated with the mother-offspring relationship is described. Patterns in the time spent in contact with and close proximity to the mother from this site are compared with those from other sites, and striking similarities are found. Many of the behavioural activities of infants and young juveniles, i.e. feeding, moving, types of exploring, visually attending, grooming, and receiving affiliative approaches, exhibit patterns of developmental change. Interactions between activities are examined in the context of the complete activity budget. The effect of seasonal stress on young baboons is examined by using a technique of curve fitting. Data are compared between periods of higher and lower food availability. Significantly more time is spent feeding and less time spent in social and attending activities in the 'worst' than the 'best' months. Young baboons vary their diets seasonally. There is evidence that older infants (weanlings) are more vulnerable to the impact of seasonal stress than either young infants or young juveniles.
APA, Harvard, Vancouver, ISO, and other styles
5

Dowling, Damian Kimon. "Behavioural ecology of the red-capped robin." Connect to thesis, 2004. http://eprints.unimelb.edu.au/archive/00000798.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Robinson, Mark Francis. "The behavioural ecology of the serotine bat." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334221.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Russell, Avery L., Sarah J. Morrison, Eleni H. Moschonas, and Daniel R. Papaj. "Patterns of pollen and nectar foraging specialization by bumblebees over multiple timescales using RFID." NATURE PUBLISHING GROUP, 2017. http://hdl.handle.net/10150/622868.

Full text
Abstract:
The ecological success of social insects is frequently ascribed to improvements in task performance due to division of labour amongst workers. While much research has focused on improvements associated with lifetime task specialization, members of colonies can specialize on a given task over shorter time periods. Eusocial bees in particular must collect pollen and nectar rewards to survive, but most workers appear to mix collection of both rewards over their lifetimes. We asked whether bumblebees specialize over timescales shorter than their lifetime. We also explored factors that govern such patterns, and asked whether reward specialists made more foraging bouts than generalists. In particular, we described antennal morphology and size of all foragers in a single colony and related these factors to each forager's complete foraging history, obtained using radio frequency identification (RFID). Only a small proportion of foragers were lifetime specialists; nevertheless, >50% of foragers specialized daily on a given reward. Contrary to expectations, daily and lifetime reward specialists were not better foragers (being neither larger nor making more bouts); larger bees with more antennal olfactory sensilla made more bouts, but were not more specialized. We discuss causes and functions of short and long-term patterns of specialization for bumblebee colonies.
APA, Harvard, Vancouver, ISO, and other styles
8

Pagès, Fauria Jordi. "A behavioural seascape ecology approach to macrophyte herbivory." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/126622.

Full text
Abstract:
Overall, this thesis aims at approaching macrophyte herbivory and community ecology from a behavioural landscape perspective. Our study system, the seascape mosaic of Posidonia oceanica seagrass meadows interspersed with sand patches and rocky areas with macroalgal cover, is particularly useful to test sound ecological questions. In essence, the macroherbivore community is made up of just two key species, the sea urchin Paracentrotus lividus and the fish Sarpa salpa. Both species are generalists and have been found to actively consume seagrass and macroalgae, profoundly altering habitat structure. Moreover, both animals differ in their mobility and in the predation risk they are subjected to, which poses interesting questions on how they will perceive, use, respond to and impact their surrounding seascape. S. salpa is a highly mobile species with few known extant predators, while the sea urchin P. lividus is a low mobility species with high rates of predation. The thesis is structured in five chapters that focus on different aspects of community organization and ecological interactions (chapter 4), animal movement (chapters 5 and 6), animal risk assessment and behavioural responses to predation risk (chapter 5), habitat selection and connectivity (chapter 6), influence of seascape attributes on herbivore foraging and thus on herbivores’ impacts on plants (chapter 7) and herbivores’ responses in terms of population and behaviour to disturbances (chapter 5). Chapters derive from field manipulative experiments (chapter 4), field mensurative campaigns (chapters 6, 7 and 8) or controlled experiments in the laboratory (chapter 5). In chapter 4 we observed that predation pressure on a key herbivore (sea urchin) can be modified both by the environmental context within which it finds itself and by the actions of another herbivore (S. salpa) that modifies the plant traits that create this environmental context (P. oceanica). Herbivores, particularly when acting as ecosystem engineers, may have the potential to mediate and increase predation risk, as they substantially modify habitat structure with consequences for refuge availability, among others. Indeed, this type of interactions may be stronger or softer according to prey movement patterns and their perception of risk. Sea urchins can perceive predator chemical cues and respond escaping from these stimuli altering their behaviour by switching among different movement patterns. Predation risk may be as important in determining animal movement patterns as feeding strategies, and in chapter 5 sea urchins responded with straighter paths in the presence of predator cues. We were also interested in the movement patterns of the other key herbivore of the system (chapter 6). The herbivorous fish S. salpa displayed large home ranges and connected distant habitats with their highly mobile behaviour. In spite of their mobility, they also displayed a strong selectivity for the seagrass habitat, which was preferred over the rocky and sand areas. Highly mobile species can connect distant habitats, and may perceive the landscape at a greater scale. The knowledge gained on the movement patterns of both herbivore species allowed us to assess the influence of seascape attributes on the herbivory patterns found in P. oceanica seagrass meadows. The observed spatial heterogeneity in the herbivory process may be mediated by the interaction of mobility of the two main herbivores (sea urchin and fish) with seascape configuration and predation risk. We finally proved that herbivores’ species-specific behaviour could lead to contrasting responses in the face of extreme storm events. Under catastrophic disturbances, the presence of different responses among the key herbivores of the system may be critical for the maintenance of functions. Differences in species behaviour and movement capacities explain why the most mobile species (in our case S. salpa) have the possibility to endure extreme storms, while the low-mobility species is subject to great population losses just relying on the structural complexity of the habitat to resist. Overall, we feel convinced that merging the behavioural and landscape approaches can result in new views in the ecology of functions such herbivory, in which at least two species interact among themselves framed by a given landscape configuration.
Aquesta tesi pretén aproximar-se a l’estudi de l’herbivorisme dels macròfits marins i a l’ecologia de comunitats des d’un punt de vista comportamental i de paisatge. Volem estudiar com en un sistema relativament senzill, els dos herbívors claus (el peix Sarpa salpa i la garota Paracentrotus lividus) interactuen entre ells, i com els seus aspectes comportamentals interactuen també amb la configuració del paisatge i l’hidrodinamisme. El nostre sistema d’estudi és el paisatge format per praderes de la planta marina Posidonia oceanica barrejades amb àrees de sorra i zones rocoses amb macroalgues. La tesi s’estructura en cinc capítols. El primer tracta de com la pressió de depredació sobre un herbívor clau (garotes) pot ser modificada tant pel context ambiental en què es troba com per les accions de peixos herbívors (salpes) que modifiquen els trets de la planta marina (posidònia) que crea aquest context ambiental. Aquestes interaccions seran més o menys intenses en funció de com reaccionin els individus presa davant dels depredadors. Per això vam estudiar el comportament de les garotes en funció de la presència o absència de senyals químics de depredadors. Vam observar que responen amb canvis en els seus patrons de moviment, amb trajectòries més rectilínies en presència de depredadors. També ens interessava entendre els patrons de moviment de l’altre herbívor del sistema, el peix S. salpa. Els nostres resultats mostren que aquest peix herbívor presenta grans àrees de campeig i que té la capacitat de connectar hàbitats distants gràcies a la seva gran mobilitat. Alhora, les salpes mostren una gran selectivitat per l’habitat de P. oceanica, que sembla clarament preferit sobre les àrees rocoses i de sorra. Els coneixements obtinguts sobre els moviments dels eriçons i les salpes ens van permetre estudiar la influència dels atributs de paisatge en l’herbivorisme en praderes de P. oceanica. L’heterogeneïtat espacial observada en l’herbivorisme és produïda, possiblement, per la interacció entre la mobilitat dels dos herbívors principals del sistema (garotes i salpes), la configuració del paisatge i el risc de depredació. Finalment, vam poder comprovar que les diferències de comportament observades entre els dos herbívors estudiats van implicar respostes dispars de les dues espècies davant una tempesta extrema, cosa que pot ser crítica pel manteniment de les funcions ecosistèmiques. En conjunt, estem convençuts que la unió dels punts de vista que aporten l’ecologia del comportament i l’ecologia del paisatge poden resultar en una millor i més completa comprensió de funcions ecològiques com l’herbivorisme, en les quals almenys dues espècies interaccionen incloses en un paisatge determinat.
APA, Harvard, Vancouver, ISO, and other styles
9

Schöning, Caspar. "Evolutionary and behavioural ecology of Dorylus army ants." [S.l. : s.n.], 2004. http://www.diss.fu-berlin.de/2004/122/index.html.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Sillero, Zubiri Claudio. "Behavioural ecology of the Ethiopian wolf, Canis simensis." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239356.

Full text
APA, Harvard, Vancouver, ISO, and other styles
11

Herrera, E. A. "The behavioural ecology of the capybara, Hydrochoerus hydrochaeris." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375233.

Full text
APA, Harvard, Vancouver, ISO, and other styles
12

Batchelor, Timothy Peter. "Parasitoid interactions in behavioural ecology and biological control." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/11176/.

Full text
Abstract:
This thesis presents laboratory investigations on the competitive interactions which take place within and between bethylid parasitoids. Part one investigates the compatibility of three bethylids (Cephalonomia hyalinipennis, Cephalononlia stephanoderis and Prorops nasuta) for biocontrol releases against the principal pest of coffee, the coffee berry borer (CBB), Hypothenemus hampei. Cephalonomia hyalinipennis is able to hyperparasitise and consume pupae of C stephanoderis and P. nasuta. Cephalonomia stephanoderis also engages in intra-guild predation, consuming pupae of C hyalinipennis. In contests for CBB hosts, fatal fighting occurs in 69% of inter-specific replicates but never occurs in intra-specific replicates. This suggests that interspecific competition is stronger than intraspecific competition and that species coexistence may be compromised. Cephalonomia tephanoderis is the superior interspecific contestant while P. nasuta is the least successful and never kills an opponent. Where CBB infested coffee berries are provided to the three bethylids, coexistence between species is possible, but rare, within a single coffee berry. Prorops nasuta is the most successful species in interspecific replicates and replicates containing C. hyalinipennis generally have low production, regardless of the species combination added. Part two investigates contest interactions, the variables that influence contest outcome between Goniozus nephantidis females and chemical release. Prior ownership and difference in contestant weight have positive influences on contest outcome. Host weight positively influences the outcome of contests between two 'owners' and 'intruder' take-over success increases when intruders are older than owners. Seven bethylid species are found to release volatile chemicals when stressed. A pilot study identifies the volatile chemical in G. nephantidis and employs Atmospheric Pressure Chemical Ionisation-Mass Spectrometry for real-time analysis of chemical release during contest interactions. The appendix contains an advanced investigation using this technique. Bethylids are useful model organisms for the study of competitive interactions but appear to be generally ineffective as biological control agents.
APA, Harvard, Vancouver, ISO, and other styles
13

Williamson, Elizabeth A. "Behavioural ecology of Western Lowland Gorillas in Gabon." Thesis, University of Stirling, 1988. http://hdl.handle.net/1893/1314.

Full text
Abstract:
The behavioural ecology of western lowland gorillas was studied for 16 months in the Lope Reserve, Gabon, where gorillas are sympatric with chimpanzees in lowland tropical forest. Data were collected by direct observation, and by examination of nest-sites, feeding-sites, and trails. The nature of frugivory and the extent of seasonal variation in food selection were emphasised. Dietary composition was identified, and the contribution of fruits was evaluated from the volume of fruit ingested estimated retrospectively from seeds in the gorillas' dung. Forest structure and composition were assessed using transects, and fruit and leaf production was quantified monthly to estimate food availability. Food distribution was patchy, and many foods showed seasonal peaks in abundance. The heterogeneity of the habitat was reflected in the diverse diet: gorillas ate 139 parts of 103 species of plants, including 78 fruits. One third of dung samples contained weaver ants. Vegetative parts of Aframomum and Marantaceae formed staple foods, due to their abundance, accessibility, and year-round availability. Succulent fruit formed over 90% of fruit intake. Seasonal variation was measured in all dietary parameters. Flexible foraging strategies enabled gorillas to cope with fruit scarcity, particularly during the major dry season: when less fruit was available gorillas consumed more stems, leaves, and bark, and ate poorer-quality fibrous fruits. Ranging was influenced by the seasonal availability of particular food species: when fruit was abundant gorillas travelled large distances between sources, when scarce they adopted a low cost strategy, shifting their diet towards more abundant, but poorer quality foods, and travelling less. Differences in feeding, ranging, and climbing between lowland and mountain gorillas result from striking differences in their respective habitats, especially in the abundance and distribution of fruit sources. Lowland gorillas' home ranges were larger; they spent more time in tress, mostly feeding; yet their social structure seemed to be similar to mountain gorillas. Lope gorillas adopted strategies similar to those of other frugivorous primates: fruits were preferred foods, consumed with fibre and leaves to meet nutritional requirements. The switch in diet was facilitated by the gorillas’ large body-size, which may have enabled them to cope with succulent fruit shortages, and allowed gorillas to remain in relatively stable groups.
APA, Harvard, Vancouver, ISO, and other styles
14

Taber, Andrew B. "The behavioural ecology of the mara, Dolichotis patagonus." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:3caf10ab-ac34-4bbe-b906-fa495c40f7b8.

Full text
Abstract:
This thesis presents the results of a 3 year field study on the behavioural ecology of the mara on the Valdés Peninsula in Argentina. The main goal was to investigate why the mara's social system incorporates both monogamy and communal denning, a combination unknown in other mammals. The research techniques used were behavioural observations and radio-tracking. Radio-tracking of 9 maras revealed that pairs were continually moving into new areas, suggesting that their ranging behaviour is adapted to an irregular pattern of resource distribution. Two maras had prevailing ranges of 35 ha and moved yearly over about 200 ha. Ranges floated around a geographic centre. One constraint on the animals' movements may be the need to stay near a den site for pupping. Maras were diurnal, and spent on average 46% of the day grazing. Ranges may overlap up to 33%, but range use between neighbouring pairs were negatively correlated suggesting that animals were avoiding each other--pairs may be occupying floating territories. Evidence that maras are monogamous in the wild is presented. The factors leading to monogamy are argued to be: (i) females are irregularly dispersed because of the distribution of food; and (ii) the brevity of the female's oestrus (1-2 hrs). A male attempting to mate polygynously would have difficulties in finding and securing a female; thus males may do best by staying with one female to ensure a successful mating. Males may enhance their reproductive success by watching for predators so that their females can spend more time feeding to meet the energetic demands of lactation and gestation. During the pupping season, August to January, groups of 1 to 22 pairs gather at single dens. Several dens may be located near each other to form denning communities. Most pairs produce only one litter a year and there is a peak of births in September and October. Pairs visit the den once a day for a period of 5-6 weeks to nurse their young. Den sites are not limited; and the reason maras den communally appears to be the increased protection from predators accruing to pups and adults in larger groups. Two possible routes are suggested in the evolution of the mara's social system: (i) from a monogamous starting point it has become advantageous to creche pups; or (ii) ancestral maras were more colonial and probably polygynous, but have been forced to space out because of changes in the distribution of food, which has led to monogamy. Finally, maras were compared with other caviomorph rodents, lagomorphs, and monogamous ruminants and were shown to be most similar to the latter in their adaptations to the environment a remarkable example of convergent evolution.
APA, Harvard, Vancouver, ISO, and other styles
15

Prenter, John. "Behavioural ecology of the autumn spider Metellina segmentata." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357461.

Full text
APA, Harvard, Vancouver, ISO, and other styles
16

Johnson, I. P. "Behavioural ecology of the Canada Goose (Branta canadensis)." Thesis, University of Reading, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373840.

Full text
APA, Harvard, Vancouver, ISO, and other styles
17

Thompson, David. "Behavioural ecology and physiology of diving in seals." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367657.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

De, Winter Gunnar. "The ecology and evolution of individual behavioural variation." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/44995/.

Full text
Abstract:
Central to this thesis is the investigation of how several factors (e.g. morphology, ecology, and social conditions) co-vary with consistent individual behavioural variation. Additionally, conceptual work explores the reach of consistent inter-individual behavioural variation in several novel contexts. In doing so, the aim is to contribute novel findings to the quickly growing compendium of knowledge concerning 'animal personality' in various settings. In summary, during this PhD the following research has been performed: • Through the use of lab-reared juvenile three-spined stickleback (Gasterosteus aculeatus) whose parents came from different habitats, I investigated the relative contribution of plasticity and (epi)genetic mechanisms on three behaviours (boldness, activity, and sociality). While these behaviours did not differ between juveniles from both populations, correlations of body length with specific behaviours did. (Chapter 2) • During fieldwork on the Scottish island of North Uist, seven populations of wild three-spined stickleback were surveyed for boldness, exploratory behaviour, and activity. Furthermore, the defensive morphology of these fish was quantified following an armour-staining protocol. Bold fish were found to be less armoured, directly contradicting the phenotypic compensation hypothesis, while more active fish were more armoured, which contradicts the idea that armour is energetically costly. (Chapter 3) • Spurred on by the findings on morphology-behaviour correlations, the ecology of the studied populations was assessed with a focus on parasitism by three common macro-parasites of three-spined stickleback, predation by trout, competition with the nine-spined stickleback, and the availability of resources. I found that all these factors, to some extent, influence individual behavioural variation. Importantly, this study provides the first observational evidence that less-explored factors, such as resource availability and interspecific competition, can be highly relevant influences on individual behaviour. (Chapter 4) • Next, a study on the effect of group behavioural composition on group foraging behaviour was done. With the help of a research visit to Aarhus University, similar experiments were performed on stickleback and social spiders (Stegodyphus dumicola). Group behavioural composition had a strong effect in both study systems, but experience was a more relevant influence on group foraging behaviour in stickleback. By using two different study organisms from quite disparate animal taxa, this allows me to develop hypotheses concerning the evolutionary origin and maintenance of individual behavioural variation and its tentative link with sociality. (Chapter 5) • Lastly, the phenomenon of consistent individual variation in behaviour is explored in novel contexts through conceptual essays (Chapter 6). o Do bacteria offer a suitable system to study ‘personality’? o How can animal personality be leveraged to improve animal welfare? o Are non-antagonistic interspecific interactions an overlooked yet important factor in the study of animal personality?
APA, Harvard, Vancouver, ISO, and other styles
19

Warren, Janice H. (Janice Helene). "Behavioural ecology of crabs in temperate mangrove swamps." Thesis, The University of Sydney, 1987. https://hdl.handle.net/2123/26768.

Full text
Abstract:
Patterns of distribution of crabs inhabiting burrows in three temperate mangrove swamps near Sydney, New South Wales, were described. Heloeoius cordiformis (an ocypodid) did not exhibit a consistent pattern of distribution among three tidal zones, but was always associated with well— drained mounds of substratum within zones. Paragrapsus laevis (a grapsid) tended to be most abundant in the lower two zones on the shore and usually inhabited burrows in the moist or submerged flats between mounds. Sesarma erythrodactyla (a grapsid) was distributed fairly evenly among the three tidal zones and also between mounds and flats. H. cordiformis hibernated in burrows from June through August or September. Overall abundances also varied seasonally, but trends were inconsistent among the three swamps sampled.
APA, Harvard, Vancouver, ISO, and other styles
20

Vanning, Keith. "The thermophysiological ecology of the adder, Vipera berus." Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238293.

Full text
APA, Harvard, Vancouver, ISO, and other styles
21

Buttery, Neil J. "The behavioural and evolutionary ecology of social behaviour in the social amoeba Dictyostelium discoideum." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/the-behavioural-and-evolutionary-ecology-of-social-behaviour-in-the-social-amoeba-dictyostelium-discoideum(4502357b-7087-4568-9014-387776942e1a).html.

Full text
Abstract:
The maintenance of cooperation and altruism in the face of manipulation by exploitative cheaters that reap the benefits of cooperative acts without paying the associated costs is a conundrum in evolutionary biology. Cheaters should spread through a population causing it to crash, yet cooperation is common. There are many models and theories that attempt to explain this apparent contradiction. The social amoeba Dictyostelium discoideum, like many microbial species has been used as a model organism to test these theories and to begin to understand the genetic mechanisms behind social behaviours. The aim of this PhD project is to quantify the interactions that occur between naturally-occurring genotypes during social competition in order to identify the types of cheating behaviours and to understand the evolutionary consequences of such behaviours. I first demonstrate that there is a social hierarchy of genotypes and that cheaters can increase their own fitness by increasing their own spore allocation or decreasing their partner's allocation the precise nature of which is dependent upon unique interactions between each competing pair. I also show that the outcome of social competition is dependent upon the physical environment where it can be significantly reduced, or even avoided by segregation of genotypes during development. Finally, it is demonstrated in a collaborative project that much of the observed social behaviour can be explained in terms of the production of and response to developmental signals.
APA, Harvard, Vancouver, ISO, and other styles
22

Ha, Thang Long. "Behavioural ecology of grey-shanked douc monkeys in Vietnam." Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/252209.

Full text
Abstract:
The grey-shanked douc monkey (Pygathrix cinerea) is an endemic primate to Vietnam found in 1997. The species is critically endangered with less than 1,000 individuals left in the wild. Research was conducted in Kon Ka Kinh National Park, Gia Lai Province Vietnam for 18 months. The monkeys were found in two forest types: (1) closed evergreen lower montane moist sub-tropical forest; (2) mixed broad-leaf and needle-leaf lower montane moist sub-tropical forest. Group size varied from 2 to 88 individuals; average group size was 14.8 individuals.  There were four different social structures found in the encountered groups, including one-male unit (OMU), all-male unit (AMU), multi-male and multi-female group, and solitary group. Annual activity budget involved the monkeys spending the highest proportion of time resting (37.0%) and lowest feeding (11.9%). Seasonality significantly influenced the activity budget result, with increased resting and socialising in the wet season and decreased feeding and travelling. The emergent canopy layer and the main canopy layer in the forest are important for all activities. Trees in the height classes 15-19.9m were very important to the monkeys, since they involved more than 60% of feeding. Branches and boughs were used more often for resting and socialising, while twigs were used more often for feeding and travelling. The monkeys ate 49.5% young leaves, 21.9% ripe fruits, 19.1% unripe fruits and only 9.3% mature leaves. 166 plant species of 40 plant families were identified as foods of the monkeys. The monkeys ate mostly young leaves in the dry season (82%), but switched to fruits (~70%) in the wet season.
APA, Harvard, Vancouver, ISO, and other styles
23

Hughes, David. "The behavioural ecology of strepsipteran parasites of Polistes wasps." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275473.

Full text
APA, Harvard, Vancouver, ISO, and other styles
24

Blandford, P. R. S. "Behavioural ecology of the polecat Mustela putorius in Wales." Thesis, University of Exeter, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377310.

Full text
APA, Harvard, Vancouver, ISO, and other styles
25

Spottiswoode, Claire N. "Behavioural ecology and tropical life-histories in African birds." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615302.

Full text
APA, Harvard, Vancouver, ISO, and other styles
26

Hoelzel, A. Rus. "Behavioural ecology and population genetics of the killer whale." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235855.

Full text
Abstract:
Field observations were collected to assess the social behaviour and foraging strategies of free-ranging killer whales from the eastern North Pacific (near Vancouver Island, Canada) and the western South Atlantic (near Peninsula Valdez, Argentina). The Vancouver Island study concentrated on the environmental correlates of group size and the behavioural dynamics of social groups. There were no correlations between foraging behaviour and small-scale habitat use, however both group size and the spatial distribution of groups were correlated with foraging behaviour. In Argentina the subject whales intentionally stranded to capture pup sea lions. It was possible to observe details of prey choice and foraging strategy. Three social groups were observed in the study area. Area use suggested that the different groups were employing different strategies. Whales within social groups shared prey, but one group would exclude another from the best hunting areas. Whales invested the greatest effort in the area of highest yield, and on the prey-type that required the least effort to catch. Energetic calculations suggested that the rate at which these whales captured sea lion prey was just sufficient to sustain them. Two genetic components, the hypervariable 'minisatellite' loci, and the mitochondrial genome were investigated for each study population. In addition, further samples from Iceland and other populations near the sites at Peninsula Valdez and Vancouver Island were analysed. Whales within social groups at Peninsula Valdez were more closely related than between social groups. In general, whales within local populations had very high levels of genetic similarity compared to between population comparisons. This implies inbreeding within and genetic isolation between populations. Two genetically isolated populations (both near Vancouver Island) were sympatric, and the degree of genetic isolation was equal to the level seen for comparisons between the Atlantic and Pacific. A hypothesis is presented on the role of resource exploitation in the structuring of social groups, and the consequences for the genetic structuring of populations.
APA, Harvard, Vancouver, ISO, and other styles
27

Tkaczynski, Patrick. "The behavioural ecology of personality in wild Barbary macaques." Thesis, University of Roehampton, 2016. https://pure.roehampton.ac.uk/portal/en/studentthesis/the-behavioural-ecology-of-personality-in-wild-barbary-macaques(023582d2-2214-448c-bf12-c1bef7d5549e).html.

Full text
Abstract:
Personality, that is intra-individual consistency and inter-individual variation in behaviour, is widespread throughout the animal kingdom. This challenges traditional evolutionary assumptions that selection should favour behavioural flexibility, and that variation in behavioural strategies reflects stochastic variation around a single optimal behavioural strategy. Adaptive models to explain personality within the framework of evolutionary and behavioural ecology exist, and are typically empirically explored by identifying proximate associations to, and the functional consequences of, personality expression. To date, such studies have typically quantified a narrow range of personality traits within a species, and focused on captive populations or species with relatively limited behavioural or social repertoires. In this thesis, personality is studied in wild Barbary macaques (Macaca sylvanus). Quantification of personality structure in the species was conducted using a multi-method approach, and subsequently, it was examined whether physiological stress response (a proximate association) was related to personality expression, and whether personality expression affected social (functional) outcomes for individuals. Seven personality constructs were identified in Barbary macaques. Three personality constructs were related to physiological stress responses (Excitability, Tactility and Exploration), with the relationship between stress and personality expression dependent on sex, and in some cases rank or age. Two personality constructs (Excitability and Exploration) were associated with measures of social integration. Subjects generally socially assorted themselves according to personality, tending to be in proximity to individuals with a similar personality to themselves. This study contributes methodologically by demonstrating the plausibility of multi-method approaches to measuring personality in wild primates, and empirically, by generating evidence supporting adaptive models for the evolution of personality, namely that intra-individual consistency in behaviour may be mediated by physiology and that inter-individual variation in behaviour has functional benefits in the formation of social relationships and social structures.
APA, Harvard, Vancouver, ISO, and other styles
28

Christian, Sean Francis. "The behavioural ecology of the Eurasian badger (Meles meles) : space use, territoriality and social behaviour." Thesis, University of Sussex, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357263.

Full text
APA, Harvard, Vancouver, ISO, and other styles
29

Loveridge, Andrew John. "Behavioural-ecology and rabies transmission in sympatric southern African jackals." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325375.

Full text
APA, Harvard, Vancouver, ISO, and other styles
30

Fowler, Andrew. "Behavioural ecology of chimpanzees (Pan troglodytes vellerosus) at Gashaka, Nigeria." Thesis, University College London (University of London), 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439338.

Full text
APA, Harvard, Vancouver, ISO, and other styles
31

Wilson, William L. "Behavioural ecology and population regulation of the woodmouse (Apodemus sylvaticus)." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317534.

Full text
APA, Harvard, Vancouver, ISO, and other styles
32

Lehmann, Hagen. "On the applicability of agent based modelling in behavioural ecology." Thesis, University of Bath, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.506830.

Full text
APA, Harvard, Vancouver, ISO, and other styles
33

Richard, Gaëtan. "Behavioural ecology of fishermen and odontocetes in a depredation context." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS018/document.

Full text
Abstract:
De nombreux prédateurs marins se nourrissent directement des prises des pêcheurs. Ces interactions, définies comme de la déprédation, engendrent des conséquences socio-économiques considérables pour les pêcheurs ainsi que des implications de conservation pour la faune sauvage. D’un côté, la déprédation endommage le matériel et augmente l’effort de pêche pour atteindre les quotas. D’un autre côté, la déprédation augmente le risque de mortalité des prédateurs marins (prise accidentelle ou rétorsion létale par les pécheurs). La pêcherie à la palangre est la plus impactée par la déprédation, principalement par les odontocètes, ce qui incite à trouver des solutions. La majorité des études se concentrant sur la déprédation s’est principalement basée sur des observations en surface, de ce fait la manière dont les prédateurs retirent les poissons sur les lignes reste confuse. Par ailleurs, l’impact de la déprédation sur le comportement des pêcheurs ainsi que les facteurs expliquant leur détectabilité n’ont reçu que peu d’intérêt. L’objectif de cette thèse est donc d’étudier ces problématiques par un suivi acoustique, une utilisation de balises et une approche en écologie comportementale humaine, en se concentrant sur la pêcherie palangrière française ciblant la légine australe (Dissostichus eleginoides) impactée par la déprédation des orques (Orcinus orca) et des cachalots (Physeter macrocephalus). Les capitaines ont été décrits comme recherchant leur ressource selon la théorie de « l’optimal foraging », mais avec des perceptions de la compétition et du succès de pêche qui divergent. Certains capitaines seraient ainsi plus enclins à remonter les palangres au plus proche et à rester sur une zone, même en présence de compétition, augmentant alors le risque d’interaction. L’acoustique des navires a révélé que certaines manoeuvres (marche arrière par exemple) propagent différemment sous l’eau. La manière dont les capitaines manoeuvrent leur palangrier influencerait ainsi leur détectabilité et donc leur risque d’interaction avec les prédateurs. D’autre part, l’utilisation de capteurs sur les palangres et les animaux a révélé que les orques et les cachalots sont capables de déprédater sur les palangres posées sur le fond marin. Ces observations laissent à penser que les odontocètes sont en mesure de localiser l’activité de pêche bien avant la remontée de la ligne, ce qui pourrait être expliqué par une signature acoustique spécifique du déploiement de la ligne. L’ensemble des résultats de cette thèse suggère que la déprédation sur les palangres démersales est très probablement sous-estimée. Cette thèse apporte également des éléments importants pour la lutte contre la déprédation, en montrant la nécessité de protéger les palangres dans l’intégralité du processus de pêche
Many marine predator species feed on fish caught by fishers directly from the fishing gear. Known as depredation this interaction issue has substantial socio-economic consequences for fishermen and conservation implications for the wildlife. Costs for fishers include damages to the fishing gear and increased fishing effort to complete quotas. For marine predators, depredation increases risks of mortality (lethal retaliation from fishers or bycatch on the gear). Longline fisheries are the most impacted worldwide, primarily by odontocetes (toothed whales) depredation, urging the need for mitigation solutions to be developed. Most of studies assessing depredation have primarily relied on surface observation data, thus the way odontocetes interact with longlines underwater remains unclear. Besides, the way fishermen respond to depredation during fishing operations, or can influence their detectability to odontocetes, have been poorly investigated. This thesis therefore aimed at investigating these aspects through a passive acoustic monitoring, bio-logging and human ecology approaches, focusing on the French Patagonian toothfish (Dissostichus eleginoides) longline fisheries impacted by killer whales (Orcinus orca) and sperm whales (Physeter macrocephalus). Firstly, this thesis reveals that captains behave as optimal foragers but with different personal perception of competition and fishing fulfilment. Some captains would thus be more likely to stay within a patch or to haul closest longline even in presence of competition, suggesting these captains would show higher interaction rates. Additionally, the propagation of vessels’ acoustics varied depending on the type of manoeuvre (e.g. going backward vs. forward). The way captains use their vessels to navigate may therefore influence their detectability and so their depredation level. Secondly, loggers deployed on both the longlines (accelerometers) and odontocetes (GPS-TDR) revealed that killer whales and sperm whales are able to depredate on longlines while soaking on the seafloor. These observations suggest, therefore, that odontocetes can localise fishing activity before the hauling, which could be partially explained by specific acoustic signatures recorded during the setting process. Altogether, the results of the thesis suggest that depredation rates on demersal longlines are most likely underestimated. The thesis also brings some important insights for mitigation measures, suggesting that countermeasures should start from setting to hauling
APA, Harvard, Vancouver, ISO, and other styles
34

Ahsan, Md Farid. "Behavioural ecology of the hoolock gibbon (Hylobates hoolock) in Bangladesh." Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/283691.

Full text
APA, Harvard, Vancouver, ISO, and other styles
35

Jenkins, Andrew Robert. "Behavioural ecology of Peregrine and Lanner falcons in South Africa." Doctoral thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/16100.

Full text
Abstract:
Bibliography: p. 88-94.
The Peregrine Falcon Falco peregrinus is a specialized predator of birds. It occurs almost worldwide but is generally uncommon. In many areas, it is sympatric with one of a complex of similar, less specialized, congeneric species (subgenus Hierofalco, the desert falcons). Peregrine density and productivity tend to decrease with latitude, while desert falcons may be most successful in the tropics. This study compares the biology of Peregrines and sympatric Lanner Falcons F. biarmicus in South Africa, and examines the relative influence of resource limitation and interspecific competition with congeners on the natural regulation of Peregrine populations in tropical environments.
APA, Harvard, Vancouver, ISO, and other styles
36

Rovero, Francesco. "Non-invasive techniques for studying behavioural mechanisms and physiological states of marine invertebrates." Thesis, Bangor University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322901.

Full text
APA, Harvard, Vancouver, ISO, and other styles
37

Welham, Robert Kenneth. "Optimal annual routines." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268968.

Full text
APA, Harvard, Vancouver, ISO, and other styles
38

Kelly, Christopher Patrick. "Incubation games." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315906.

Full text
APA, Harvard, Vancouver, ISO, and other styles
39

Leighton, Patrick. "Mongoose predation on sea turtle nests: linking behavioural ecology and conservation." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86646.

Full text
Abstract:
The introduced small Asian mongoose (Herpestes javanicus) is a widespread predator of sea turtle eggs and hatchlings in the Caribbean. I studied the behavioural ecology of mongoose predation on the nests of critically endangered hawksbill sea turtles (Eretmochelys imbricata) in Barbados. Combining short-term field experiments with seven years of hawksbill nesting data, I investigated how mongoose foraging behaviour, antipredator behaviour and landscape use explain the spatial and temporal patterns of sea turtle nest predation. An experiment combining artificial nests and predator tracking revealed a direct relationship between fine-scale variation in mongoose activity and nest predation risk. The combination of mongoose avoidance of open areas and the spatial distribution of hawksbill nests relative to patches of beach vegetation accurately predicted the observed peak in nest predation near the vegetation edge. Egg-burial depth by nesting hawksbills also affected predation risk, but this was primarily due to the increased digging effort required rather than any increase in nest concealment with depth. A second experiment with artificial nests confirmed the causal relationship between burial depth and predation risk and showed that substrate disturbance is a primary cue for nest detection by mongooses. At the landscape scale, mongooses tracked local nest abundance but showed a fine-scale negative response to human beach use, suggesting that human activity on nesting beaches may improve nest survival by deterring predators. Finally, an analysis of nest survival times showed that nests were most vulnerable to predation in first days following oviposition and that predation risk increased over the nesting season, providing a general framework for planning where and when predation reduction methods should be applied. I conclude that predation risk for sea turtle nests is likely to depend on: i) how predator nest-finding behaviour is modulated by nest characteristics s
La petite mangouste indienne (Herpestes javanicus) est une espèce introduite dans de nombreuses îles des Caraïbes et est un prédateur important des oeufs de tortues marines. J'ai étudié l'écologie comportementale de la prédation par les mangoustes sur les nids de tortue imbriquée (Eretmochelys imbricata), une espèce en danger critique d'extinction, à la Barbade. En combinant des études expérimentales de courte durée avec des données de prédation des nids de tortues imbriquées s'échelonnant sur sept années, j'ai investigué comment le comportement d'approvisionnement, le comportement anti-prédateur, et l'utilisation du paysage par les mangoustes expliquent les patrons spatiaux et temporels de la prédation des nids. Une étude expérimentale combinant des nids artificiels et une mesure passive de l'activité des prédateurs a démontré une relation directe entre la variation spatiale de l'activité des mangoustes et le risque de prédation des nids. Conjointement, l'évitement des espaces dépourvus de végétation sur la plage par les mangoustes et la distribution spatiale des nids de tortues imbriquées en fonction de la végétation ont prédit de manière précise le patron de prédation élevé observé dans la zone bordée de végétation. La profondeur des nids affectait également le risque de prédation mais avait peu d'influence sur la détection des nids par les mangoustes. L'effet relié à la profondeur était surtout dû à l'effort d'excavation supplémentaire. Une deuxième étude expérimentale utilisant des nids artificiels a confirmé la relation directe entre la profondeur des nids et la prédation, démontrant que la mangouste utilise la perturbation du sable créée lors de la ponte comme principal indice de détection des nids. A l'échelle du paysage, l'activité des mangoustes suivait la disponibilité des nids de tortues sur la plage. Cependant, il y avait une relation négative entre l'activité des mangoustes et l'u
APA, Harvard, Vancouver, ISO, and other styles
40

Geffen, Eli. "The behavioural ecology of the Blanford's fox, Vulpes cans, in Israel." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257737.

Full text
APA, Harvard, Vancouver, ISO, and other styles
41

Thom, Michael. "The mating system and behavioural ecology of American mink (Mustela vison)." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249283.

Full text
APA, Harvard, Vancouver, ISO, and other styles
42

Bartlett, Jonathan. "The behavioural ecology of the burying beetle Nicrophorus vespilloides (Coleoptera: Silphidae)." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/16940.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Richards, Elizabeth Loys. "Foraging, personality and parasites : investigations into the behavioural ecology of fishes." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55475/.

Full text
Abstract:
This thesis investigated differences in foraging behaviour, personality and parasitic infection, using behaviour experiments, traditional parasitology and molecular ecology. Five fish species, and a directly-transmitted ectoparasite, were used as model organisms. Evidence for a conservative foraging strategy was found in the four tropical fish species (Poecilia reticulata, P. sphenops, Xiphophorus maculates, X. hellerii) and in a temperate species (Gasterosteus aculeatus). In the latter, this behaviour was unaffected by social context, with no significant differences between isolated fish and shoals. Also, guppies showed a reduced acceptance of novel, conspicuously-coloured prey. Furthermore, using molecular scatology techniques, both prey and host species-specific DNA were detected in fish faecal samples so this methodology can be used in the future to examine diet in the wild. When considering the personality trait, boldness, guppies from two wild populations differed significantly in their relative boldness, but individuals within a single population were similar in their relative boldness. Boldness of fish was affected by mating, with virgin and pregnant females being bolder than their mated counterparts. Also, boldness impacted on shoaling behaviour, shy fish formed larger and tighter shoals than bold conspecifics. This had consequences for parasite transmission, with shy fish having higher parasite loads and a greater change in parasite load across an infection period than their bold counterparts. Furthermore, host contact was the main factor influencing transmission of a directly-transmitted ectoparasite within a group-living host species. Significantly more parasites were transmitted between hosts when hosts had more frequent and more prolonged contact with each other. Clearly, monitoring individual differences in various aspects of an animal's behaviour can answer many questions of ecological relevance, as well as discovering the evolutionary origins of such individual behavioural traits.
APA, Harvard, Vancouver, ISO, and other styles
44

Morrogh-Bernard, Helen Celia Christopher. "Orang-utan behavioural ecology in the Sabangau pear-swamp forest, Borneo." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611376.

Full text
APA, Harvard, Vancouver, ISO, and other styles
45

Parish, David M. B. "Behavioural ecology of the lapwing Vanellus vanellus L. in Upper Teesdale." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5382/.

Full text
Abstract:
From 1993-95, the behavioural ecology of the lapwing Vanellus vanellus L. was studied in Upper Teesdale, Co. Durham, with the aim of describing the behavioural mechanisms underlying some population characteristics. Significant effects of age and individuals were found in many aspects of Lapwing breeding biology. Older Lapwings returned to the breeding grounds before yearlings, with adult males returning earliest of all. First breeding attempts occurred at one-year-old for most females, but at two-years-old for most males. Males two-years-old and over showed a remarkable degree of consistency in breeding status (breeding or non-breeding) in consecutive years, even where this meant persistent non-breeding. The age of first breeding, and consistency of breeding status among males, indicates intense intermale competition for limited breeding habitat, with some males, perhaps of low quality, apparently permanently prevented from breeding. However, few differences in annual breeding success were found among females of different ages. With the exception of egg size in first clutches, where yearling females laid eggs around 5% smaller than adults, yearling and adult females were similarly fecund. Laying dates and egg volumes in first clutches exhibited high indices of repeatability between years, probably reflecting a high degree of heritability of these traits. High frequencies of polygyny were recorded, despite the traditional view of strict monogamy for this species. The mating success of male Lapwings increased between one and three years-of-age. The distinct parental roles of the sexes facilitated the occurrence of polygyny by reducing activity-budget costs of polygynous associations for both sexes. Polyterritoriality, polyandry and double-brooding were also recorded and discussed.
APA, Harvard, Vancouver, ISO, and other styles
46

Rowland, Hannah Miriam. "The visual and behavioural ecology of countershading and other prey defences." Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442032.

Full text
APA, Harvard, Vancouver, ISO, and other styles
47

Gammans, Nicola R. "Seed dispersal by ants : behavioural and chemical ecology of a mutualism." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427451.

Full text
APA, Harvard, Vancouver, ISO, and other styles
48

Gauld, Niall Roderick. "The behavioural ecology of migratory salmonids in the River Tweed, UK." Thesis, Durham University, 2014. http://etheses.dur.ac.uk/10722/.

Full text
Abstract:
This study investigated various life history stages of salmonids within the River Tweed, UK with a focus on migratory movements. The River Tweed is a large upland river situated on the border between Scotland and England and is home to some of the healthiest stocks of Atlantic salmon (Salmo salar) and sea trout (Salmo trutta) in the UK. The research undertaken as part of this thesis aims to assess how management can be improved to aid the migration of salmonids moving within freshwater. This is of particular importance due to increased demand for renewable energy including small scale hydropower as well as legislation that demands improved fish passage within rivers such as the Water Framework Directive. Sea trout smolts were captured and acoustic tagged to assess the roles that in river obstructions such as weirs play on their migration between years with varying river flow. The two study years varied radically in flow levels due to the incidences of hydrological drought in 2010 significant differences were observed in the degree of delay smolts experienced at weirs as well as differing responses to flow during years. Sea trout and salmon were acoustic tagged and tracked during their freshwater spawning migration. The aim of the study was to examine the interspecific differences in spawning migration such as spawning location and movement rate during migration. By looking at migration rate of sea trout and salmon it was observed that both species decreased their migratory rate the further into the river system they moved. It was also observed that sea trout and salmon spawned in different locations, with sea trout using tributaries and salmon using lower stretches of the Tweed. The small scale movements of freshwater resident trout was studied. Freshwater resident trout tend to have relatively small home ranges and often hold a territory within their home range. As a result they also tend to rapidly home back to their territory after being displaced from it. As such, the study aimed to assess the degree to which brown trout home after being displaced, particularly whether being offered a choice of empty territories at their site of displacement would affect their homing behaviour. The study found that there was no apparent difference in homing behaviour observed between treatment groups offered empty territories at their site of displacement compared to controls that were displaced into fully populated sites. Continued research into the behaviour of salmonid species is important due to increasing demand on water resources, future conflict between man and fishes water needs is inevitable.
APA, Harvard, Vancouver, ISO, and other styles
49

Gennari, Enrico. "Thermal physiology and behavioural ecology of the white shark, carcharodon carcharias." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/64002.

Full text
APA, Harvard, Vancouver, ISO, and other styles
50

Du, Plessis Morne Andre. "Behavioural ecology of the Redbilled Woodhoopoe Phoeniculus purpureus in South Africa." Doctoral thesis, University of Cape Town, 1989. http://hdl.handle.net/11427/6252.

Full text
Abstract:
Includes bibliographies.
A study was made of two Redbilled (Green) Woodhoopoe Phoeniculus purpureus populations spanning an eight year period (1981-1988) and 258 'flock-years', in the eastern Cape Province of South Mrica. The main objectives of the study were to investigate (1) why woodhoopoes live in groups; (2) why nonbreeders do not breed; and, (3) why nonbreeders provision young that are not their own? Ecological and demographic data were gathered in addition to detailed behavioural observations of 54 woodhoopoe flocks. The following experimental manipulations were performed: (1) breeders were removed from flocks to (a) monitor dispersal patterns and restructuring of flocks; and, (b) observe behavioural reactions by remaining birds; (2) cavity availability was (a) decreased, to enable quantification of availability; and, (b) increased, by addition of nest/roost boxes to an area which supported no permanent woodhoopoe territories; and, (3) stimuli, associated with the food provisioning response of adult birds, were manipulated to investigate the evolutionary basis of allofeeding behaviour Variability in social and reproductive behaviour reflects environmental selection pressures, in the form of roost-cavity availability, with a reduction in cavity availability leading to increased group size. The group-territorial social system and high level of inbreeding of Redbilled Woodhoopoes have evolved primarily in response to environmental constraints on dispersal, rather than by particular benefits that arise from group living. Therefore, the habitat-saturation hypothesis best explains group living of woodhoopoes. Behavioural dominance hierarchies ensure that dominance relationships are well-defined among potential competitors (for breeding status), and thereby minimize disruption to flock cohesion upon the death (or removal) of a breeder. If competition for a breeding vacancy arose at the time of the breeder's death, the resultant delay in occupancy of the breeding vacancy would increase the likelihood of competition from unrelated birds. The establishment of such hierarchies is therefore adaptive in the context of the direct component of kin selection. The presence of nonbreeding helpers do not increase fledgling success, breeding frequency, survivorship (of any age, sex or social class), or number of breeder-offspring produced. Because no unambiguous indirect fitness benefits could be shown to result from helping behaviour (specifically allofeeding), I propose that the unselected (misdirected parental care) hypothesis is a viable alternative to the 'functional hypotheses.' This hypothesis is supported by observations/manipulations of misdirected food provisioning by both breeders and helpers.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography