Rozprawy doktorskie na temat „Ecology, Behaviour and Conservation”

Abstract The effects of habitat loss and fragmentation on the genetic structure and vulnerability of populations strongly depend on the behaviour of a particular species. In this thesis, I examined the effects of forest fragmentation on genetic population structure with the aim of identifying and evaluating the different genetic and behavioural factors important for species conservation and management on different geographical scales. The species studied were the mound building red wood ants Formica lugubris and F. aquilonia, and a lekking bird, the capercaillie, Tetrao urogallus. Habitat loss and fragmentation affected the genetic structure in both wood ants and capercaillie. In general, the effects were related to the time since fragmentation and to the level of habitat loss and isolation from the other existing populations. The loss of genetic diversity due to population fragmentation was less observable than the differences in population structure. The response to habitat fragmentation was further dependent on species characteristics such as dispersal and mating behaviour. Sociality affected the genetic vulnerability of wood ant populations by decreasing gene diversity, increasing inbreeding depression and restricting gene flow between subpopulations. The results on the capercaillie in turn suggested that lekking behaviour restricts dispersal of both sexes, thus elevating the occurrence of inbreeding between individuals. The present study provided important information on species conservation and management in terms of better understanding species' biology and behaviour, as well as increased knowledge concerning the genetic issues that should be taken into account when planning conservation actions. By examining the genetic structure of the species it was possible to clarify the conservation status including the effective population size, the question of origin, and the genetic vulnerability (genetic diversity, inbreeding and inbreeding depression) of the populations and/or species. Overall, the results emphasised the importance of preserving the effective population size and the connectivity of habitat patches when planning species specific management strategies. There were great differences in conservation needs among the species, which should be taken into account especially in local management actions.

Determining the dynamic nature of animal movement has been an important component in a wider understanding of animal population ecology. Generally, this is because temporal change in the density of a population at a specific geographic location is not only a function of births and deaths but also of movements, including migration. The increased availability of remote telemetry and biologging systems in recent years has enabled many studies tracking marine predators, such as turtles, seabirds and marine mammals, but a general understanding of spatial dynamics in large sharks remains less well developed. This is in part due to few studies having achieved sufficiently long-term, multi-year tracks to detect changes in movement behaviour over time. Determining the timing, repeatability and potential motivations for movements of large sharks is necessary to understand the ecological and evolutionary role of such behaviour more generally in marine predators. Furthermore, given global concerns of declining shark populations, a detailed appreciation of shark movements can reveal the extent 6 of overlap with area-focused human activities (e.g. fishing), as well as inform assessments of population trends and spatial management options. In order to demonstrate how shark migratory behaviour and spatial dynamics can vary dramatically depending on the species and location, with subsequent contrasting conservation implications, the present work used longterm, remote telemetry to reveal detailed patterns in shark movement behaviour at two very different geographical scales: broad-scale movements of larger species that encompass ocean basins, versus fine-scale movements of reef-associated species at a remote atoll. First, using satellite telemetry, it was revealed for the tiger shark Galeocerdo cuvier, that adult males undertake annually repeated, roundtrip migrations of over 7,500 km in the northwest Atlantic. Second, acoustic telemetry was used to determine the fine-scale spatial dynamics of a multispecies shark assemblage at a small, remote atoll in the Seychelles, Indian Ocean, where a number of species displayed perennial residency. While the fine-scale movements of reef sharks in the Seychelles suggest an MPA of moderate size may be an effective management option, the long-distance migrations of the tiger sharks in the Atlantic reveal that conservation efforts targeting them must account for dynamic fisheries interactions over large geographical scales, potentially requiring time-area closures to be effective. Examining the long-term movement behaviour of different shark species over contrasting geographical scales has emphasised the importance of understanding spatial dynamics when informing management decisions, and has contributed to a wider understanding of the population ecology of these species.

Two of the three turtle species inhabiting the Murray River, Emydura macquarii and Chelodina longicollis, have declined since the 1970s, whilst C. expansa is rare. As much of the ecology of these turtles and their threats are poorly understood, a comprehensive conservation plan is yet to be drafted. Here, I describe a threat to turtles, investigate aspects of their ecology and behaviour, and evaluate methods for public engagement in turtle conservation. These areas are critical for the design of an effective management plan. In Chapter 2, I describe mortality on roads using data collected via citizen science, and show that C. longicollis is most at risk on multiple-lane highways during their nesting season and after rain. I propose testing road signs, eco-passages and artificial nesting grounds to address this issue. In Chapter 3, I evaluate the consequences of the decline of all three species by quantifying their scavenging role, and show that they are key scavengers that positively affect water quality. Hence, areas with few or no turtles are likely to be most affected by unchecked carrion decay, highlighting the need to address the turtle decline. Headstarting hatchlings may be an effective conservation technique. In Chapter 4, I test whether hatchling E. macquarii associate with aquatic vegetation, and whether captivity affects their behaviour and short-term survival, to inform a headstarting plan. I conclude that E. macquarii hatchlings should be released at hatching in areas with abundant aquatic vegetation. In Chapter 5, I show that skills and knowledge gains after participating in the citizen science project TurtleSAT are associated with behavioural and attitudinal changes that may be beneficial for turtle conservation. This thesis justifies the conservation of the turtles of the Murray River, informs a future conservation plan, and provides an example approach for other poorly known species that are likely to play key roles in their ecosystem functioning.

Biological invasions threaten biodiversity globally, and degraded ecosystems increase the potential for invaders to compete with threatened native populations. In natural systems, niche partitioning minimizes interspecific competition, but introduced species may alter expected outcomes by competing with ecologically similar species for scarce resources. Where food production is highly variable, coexistence of native and invasive competitors may depend on dietary niche flexibility. Territorial species under invasion face additional challenges to maintain economically defendable territories. From 2011-2016, we conducted removal and behavior experiments to determine effects of non-territorial introduced Abert’s squirrels (Sciurus aberti) on diet, space use, and territoriality of endangered Mount Graham red squirrels (MGRS; Tamiasciurus fremonti grahamensis) in their declining habitat in the Pinaleño Mountains, Arizona. We collected comparative data from Arizona sites of natural syntopy between Abert’s and Fremont’s squirrels (T. fremonti). Stable isotope analysis revealed similar dietary partitioning among populations. Experimental removals did not appear to affect MGRS diet. Space use by MGRS responded inconsistently to removals; territory sizes increased after the first removal, but did not change following the second removal. Territory sizes and body mass of MGRS were sensitive to conspecific population density and food production. Behavioral experiments showed MGRS were more aggressive than other Fremont’s squirrels (hereafter, red squirrels). Dietary flexibility of Abert’s squirrels may have facilitated coexistence with MGRS, possibly due to coevolved resource partitioning with red squirrels. However, aggressive territoriality toward Abert’s squirrels may incur fitness costs for MGRS especially during poor food production years. Climate change may reduce the advantage of ecological specialist species globally, and where introduced species are better-adapted to novel environmental conditions, native species may ultimately be replaced.

In the tradition of previous studies of threatened species, this thesis was undertaken with the aim of improving our understanding of the ecology of the White-winged Nightjar Caprimulgus candicans, and providing the information necessary to facilitate conservation efforts on its behalf. In 1998-2001, I studied a population of White-winged Nightjars at Aguará Ñu, an area of cerrado habitats within the Reserva Natural del Bosque Mbaracayù, eastern Paraguay. Over the course of three fieldwork seasons, I captured and ringed a total of 49 nightjars (34 adults and 15 young birds). Young females first bred at approximately one year old, while still in pre-definitive plumage. Young males exhibited a form of delayed plumage maturation, whereby they only attained definitive plumage following a prolonged moult spanning much of their first potential breeding season. No evidence was obtained to suggest that they succeeded in breeding while in this conspicuously intermediate state of moult. Considerable variation was noted in the plumage whiteness of definitive males, but no clear evidence was found for consistent age-related increases in white. During the breeding season, males defended small aggregated display territories, at which they conducted nuptial display flights between late August and early January. Female nightjars were responsible for all the parental care, and apparently visited male display arenas solely to obtain copulations. Chick paternity data confirmed that the study population was polygynous, with patterns of male aggregation suggestive of an exploded lek or 'landmark' mating system. Radio-telemetry studies showed that nightjars utilised home ranges of at least 20 to 40 hectares during the eight to ten months for which they were monitored. Home ranges contained a disproportionately large amount of young campo cerrado vegetation, but no forest or old campo cerrado habitats. When selecting foraging sites within their ranges, nightjars preferred younger and avoided older campo cerrado vegetation; wet grassland was utilised roughly in proportion to its availability. Observed patterns of habitat selection were potentially explained by the greater abundance of insect prey in younger habitats. When selecting daytime roost sites, nightjars preferred vegetation of intermediate age, reflecting their need for a balance between cover and ease of access. A more general analysis of patterns of sexual dimorphism within the Caprimulgidae showed that, although almost 80% of nightjar species exhibit some dimorphism of plumage whiteness, the study species was by far the most extreme case. The striking plumage of the male was partly explained by a strong positive relationship between wing white and openness of breeding habitats within the family. However, this failed to explain the complete absence of white in the female plumage, or the extent of white dimorphism shown by the species. The most likely explanation would appear to be that extreme plumage dimorphism occurred in conjunction with the evolution of polygyny and female-only care in this open-country species. The implications of these findings for the conservation of the White-winged Nightjar are highlighted, and recommendations are proposed for future work and conservation action.

Ett stort antal utrotningshotade djurarter ingår idag i bevarandeprogram världen över. Små populationer hålls då i skyddade miljöer, exempelvis i djurparker, och i många fall är målet att återintroducera djur till naturen. Dessvärre är det vanligt att det uppstår problem när djur återintroduceras vilket kan bero på beteendemässiga anpassningar som uppkommit under tiden i fångenskap. Syftet med den här studien var därför att undersöka beteendemässiga aspekter på bevarandeavel och försöka ta reda på om och hur djur påverkas beteendemässigt av att hållas i skyddade fångenskapsmiljöer. I projektet användes röda djungelhöns (Gallus gallus) som en fallstudie. En granskning av beteendevariation mellan olika populationer av röda djungelhöns i fångenskap konstaterade skillnader i antipredatorbeteende, socialt beteende och födosöksbeteende. Vid en genetisk studie av samma populationer upptäcktes dessutom ett samband mellan genetisk diversitet och beteendevariation som potentiellt kan vara intressant ur ett bevarandeperspektiv. Socialt beteende, födosöksbeteende och olika aspekter av rädsla studerades vidare i populationer med olika bakgrund som fick växa upp tillsammans i en grupp. Resultaten visade att populationerna bara skilde sig åt i rädslebeteenden vilket antyder att denna typ av beteende i större utsträckning påverkas av långvarig avel i en viss fångenskapsmiljö medan socialt beteende och födosöksbeteende istället kan bero på den omedelbara sociala eller fysiska miljön. Antipredatorbeteende studerades också i en longitudinell studie av två populationer över fyra generationer och det visade sig att populationerna blev mer lika varandra ju längre tiden gick då de hölls under likadana miljöförhållanden. Det verkar alltså som om antipredatorbeteende kan förändras av avel i en viss miljö efter bara ett fåtal generationer. Utöver detta studerades även dagliga beteendemönster i olika djurparksmiljöer samt dygnsrytm av galanden hos både vilda populationer och djurparkspopulationer inom artens naturliga utbredningsområde. Resultaten tyder på att sådana beteendemönster inte påverkas nämnvärt av att djur hålls i fångenskap. Fallstudien som presenteras här är ett av de första försöken att, ur ett bevarandeperspektiv, studera hur fångenskapsmiljöer kan påverka djurs beteende och resultaten talar för att dessa aspekter är viktiga att ta hänsyn till vid planering av bevarandeavel.
A number of endangered species are currently involved in conservation breeding programs worldwide. Conservation breeding deals with propagation of captive populations, often with the ultimate aim of releasing animals into the wild. However, an alarmingly high proportion of reintroductions have not been successful in establishing viable populations, possibly due to behavioural problems caused by genetic adaptation to captivity. The main aim of this thesis was to study behavioural aspects of conservation breeding and investigate whether, and how, maintenance of small populations in captivity cause behavioural modifications, which could affect the success of reintroductions. Throughout the project, the red junglefowl (Gallus gallus) was used as a case study, representing animals maintained in captive populations. A screening of behavioural variation revealed that captive populations differ in antipredator, social and exploratory behaviours, all of which are central components of life in the wild. A correlation was also found between genetic diversity and behavioural variation. This has not been reported before and may potentially have interesting implications for conservation breeding. When studying the behaviour of populations with different backgrounds being raised together as one group, the results suggested that fear-related behaviours may be more affected by long-term breeding in a certain captive environment than social and exploratory behaviours which seem to be more influenced by the immediate social or physical environment. A longitudinal study of antipredator behaviour in two populations across four generations revealed that the populations became more similar over time when maintained under identical conditions. This demonstrates that effects of a new environment can appear after only a few generations. Furthermore, daily behavioural routines in different captive environments as well as diurnal crowing rhythms in both wild and captive populations were studied in the species’ natural region of distribution and the results suggest that such behavioural patterns are not affected by the captive environments to any notable extent. The present case study is one of the first attempts to, from a conservation perspective, study how captive environments can affect behaviour and the results imply that these aspects are important to take into consideration in conservation breeding programs.

Current habitat-association models used in the management of the socio-economically and ecologically important chalk stream salmonid populations fail to incorporate fish behaviour and the interactions between fish with their environment and this limits their ability predicting management-relevant salmonid population responses to environmental change. A salmonid individual-based model is parameterised to predict fish distributions and growth as the modelling approach address the weaknesses of current models. Virtual forager parameters are derived from published investigations and models of salmonid behaviour and bioenergetics. Data from three field studies at the same chalk stream site are used to describe the environment and initial fish population with subsequent data on fish population patterns used to statistically validate the IBM. I found that current recommendations for population enhancement may be futile beyond a threshold population density and regimes that address habitat quality should be adopted. Potential parasite impacts are investigated theoretically by simulations on the mode of impact on their host and identify the most population damaging parasites as those with high effect on host physiology. The management of salmonid predators in fisheries is predicted to have little benefit to salmonid growth and should not be implemented. Additionally, the removal of the dominant aquatic macrophyte for flood risk management is potentially damaging to salmonid populations and recommendations for a sympathetic design are provided. The model described here can be used to produce robust predictions of salmonid population patterns in riverine habitat and allows users to test the impact of environmental change on salmonids to be used for proactive management in light of current rates of environmental change.

L'étude de l'écologie des cétacés vivant sous la pression d'activités anthropiques est essentielle pour leur conservation. Cependant, il existe peu d'informations sur les cétacés et la conchyliculture. À l'aide d'un ensemble de données collectées à long terme, cette étude examine l'écologie et le comportement d'un cétacé côtier, le grand dauphin (Tursiops truncatus), vivant dans une zone importante pour la conchyliculture (Ría d’Arousa, Nord-Ouest de l'Espagne). Le grand dauphin était présent à l'année dans cette région. Leur abondance saisonnière variait de 56 à 144 individus et leur survie apparente était élevée. Parmi les facteurs environnementaux étudiés, la profondeur et la présence de fermes conchylicoles influaient sur leur utilisation de l’habitat, et la chlorophylle-a et l’oxygène dissous influaient sur leurs modes d’agrégation spatio-temporelle. Leur comportement alimentaire dépendait principalement de la température de la surface de la mer, de l’heure de la journée et du fait que les dauphins s’alimentent dans les zones conchylicoles, les dauphins ayant une probabilité plus élevée de se nourrir à l'intérieur de ces zones, qu'à l'extérieur (57%-43%). Certains individus s’alimentaient plus fréquemment que d'autres autour des fermes conchylicoles. À leur tour, les individus qui se nourrissaient fréquemment autour des fermes avaient des associations plus faibles que les autres. Cette étude génère des informations clés sur l'écologie et le comportement d'un cétacé vivant sous la pression de l'industrie conchylicole, sur les priorités de conservation des cétacés vivant sous de telles pressions, ainsi que sur les réglementations applicables au secteur de la conchyliculture
Studying the ecology of cetaceans living under the pressure of anthropogenic activities is essential for their conservation. Yet, there is a paucity of information on cetaceans and shellfish farming. Using a long-term and year-round dataset, this study investigates the ecology and the behaviour of a coastal cetacean, the bottlenose dolphin (Tursiops truncatus), in an important area for shellfish farming (Ría de Arousa, North-West Spain). A resident population of bottlenose dolphins was present year-round in this area. Their seasonal abundance varied from 56 to 144 individuals and their apparent survival was high. Of the investigated environmental factors, depth and shellfish farms were influencing dolphins habitat use, and chlorophyll-a and dissolved oxygen were influencing their spatio-temporal aggregation patterns. Foraging behaviour was mainly determined by the sea surface temperature, time of the day, and whether the dolphins were foraging within shellfish farm areas. Dolphins were predicted to be more likely found foraging inside these areas than outside (57% vs. 43%). Findings of this study also revealed variation in foraging behaviour among dolphins, with some individuals foraging more frequently than others within the shellfish farms. In turn, individuals that frequently foraged within shellfish farms had weaker associations compared to others. This study generates key insights into the ecology and the behaviour of a coastal cetacean living under the pressure of the shellfish farming industry. It further provides valuable information on conservation priorities for coastal cetaceans living under such pressures as well as regulations for the shellfish farming industry

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

Thesis (MScConsEcol) -- Stellenbosch University, 2003.
ENGLISH ABSTRACT: This thesis describes the findings of a survey to investigate the attitudes and behaviour of private landholders towards the conservation of Overberg Coastal Renosterveld, a highly endangered grassy-shrubland of the Cape Floral Region (CFR) lowlands, now 94% transformed. Personal interviews were conducted with 36 farmers in the Overberg region of the Western Cape, by administering a questionnaire. The following aspects were quantitatively described using the Statistical Package for Social Scientists (SPSS): Renosterveld management and utilisation behaviour, perceived value of Overberg Coastal Renosterveld; landholder knowledge of its conservation importance and willingness to conserve it. Attitudes towards incentives for conservation; conservancies; and the provincial conservation authorities were also investigated. Willingness to conserve was explored further using SPSS cross-tabulation analyses. It was found that farmers who were more willing to conserve were younger, did not necessarily have a better education, and owned larger farms (> 500 ha) with a greater amount of remnant renosterveld (> 300 ha) than farmers less willing to conserve. Attitudes towards Overberg Coastal Renosterveld were largely negative, due to certain associated plants and animals which are problems for farmers, and because it is not economically advantageous to retain it. However, provision of incentives (of which assistance with fencing and land management was most attractive) and increased extension support will provide practical positive inducements for conservation. There is also a need for more landholder education regarding the scarcity of coastal renosterveld to prevent transformation of remaining fragments. The second component of the study aimed to construct a user-friendly index to measure the conservation attitudes of landholders towards conserving Overberg Coastal Renosterveld. An interative item analysis was executed on the data, using Spearman Rank Order correlations and Cronbach's Alpha. Results yielded an index with two dimensions and a Cronbach Alpha co-efficient of 0.67. The dimensions or components of conservation attitude towards renosterveld included: (i) a landholders' perception of the perceived benefit of Overberg Coastal Renosterveld; and (ii) their willingness to conserve it. The mean conservation attitude score was 0.6 (± 0.03), indicating that landholder attitudes were generally sympathetic towards renosterveld conservation. This suggests that while many landholders do not place a high value on Overberg Coastal Renosterveld due to its low agricultural value, their willingness to conserve it is in some cases higher than expected, which possibly explains the above-average mean conservation attitude score. An analysis of variance showed that the following variables were significantly, positively correlated with conservation attitude: (i) area of Overberg Coastal Renosterveld; (ii) landholder environmental group membership status; (iii) presence of ecotourism activities on the property; and (iv) how long the property had been in the owner's family. The intended application of the index is that index scores (amenable for use in a Geographical Information System database) can assist conservation practitioners in deciding where resources should be allocated, on the assumption that high-scoring individuals are more likely to want to take part in conservation initiatives.
AFRIKAANSE OPSOMMING: Hierdie proefskrif beskryf die bevindings van 'n opname waarin die houdings en gedrag van private grondeienaars ten opsigte van Overberg Kustelike Renosterveld ondersoek word. Altesaam 94% van die oorspronklike renosterveld, 'n hoogs bedreigde, grasagtige struikveld in die laaglande van die Kaapse Planteryk (KPR) , is reeds getransformeer en verander. Persoonlike onderhoude is met 36 boere in die Overbergstreek van die Wes-Kaap gevoer en 'n vraelys is aan hulle gestel. Die "Statistical Package for Social Scientists" (SPSS) is gebruik om die volgende aspekte kwantitatief te beskryf: die bestuur en benutting van Overberg Kustelike Renosterveld; die waarde wat toegeskryf word aan hierdie renosterveld; asook grondeienaars se kennis oor die bewaringsbelang van Overberg Kustelike Renosterveld en hul bereidwilligheid om dit te bewaar. Houdings jeens aansporingsmiddele om bewaring te bevorder, bewareas en die provinsiale bewaringsowerhede is ook ondersoek. Private grondeienaars se bereidwilligheid om betrokke te raak by bewaringswerk is verder ondersoek deur gebruik te maak van die SPSS-kruistabelleringsanalise. In vergelyking met boere wat nie bewaring ondersteun nie, is gevind dat die meer bewaringsgesinde boere jonger is, nie noodwendig 'n beter opvoeding het nie, en groter plase (>500 ha) besit waarop meer brokkies oorblywende Overberg Kustelike Renosterveld (>300 ha) gevind word. Grondeienaars se houding jeens Overberg Kustelike Renosterveld was grootliks negatief. Dit is as gevolg van sekere verwante plante en diere wat deur boere as probleme ervaar word, en omdat dit nie ekonomies lewensvatbaar is om renosterveld te behou nie. Die beskikbaarheidstelling van aansporingsmiddele (waarvan hulpverlening met omheinings en grondbestuur die aantreklikste was), en 'n toename in landbou-voorligting is egter praktiese en positiewe dryfvere wat bewaring kan bevorder. Daar is ook 'n behoefte vir meer opvoeding van grondeienaars oor aspekte soos die skaarsheid van Overberg Kustelike Renosterveld, sodat die verdere transformasie van oorblywende fragmente voorkom kan word. Die tweede gedeelte van die studie was daarop gemik om 'n gebruikersvriendelike indeks te ontwikkel waarmee die bewaringsgesindheid van grondeienaars teenoor die bewaring van renosterveld gemeet kan word. Deur gebruik te maak van Spearman se rangorde-korrelasies en Cronbach se Alpha is die data aan 'n herhalende item-analise onderwerp. Die resultate het 'n indeks met twee dimensies en 'n Cronbach Alpha-koëffisiënt van 0.67 gelewer. Die dimensies of komponente van bewaringsgesindheid jeens renosterveld het onder meer ingesluit: i) 'n grondeienaar se opvatting oor die moontlike voordeel van Overberg Kustelike Renosterveld en ii) sy/haar bereidwilligheid om dit bewaar. Die gemiddelde telling vir bewaringsgesindheid was 0.6 (± 0.03), wat in die algemeen 'n simpatieke houding jeens die bewaring van Overberg Kustelike Renosterveld onder grondeienaars aandui. Hiervolgens blyk dit dat alhoewel heelwat grondeienaars weens die lae landbouwaarde van renosterveld nie 'n hoë waarde op hierdie plantegroeitipe plaas nie, hulle bereidwilligheid om dit te bewaar soms verwagtinge oortref. Dit is dalk 'n moontlike verklaring vir die bogemiddelde gemiddelde bewaringsgesindheidtelling. 'n Variansie-analise het 'n noemenswaardige, positiewe korrelasie met bewaringsgesindheid ten opsigte van die volgende veranderlikes getoon: i) area van Overberg Kustelike Renosterveld; ii) die grondeienaar se moontlike lidmaatskap van 'n bewaringsgroep; iii) die teenwoordigheid van ekotoerisme-bedrywighede op die eiendom; en iv) die tydperk wat die eiendom al in besit van die grondeienaar se familie is. Die voorgestelde gebruik van die indeks is toepaslik omdat die indeks-tellings (wat vir gebruik in 'n Geografiese Inligtingstelsel databasis aangepas kan word) bewaringslui kan help met besluite random die toekenning van hulpbronne. Die aanname is dat individuele grondeienaars wie hoë tellings aangeteken het, met alle waarskynlikheid meer geredelik aan bewaringsinisiatiewe sal wil deelneem.

Habitat loss and the resulting fragmentation can alter animal movements and disrupt animal seed dispersal mutualisms; however, these effects on spatial patterns of seed dispersal are not well understood. To explore the effects of habitat loss and fragmentation on seed dispersal distances and seed dispersion (aggregation), I created a spatially-explicit, individual-based model of an animal dispersing seeds (SEADS – Spatially-Explicit Animal Dispersal of Seeds). For Chapter 1, I ran SEADS in a theoretical landscape of 0-90% habitat loss to determine the effects of habitat loss on three animal traits relevant to seed dispersal: movement distance, gut retention time, and time between movements. SEADS results revealed a complex interaction involving all animal traits and habitat loss on dispersal distances and dispersion, driven by a novel underlying mechanism of fragment entrapment. Unexpectedly, intermediate habitat loss could increase dispersal distances and dispersion relative to low and high habitat loss for some combinations of animal traits. In Chapter 2, I developed a new method (TriAD) to estimate animal locations from triangulation data to improve triangulations for toucans. Location estimates calculated with TriAD averaged 23-63 m closer to true locations for three of four distance classes compared to the traditional method (Lenth’s maximum likelihood estimator, LMLE). Additionally, over 99% of 570 triangulations converged for TriAD compared to 85.8% for the LMLE. For toucan data, 98.0% of 4445 triangulations converged in TriAD compared to 88.6% for the LMLE. In Chapter 3, I parameterized SEADS with data from toucan movements and gut retention trials collected in Costa Rica to evaluate the effects of landscape, body size, and social organization on seed dispersal. The larger, less social species dispersed seeds 17-28% farther and in less aggregated patterns than the smaller, social species. This pattern was driven by longer movements in the larger species, suggesting that body size is more important than social organization for seed dispersal in our system. Habitat use and home range sizes limited dispersal distance and dispersion for both species. Findings from our simulations illustrate the importance of separating and quantifying the effects of disperser behaviors and landscape effects that shape seed deposition in fragmented areas.

Rivers in semi-arid regions are highly sensitive and pressured yet can support diverse assemblages of species. In central New Mexico, the Rio Grande (River) is the lifeblood of the Middle Rio Grande Valley (MRGV), a semi-arid region which maintains large urban and agricultural centers and is also the principal wintering area for the Rocky Mountain Population of greater sandhill cranes (Antigone canadensis tabida). Human-induced environmental change has transformed the MRGV and habitat availability prompting concerns for the population. To address these concerns, I investigated dietary and behavioral responses of sandhill cranes to the collection of features that function as winter habitat. In Chapter 1, I demonstrated a novel application of stable isotopes to evaluate dietary reliance of sandhill cranes on corn subsidies provisioned by natural resource agencies, estimated rates of carbon isotope incorporation in tissues of sandhill cranes, and estimated tissue-derived winter arrival dates of sandhill cranes. I found subsidized corn was the primary dietary component of sandhill cranes, rates of carbon isotope incorporation in sandhill crane tissues differed predictably by metabolic activity, and estimated tissue-derived arrival dates on wintering grounds approximated actual arrival dates. In Chapter 2, I advanced a hierarchical Bayesian framework for overcoming challenges and improving analysis of behavioral data frequently generated in animal behavior studies and used behavioral observations of sandhill cranes as a case study. In Chapter 3, I estimated energetic and temporal availability of corn subsidies and seasonal energy requirements of sandhill cranes. I found seasonal energetic requirements of the population are likely satisfied by corn subsides but not without strategic planning. In Chapter 4, I examined how current landscape and riverine configuration influenced patterns of diel habitat selection by sandhill cranes. Sandhill cranes avoided sources of anthropogenic disturbance, relied heavily on managed public land resources, and selected roosting locations in the Rio Grande with a wider channel, interspersion of sandbars and shallow water, and low channel bank vegetation. My research suggests sandhill cranes have coped with alterations that have led to current conditions in the MRGV, however, habitat-related resources will need to be managed adaptively as drivers of environmental change will undoubtedly influence future circumstances.

Many bumblebee species have experienced severe population declines in response to the use of intensive land management practices throughout the UK and western Europe during the latter half of the twentieth century. The loss of wildflower-rich unimproved lowland grasslands has been particularly detrimental and, as a result, in the UK two bumblebee species are now extinct, seven are listed on the UK Biodiversity Action Plan (BAP), and only six extant species remain common and ubiquitous. Populations of the rarer species are often fragmented and restricted to isolated areas, such as the crofting regions of northwest Scotland, in which the use of intensive farming practices has remained relatively limited. Consequently, in this study I primarily focus on the conservation of B. distinguendus and B. muscorum, two of the UK’s rarest species which have strongholds in the Outer Hebrides. In this region crofting is the dominant form of agriculture, and is traditionally typified by small-scale mixed livestock production accompanied by rotational cropping activities. With the use of very few artificial inputs, traditional crofting activities are environmentally sensitive and promote the diverse wildflower assemblages characteristic of the machair which provide suitable forage for bumblebees. However, the changing demographic structure of the islands, in conjunction with a range of other socio-economic factors, is resulting in the adoption of more intensive land management practices by crofters and changing the nature of the crofted landscape. These changes are likely to have a detrimental impact on the rare bumblebee populations that rely on crofting to provide suitable foraging habitats. Neglecting to examine the socio-economic issues behind the decline in crofting activities, and failure to develop a means of making the system economically viable and sustainable, is likely to reduce the effectiveness of any bumblebee conservation measures introduced in the region. Through my research I address this socio-ecological problem by taking an interdisciplinary approach, and combine the two disciplines of ecology and economics to find a way to ensure crofting is sustainable whilst promoting sympathetic land management practices to aid bumblebee conservation. The results of my research demonstrate that current croft land management practices do not support high abundances of foraging bumblebees in the Outer Hebrides, and that sheep grazing during the summer has a particularly negative impact on bumblebee abundance on croft land. My research also highlights the importance of non-agricultural habitats for foraging long-tongued bumblebee species in agricultural landscapes. Grazing management can promote bumblebee abundance, with cattle grazing providing a valuable foraging habitat for short-tongued bumblebees in southwest England. Therefore, to conserve bumblebees in agricultural landscapes the type of farming system needs to be taken into account in developing grazing management regimes, whilst non-agricultural habitats need to be integrated into local land management plans to ensure the provision of forage for bumblebees throughout the flight period. The outputs of the ecological-economic models show that compensation payments are not always required to encourage beneficial land management practices to enhance bumblebee populations in crofted areas. However, crofting is a marginal farming system that is heavily influenced by socio-economic factors, and this should be taken into consideration in the development of future agricultural policy for the region.

Ground pangolins Smutsia temminckii are inconspicuous, mainly nocturnal mammals that occur at low population densities. As a result, there is scant information available on the ecology and physiology of this species. To date the handful of studies focussing on this species were centred in the mesic eastern regions of its range, with no attention being given to ecological and biological traits in arid environments. To address these data shortfalls, a study was undertaken in the Kalahari Desert in northwestern South Africa. Very High Frequency (VHF) transmitters or Global Positioning System (GPS) loggers were fitted to 16 ground pangolins and their ecology and physiology studied over a period of three years. Throughout its range the ground pangolin is increasingly endangered, predominantly due to anthropogenic threats. Previous studies have identified threats facing this species, but very few of these studies included quantitative data as to the extent of these threats. The present study suggests that the main threats to ground pangolins in southern Africa are electrocution on electrified fences, the traditional medicine trade, habitat loss, road mortalities and capture in gin traps. Although accidental poisoning has previously been viewed as a threat, a review of the available literature suggests that this is not the case and that these views stemmed from two isolated incidents of captive animals. Electrocutions probably pose the greatest threat to ground pangolins, with mortality rates of one pangolin per 11 km of electrified fence per year recorded during this study. Home range sizes of this arid-zone population are comparable to the home range sizes recorded in mesic populations. Study animals in the Kalahari had Minimum Convex Polygon (MCP) home range values of 10.0 ± 8.9 km² SD for adults and 7.1 ± 1.1 km² SD for juveniles, in comparison to the 0.17 – 23.38 km² MCP in Zimbabwe and 1.3 – 7.9 km2 MCP in mesic north-eastern South Africa. These results are surprising as arid-zone animals usually have larger home ranges than do their mesic counterparts. It is hypothesised that this discrepancy is due to the fact that ground pangolins in the Kalahari are on average 25 – 30 % smaller than their mesic counterparts. This smaller body size means that individuals require a smaller home range to meet their dietary requirements, which could be counteracting the trend of arid-zone individuals requiring larger home ranges. This research also found ground pangolins to be more active during the day in winter and nearly entirely nocturnal during summer. These changes in photoperiodicity are likely driven by adaptations to the extreme climatic conditions present at the study site rather than predation pressure or changes in food resources, although the latter may be playing a role as well. By being diurnal in winter, individuals avoid the extremely cold night-time temperatures, thus saving energy that would otherwise be spent on maintaining their body temperature. By contrast, becoming nocturnal in summer allows them to avoid the extreme daytime temperatures, thus conserving water. The results of this study reiterate previous findings that ground pangolins are entirely myrmecophagous and highly selective of the species that they eat. Study animals were recorded feeding on only four ant and two termite species, representing 7.5 % and 50 % of the total species richness of each of these families. This is similar to previous research in mesic savannahs where five ant one termite species constituted 97 % of the ground pangolin’s diet. No seasonal differences in prey selection were observed, although the species consumed did depend on the habitats that were available to individual ground pangolins. This study is the first to investigate the core body temperature (Tb) of a free-ranging pangolin. These data indicated that Tb fluctuated cyclically between 32 – 35 °C and reflected the activity periods of the animal, peaking when the animal was active. When the individual was inactive, Tb steadily decreased, suggesting that it used daily heterothermy to cope with the low food availability in this unpredictable environment. In summary, ecological parameters between arid and mesic ground pangolin populations are similar in some respects, but divergent in others. Arid-zone populations are smaller overall and show a higher degree of diurnal activity. Despite this smaller body size, home range values appear to be similar between arid and mesic populations. Although the prey species eaten by ground pangolins in the Kalahari differ from prey species in eastern South Africa and Zimbabwe, they belonged to the same genera and were of similar morphology and ecology. The core body temperature results confirm findings from previous captive studies that pangolin body temperatures are lower than those of other eutherian mammals of a similar size. Furthermore, these data indicate that core body temperature is a lot more variable than previously believed, and thus warrants further study. Overall ground pangolin densities in the Kalahari appear to be double those in eastern South Africa and Zimbabwe, although it is unclear whether this is genuine or whether it is an artefact of individuals being easier to locate in the Kalahari. This study also confirmed that electrocutions are probably the greatest threat to this species, and new threats such as accidental capture in gin traps and road mortalities have also come to light.
Dissertation (MSc)--University of Pretoria, 2013.
gm2014
Zoology and Entomology
unrestricted

Thesis (MScConEcol)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: The confinement of many elephant (Loxodonta africana) populations in southern Africa to fenced reserves has made the management of such reserves difficult as elephants are a keystone species. Elephants are also water-dependent; therefore the availability of water affects the location, extent and intensity of elephant impacts on vegetation. Majete Wildlife Reserve (Malawi) has undergone reform, during which it was fenced, artificial waterholes (AWPs) were created and wildlife reintroduced, including 220 elephants. Concerns have arisen as to the impact elephants may be having on the vegetation. In this thesis, two studies were conducted, along with a review of literature on elephant interactions with surface water. Woody vegetation changes in Majete were assessed by comparing woody vegetation cover datasets (based on remote-sensed vegetation classifications) of the reserve for 1985, 1990, 2000 and 2010. Woody cover loss was high between 2000 and 2010, therefore points of woody cover loss were further analysed in a spatial analysis. Using spatial and non-spatial environmental data, the effects of rainfall, fires, terrain (altitude, aspect, slope, hill and valley characteristics) and proximity to perennial water on woody vegetation cover were tested. Data analyses indicated that woody cover loss may have been caused by differing combinations of drought and herbivory or fire in different areas of the reserve. Where woody cover loss was attributed to herbivory, points of loss were not associated with proximity to perennial water. It was suggested that this is due to high perennial water availability in Majete, which would not limit herbivore foraging ranges in the dry season. Woody cover loss could not, however, be attributed to elephants in this study and further information on their use of and impacts around perennial water points was required. In a further study, the hypothesis tested was that different water point types (rivers, AWPs and springs) would be used at different intensities by elephants, and that perennial rivers would experience the most use. Elephant usage (including visits to water points, browsing levels and path use around water points) of selected perennial water points in Majete was monitored in the wet and dry season. The effects of season, water point characteristics (type, size and water quality) and habitat context (surrounding vegetation type, elevation and proximity to other water points) on elephant water point use were then tested. Elephant water point use was affected by season, as well as water point altitude and surrounding vegetation type. In areas of high perennial water availability, elephant browsing around water points did not decrease with increasing distance. It was suggested that this too could be because elephant browsing activity is not limited by water availability in Majete. Based on the findings of both studies, recommendations for water, elephant and fire management in Majete were proposed and discussed.
AFRIKAANSE OPSOMMING: Die beperking van baie olifantpopulasies tot omheinde reservate in Suider-Afrika bemoeilik die bestuur van hierdie parke omdat olifante (Loxodonta africana) as 'n hoeksteenspesie beskou word. Olifante is ook water-afhanklik en daarom word die plek, omvang en intensiteit van olifante se impak op plantegroei deur die beskikbaarheid van water beïnvloed. Die Majete Wildlife Reserve (Malawi) het hervorming ondergaan waartydens dit omhein is, kunsmatige waterpunte (AWP‟s) geskep is en wilde diere, insluitend 220 olifante, hervestig is. Kommer het ontstaan rondom die moontlike impak wat olifante op die plantegroei mag hê. In hierdie tesis word twee studies sowel as ʼn literatuurstudie aangaande olifantinteraksies met oppervlakwater uitgevoer. Houtagtige plantegroei veranderinge in Majete is geassesseer deur data van plantegroei-bedekking (op afstandswaarnemings van plantegroeiklassifikasies gebaseer) vanuit 1985, 1990, 2000 en 2010 met mekaar te vergelyk. Die verlies van houtagtige-bedekking tussen 2000 en 2010 was hoog en gevolglik is hierdie areas verder deur ʼn ruimtelike analise ontleed. Deur die gebruik van ruimtelike en nie-ruimtelike omgewingsdata, kon die effek van reënval, brande, terrein (hoogte, aspek, helling, heuwel- en vallei-eienskappe) en nabyheid aan standhoudende water op houtagtige plantegroei getoets word. Data-analise het aangedui dat verlies van houtagtige-bedekking deur verskillende kombinasies van droogte, herbivooraktiwiteit of brande in die verskillende dele van die reservaat veroorsaak word. Waar verlies van houtagtige-bedekking toegeskryf kon word aan herbivore, was die punte van verlies nie geassosieer met nabyheid aan standhoudende water nie. Daar is voorgestel dat hierdie waarneming verband hou met die hoë beskikbaarheid van water in Majete, wat gevolglik nie herbivoorbeweiding in die droë seisoen beperk nie. Hierdie studie kon dus nie die verlies van houtagtige-bedekking aan olifantteenwoordigheid toeskryf nie en verdere inligting rondom die verbruik en impak van olifante op standhoudende waterpunte word benodig. In 'n verdere studie is die hipotese dat verskillende tipes waterpunte (riviere, AWP‟s en fonteine) teen verskillende intensiteitsvlakke deur olifante benut word, en dat standhoudende riviere die meeste verbruik sou ervaar, getoets. Verbruik van geselekteerde standhoudende waterpunte deur olifante (insluitend besoeke aan waterpunte, beweiding en paadjiegebruik rondom waterpunte) in Majete is gedurende die nat- sowel as droë seisoene gemonitor. Die effek van seisoen, waterpunt-eienskappe (tipe, grootte en watergehalte) en habitatkonteks (omliggende plantegroei, hoogte bo seespieël en nabyheid aan ander waterpunte) is op die waterpuntverbruik van olifante getoets. Die waterpuntverbruik van olifante word deur seisoen, hoogte bo seespieël en omliggende plantegroei beïnvloed. In gebiede met hoë beskikbaarheid van standhoudende waterpunte, het olifantbeweiding rondom waterpunte nie met toenemende afstande afgeneem nie. Daar is voorgestel dat hierdie waarneming ook toegeskryf kan word aan die feit dat olifantbeweiding nie deur die beskikbaarheid van water in Majete beperk word nie. Gebaseer op die bevindinge van beide studies, word daar aanbevelings vir water-, olifant- en brandbestuur in Majete voorgestel en bespreek.

I studied the ecology and distribution of the Florida bog frog (Rana okaloosae) and flatwoods salamander (Ambystoma cingulatum) on Eglin Air Force Base in northwest Florida. I report data on the breeding ecology, population dynamics, home ranges, microhabitat, and distribution of the endemic bog frog and make comparisons to its closest relative, the bronze frog (Rana clamitans clamitans). Bog and bronze frogs occur in the same habitats and are suspected to hybridize. I investigated the potential for auditory and visual mate recognition errors between R. okaloosae and R. clamitans. I also described the vocal repertoire of the bog frog and observed the response of resident males to the playback of unfamiliar conspecific and heterospecific (R. clamitans) calls. The advertisement calls of bog frogs vary among individuals, and individual voice recognition is possible. I exposed tadpoles of bog frogs, bronze frogs, and leopard frogs (R. sphenocephala) to chemical cues from 2 predators, the banded water snake (Colubridae: Nerodia fasciata) and the red fin pickerel (Esocidae: Esox americanus) to evaluate whether swimming behavior or habitat selection differed among tadpole species. The time spent swimming differed among tadpole species and predator treatments, differences which potentially could affect growth rates, survivorship rates, and distribution patterns. Lastly, I discuss the relationship between fire and the federallyâ threatened flatwoods salamander (Ambystoma cingulatum). I compared 13 breeding wetlands with different fire histories in addition to burned and unburned halves of a partiallyâ burned wetland. In general, areas that burned more recently had more open canopies, higher dissolved oxygen concentrations, higher water temperatures, more understory vegetation, and were shallower than unburned areas. Rangewide surveys indicate that prescribed fires typically are applied in winter and early spring in areas inhabited by flatwoods salamanders. Based on what is known about the natural history of the species, the historical burning regime of the longleaf ecosystem, and the effects of fires on ephemeral wetlands, I suggest that land mangers diversify their fireâ management strategy to increase the likelihood of burning the breeding wetlands of flatwoods salamanders.
Ph. D.

A fundamental condition of the struggle for existence is resource limitation. Optimal foraging theory describes how individuals refine behavior to most efficiently exploit available resources. For colonial breeding animals, such as seabirds, competition for limited resources is amplified by a high density of competitors at feeding grounds near the colony, which can lead to a diversification of foraging strategies that best exploit available resources. Laysan and black-footed albatrosses (Phoebatria immutabilis and P. nigripes, respectively) breed sympatrically and synchronously in dense colonies on small atolls throughout the northwestern Hawaiian Islands. While the distributions and habitat preferences of these congeners are well described, the variability in foraging strategies driven by niche partitioning is not. In chapter 1, I used fine-scale behavioral data from GPS data-loggers to tease apart subtle behavioral nice partitioning between and within Laysan and black-footed albatrosses constrained to poor-nutrient tropical waters during the most energetically-demanding reproductive stage in birds: the brood-guard. Albatrosses showed discrete behavioral partitioning both between and within species, which was driven by differences in nocturnal and diurnal foraging and by sex-specific strategies. Black-footed albatrosses exhibited greater variability in foraging patterns suggesting they may experience strong intraspecific competition at Tern Island. In chapter 2, I employed a novel adaptation of a biochemical diet analysis, quantitative fatty acid analyses, to investigate dietary niche partitioning across the breeding season. This analysis characterized diet of individual adult albatrosses across the breeding season, from incubation to the chick-brood, for the first time in these species. Additionally, this research extended beyond diet characterization to quantify dietary dependence on fisheries-associated resources for these two species. One of the primary threats to albatross is the incidental mortality of birds from fisheries bycatch, therefore, understanding the incidence of fisheries-associated food in the diet of a breeding colony of albatrosses could have important conservation implications. While older birds tended to consume more squid than younger birds, we did not identify an age bias in birds that exploited fisheries resources. Parallel with results from the behavioral analysis in chapter 1, I found that black-footed albatrosses had greater dietary flexibility than Laysan albatrosses at a population level, and a greater degree of dietary specialization at the individual level. In the final chapter, I looked at how the obligatory act of flight feather molt impacted activity levels and space use across the post-breed migrations, when albatrosses are freed from central place foraging constraints, but limited by demands of self-maintenance. I found that activity levels, but not habitat use, were impacted by molt extent. Habitat use appeared to be primarily driven by consistent individual preferences, with birds showing a high degree of site fidelity to their post-breeding molting grounds. A clear decrease in home range size with age indicated that birds spend less time searching for profitable feeding grounds when they are older, likely a product of accumulated memory and experience in these long-lived species.

Several avian species exhibit reduced hatching success as a result of mercury contamination, but the mechanism by which this occurs is unknown. We examined egg turning rates and egg temperatures, two important determinants of egg hatchability, in relation to egg mercury contamination of Forster’s terns (Sterna forsteri) in San Francisco Bay. Here, we used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior (sampled at 1 Hz) of 186 tern nests. Overall, adults turned their eggs an average of 3.8 ± 0.8 SD turns h^-1, which is nearly two times higher than that of other seabirds. Egg turning rates also increased with nest initiation date. Changes about the yaw axis (side-to-side egg movements) were the most prominent aspect of egg turning (224 ± 4.7 degrees h ^-1), though roll and pitch (up-and-down movements) also showed substantial changes (149 ± 2.5 degrees h^-1 and 89 ± 1.1 degrees h^-1, respectively). Despite the high variability in egg turning rates among individuals (SD = 0.8 turns h^-1), the rate of turning was not correlated with mercury concentrations in surrogate eggs collected from the same nest. Our results indicate that egg turning rates in Forster’s terns are high, but unrelated to mercury contamination.

Being sprayed by the oil produced by the anal glands of the striped skunk (Mephitis mephitis) is known to be strongly aversive to potential predators, which quickly learn to not attack in the future. However, many trap lures use oil from skunk anal glands as an ingredient intended to attract carnivores. This paradoxical nature of skunk oil being both attractive and aversive to potential predators has yet to be investigated, leaving a gap in the understanding of how predators respond to the visual aposematic warning signal of the skunk’s pelt in combination with the possibly attractive chemical components of its oil. In this study, camera traps with baited models with either black-and-white or brown pelage, either with or without skunk oil, were deployed in natural areas around Southern California. Results suggest despite its previous use as an attractant for carnivores, the skunk’s oil acts as a long distance deterrent while pelt coloration functions as a short distance warning signal.

Thesis (MSc (Conservation Ecology and Entomology))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: During 2007, two evidence-based studies were undertaken in two catchment areas in South Africa. The first study ascertained the relationships between demographic attributes and general awareness, human impacts, attitudes and water use behaviour. The second study determined whether or not State-of-River (SoR) materials developed for foundation phase learners (grades 1 to 3) improved their understanding of and influenced their attitudes towards river conservation. Surveys were conducted amongst learners (n=1178) and parents (n=1144) from different cultures and socio-economic backgrounds. Questionnaires were available in three languages, namely English, isiXhosa and Afrikaans. The SoR reporting materials were not adequately distributed. The first study could therefore not ascertain whether increased awareness or attitudinal and behavioural changes could be ascribed to SoR reporting in the catchments. The majority of respondents (82%) indicated that there was a need for more information on rivers and 60% of the respondents indicated that they would participate in a follow-up survey. Thirty percent of respondents from the Buffalo catchment and 22% of respondents from the Hartenbos and Klein Brak catchment indicated that they use water very sparingly. Respondents from urban areas scored higher in their attitudes towards river conservation and were more aware of water issues than those from rural areas. Both attitudinal and awareness scores did not align with water use behaviour, with rural respondents using water more sparingly. Attitude and awareness improved with increased education levels. Respondents who indicated that they would rather pay more for water than change their water use behaviour showed the lowest score for attitude towards river conservation. Learners from the Buffalo rural area showed a significant increase in understanding the benefits that healthy rivers provide, and this can be ascribed to the distributed SoR activity book and poster. A survey consisting of quantitative and qualitative items, as well as participatory evaluations determined learners’ level of understanding of human impacts on rivers. The quantitative study showed learners from the Hartenbos and Klein Brak area as well as the Buffalo rural area improved the most over time. The qualitative items showed a 35% and 40% increase in the number of correctly listed items as either making a river happy (healthy) or sad (unhealthy) after exposure to SoR materials. Respondents from both catchments taking part in the participatory evaluations displayed an overall increase in their understanding of good practices, as well as the negative impact of human activities on rivers. Those learners that scored low in the participatory evaluations at time 1 showed the most improvement over time, concluding that those learners who knew the least at the start of the study, gained the most understanding of human impacts on rivers. All schools in the Hartenbos and Klein Brak catchment, with the exception of one, showed a slight increase in understanding of human impacts on rivers. Results from the schools in the Buffalo catchment were more variable. Data gathered demonstrated that the SoR materials helped learners to better understand benefits from clean rivers as well as human impact on rivers. Although the learners from urban areas had a better understanding of the concept of river conservation before contact with the SoR materials, learners from the rural areas showed the most improvement over time. There was an increase in the number of learners that showed a willingness to take responsibility for their actions that could impact on river health. Far more learners mentioned remediation types of actions than protection or preventative actions. A change in peoples’ attitudes and behaviour is needed to ensure adequate protection of South Africa’s natural water resources. Imprinting values and perceptions that would last into adulthood need intervention at an early age and throughout children’s’ formative years.
AFRIKAANSE OPSOMMING: Gedurende 2007, twee bewysgebaseerde ondersoeke is in twee wateropvangsgebiede in Suid Afrika gedoen. Die eerste studie was gerig op die bepaling van die verband tussen demografiese kenmerke, algemene bewustheid, menslike impak, houdings en waterverbruik. Die tweede studie het bepaal of die Stand-van-Rivier (SvR) inligtingsmateriaal wat vir grondslagfase leerlinge (graad 1 tot 3) ontwikkel is, bygedra het tot hulle begrip van en houding jeens die bewaring van riviere. Steekproeftrekkings het leerlinge (n=1178) en ouers (n=1144) vanuit verskillende kultuur- en sosioekonomiese agtergronde betrek. Vraelyste was in drie landstale naamlik Engels, Xhosa en Afrikaans beskikbaar. Die SvR kommunikasie material is nie toereikend versprei nie. Die eerste studie kon derhalwe nie bepaal of groter bewustheid of veranderings in houding en gedrag in hierdie opvangsgebiede aan die SvR verslaggewing toegeskryf kon word nie. Die meerderheid respondente (82%) het aangedui dat daar ‘n tekort and rivierinligting is en 60% van die respondente het hulself bereidwillig verklaar om aan ’n opvolgstudie deel te neem. Dertig persent van die respondente uit die Buffels- en 22% uit die Hartenbos- en Klein Brak-opvangsgebiede het aangedui dat hulle water spaarsamig gebruik. Respondente afkomstig van stedelike gebiede het beter rivierbewaringshoudings getoon en was meer bewus van wateraangeleenthede as die van landelike gebiede. Houdings en bewustheids-vlakke het nie ooreengestem met waterverbruik nie – landelike respondente gebruik water meer spaarsamig. Beide houdings en algemene bewustheid het toegeneem met hoër onderwysvlakke. Respondente wat aangedui het dat hulle eerder meer vir water sal betaal as om hulle verbruik te verminder, het die swakste houding jeens die bewaring van riviere getoon. Leerlinge uit die landelike gebiede van die Buffels opvangsgebied het groter begrip getoon vir die voordele wat gesonde riviere inhou, en dit kan toegeskryf word aan die aktiwiteitsboek en SvR plakkaat wat onder hulle versprei is. ‘n Steekproef bestaande uit kwantitatiewe en kwalitatiewe items, sowel as deelnemende evaluasies is gebruik om leerlinge se vlak van begrip van menslike impak op riviere te bepaal. Die kwantitatiewe studie het aangedui dat die begrip van leerlinge van die Hartenbos en Klein Brak sowel as die van die landelike Buffelsrivieropvangsgebiede oor tyd die meeste toegeneem het. Op die vraag wat riviere gelukkig (gesond) of hartseer (ongesond) maak, het die kwalitatiewe items, na blootstelling van die leerders aan die SvR materiaal, ‘n toename van 35% en 40% in korrekte antwoorde getoon. In die deelnemende evaluasie het respondente van beide opvangsgebiede ‘n toename in begrip van goeie praktyke sowel as die negatiewe impak van menslike aktiwiteite op riviere getoon. Leerlinge wat swak gevaar het in die deelnemende evaluasie gedurende die eerste rondte het die meeste vordering getoon. Die gevolgtrekking is dus dat leerlinge wat die minste geweet het aan die begin van die studie, die meeste geleer het oor menslike impak op riviere. Op een na, het alle skole in die Hartenbos- en Klein Brakrivieropvangsgebied ‘n geringe verhoging in begrip van menslike impak op riviere getoon. Resultate van skole uit die Buffelsopvangsgebied het meer gevarieer. Data versamel het gedemonstreer dat die gebruik van die aktiwiteitsboek en plakkate gelei het tot ’n beter begrip by leerders van die voordele van skoon riviere asook van menslike impak op riviere. Alhoewel die leerlinge van stedelike gebiede beter begrip getoon het oor rivierbewaring voor kontak met die SvR material, het die landelike leerlinge die grootste toename in begrip oor die verloop van die studie getoon. Daar was ook ‘n toename in die aantal leerlinge wat bereid was om verantwoordelikheid vir hulle aktiwiteite wat ‘n impak op riviergesondheid kon hê, te aanvaar. Veel meer leerlinge het tydens die tweede fase verwys na herstel eerder as beskermings of voorkomende gedrag. ’n Verandering in mense se houdings en gedrag is noodsaaklik om genoegsame bewaring van Suid Afrika se natuurlike waterhulpbronne te verseker. Waarde sisteme en persepsies wat met volwassewording steeds geldig sal wees, word reeds teen ’n vroeë ouderdom, gedurende kinders se vormingsjare, vasgelê.

The behavioural ecology of duikers (Cephalophus spp.) was studied in mature forest and mixed secondary vegetation around TaI National Park, Cöte d'Ivoire. The most common species in both vegetation types was C. maxwelli, followed by C. dorsalis, C. ogilbyi, C. niger, C. zebra and C. lentinki in mature forest, and C. niger, C. dorsalis and C. sylvicultor in secondary vegetation. Population surveys were carried out by a number of methods. Transect censuses by night were found most efficient in mature forest, whereas in secondary vegetation, only pellet transect censuses and drives into nets were possible. C. maxwelli populations were estimated at about 63 km2 in mature forest and 79 km2 in secondary vegetation. Duikers were primarily frugivorous, but the proportion of leaves taken increased in the season of fruit scarcity. Fruit abundance in different habitats increased with the age of the vegetation. Six C. maxwelli in mature forest and four in secondary vegetation were radio-collared to determine ranging patterns and social behaviour. They were diurnal and lived in groups of one male with one or two females and young. Home ranges, which were about 5 ha in size in mature forest and 3.6 ha in secondary vegetation, were defended by males, and the boundaries were marked by latrine areas by both sexes. In mixed secondary vegetation, all habitats were used except open fields and bamboo thickets. Implications for conservation and management are discussed. The continued preservation of mature forest and the control of poaching are essential for the survival of the three rarer species (C. -jentinki, C. zebra and C. ogilbyi). The control of poaching must precede any programme of sustainable harvesting of the more abundant species, which could be carried out in secondary vegetation. Duiker farming may be possible if low-cost sources of fencing and forage can be identified.

Single-species research dominates the field of ecology; however there is a growing appreciation of the importance of a multi-species approach to holistic conservation. Carnivores exert a top-down control on other species, and are vital components of stable ecosystem functioning. Physiologically adapted for predation upon other animals, competition between carnivores can be particularly aggressive; frequently resulting in mortality, and even population suppression. Big cat research has historically focused on those species that are most easily observable; in particular the lion Panthera leo. The majority of the Felidae however are secretive and elusive, and receive relatively little scientific attention. In particular, there are few data available that measure the effect of direct intraguild interactions between carnivores. Using leopards Panthera pardus as a model species, this research aimed to investigate the impact of lions on the behavioural ecology of a socially subordinate carnivore. Leopards are the most abundant large carnivore in Africa, and have the largest global range of all felids; their ecological niche overlapping with that of both lions and tigers. The knowledge gained from examining their competitive interactions is therefore widely relevant, and may be applicable to other subordinate carnivore species that remain unstudied. Biotelemetry and camera-trap data were modelled using novel algorithms to show that lions impact on leopard population density, demographics and spatial ecology. Faecal analyses suggest that dietary niche segregation may facilitate sympatry. These results indicate the level of impact that large carnivores can exert over smaller species, and the potential for a focus on single-species conservation to undermine holistic conservation. The manifestation of intraguild competition has a significant influence on an animal’s ecology; leopards are generalist species that cope with persecution by adapting their behaviour and niche. Ecological specialists may not fare as well under competitive pressure, and proactive conservation initiatives may be required for endangered species.

This research was designed to investigate cougar response to urbanization, habitat fragmentation, and exploitation from behavioral, demographic, and landscape perspectives. The source-sink model has been proposed as an alternative framework for the management of exploited cougar populations. I addressed the basic question of whether cougars conform behaviorally to the predictions of the source-sink model, and consequently, the applied question of whether the model could be used for the conservation of this species. To achieve this I evaluated three scale-specific questions using radio-telemetry and hunter-harvest data collected from 1996-2010. At the subpopulation scale, I tested the hypothesis that cougars are wildland obligates by measuring cougar response to a suite of anthropogenic land uses. At the meso scale I compared cougar dispersal patterns from two populations under different management. Lastly, at the statewide scale I examined the distribution of human-induced de facto refugia and ecological traps in relation to the species range within Utah. Cougars show a strong proclivity for wildland over rural or suburban habitats, but all cougars used anthropogenic landscapes to some degree, and appear capable of surviving in highly disturbed, human-impacted environments. Cougar dispersal was correlated with maternal estrus; once young animals emigrated, natural and anthropogenic barriers directed movement into habitats marked by frequent human-caused mortality, with females selecting areas of lower conspecific density relative to males. Anthropogenic cougar mortality was disproportionately distributed in accessible, high quality habitats within the core of the species statewide range. Conversely, ecological traps were primarily situated within marginal habitats in remote settings on the periphery of the range. The source-sink model predicts that subordinate animals from saturated populations disperse to habitat with the highest suitability. Cougars of both sexes display behaviors that largely conform to these predictions. Based on the patchy but predictable distribution of cougar exploitation, Utah may already have a quasi source-sink system, which could be formalized through management action. In general, cougars are adaptable, behaviorally plastic, generalist carnivores, and as such defy broad habitat generalizations. These investigations have implications for sustainable hunting and long-term conservation of cougars in the multiple-use landscapes of the Intermountain West.

Noise associated with human activity is widespread and expanding rapidly in terrestrial environments, but there is still much to learn about its effects on animals. To determine the effect of introduced noise on lek attendance and strutting behavior, I played back recorded continuous and intermittent anthropogenic sounds associated with natural gas drilling and roads at leks of Greater Sage-Grouse (Centrocercus urophasianus). For 3 breeding seasons, I monitored sage-grouse abundance at leks with and without noise. Peak male attendance (i.e., abundance) at leks experimentally treated with noise from natural gas drilling and roads decreased 29% and 73% respectively relative to paired controls. Decreases in abundance at leks treated with noise occurred in the first year of the study and were sustained throughout the experiment. There was limited evidence for an effect of noise playback on peak female attendance during the experiment or on male attendance the year after the experiment ended. These results suggest that sage-grouse avoid leks with anthropogenic noise and that intermittent noise has a greater effect on attendance than continuous noise. To quantify the potential for noise from natural gas infrastructure to mask sage-grouse vocalizations over both long and short distances, I analyzed both the individual notes of mating vocalizations produced by male sage-grouse and recordings of such noise. Noise produced by natural gas infrastructure is predicted to mask sage-grouse vocalizations substantially, reducing the active space of detection and discrimination of all vocalization components, particularly impacting notes that are low frequency and low amplitude. Such masking could increase the difficulty of mate assessment for lekking sage-grouse. Significant impacts to sage-grouse populations have been measured at noise levels that predict little to no masking. I investigated whether male sage-grouse adjust the repetition and timing of their strut displays in response to playback of noise associated with natural gas development. I compared the signaling behavior of male sage-grouse on leks with long-term drilling and road noise playback to that of males on similar leks with no noise playback. Males exposed to long-term drilling noise playback strutted at higher rates and in longer bouts than males on control leks, while males on road noise leks strutted at lower rates and in shorter bouts than males on control leks; these differences were only observed during close courtship, when strut rate is most important in influencing female mate choice. I did a short-term playback of intermittent traffic noise and compared the strut timing of individuals during noisy and quiet periods. Males performed fewer struts overall during noisy periods, but male strutting behavior was related to female proximity. Males that were not closely approached by females strutted less during noisy periods than quiet periods and males that engaged in close courtship with females strutted at similar rates during noisy and quiet periods, even when females were far away. Introduced noise associated with natural gas development causes large declines in sage-grouse lek attendance and is likely to cause substantial masking of sage-grouse vocalizations. However, masking is not likely to be the only mechanism of noise impact on this species. Sage-grouse may at least partially reduce masking impacts through behavioral plasticity, adjusting the timing of their signals in a manner that may reduce the impacts of masking on communication.

From all the species that arrive to a novel environment, very few manage to form a viable population. The guppy, a very successful invader, is a highly social species that performs some of its vital tasks (e.g., foraging, avoiding predators) in groups. This thesis aimed to quantify heterospecific association benefits that enhance invasion success. Interactions between invaders and natives could be one of the environmental characteristics of a place that increase its risk of invasion. I evaluated the tendency of an invasive species to associate with native individuals with similar ecological requirements. I tested the hypothesis that invaders gain exploring, acquisition of information and foraging benefits when socializing with natives. In these experiments I used the guppy as the invasive model species and endangered native Mexican topminnows (Poeciliopsis infans, Skiffia bilineata, Ameca splendens, Zoogoneticus tequila, Xenotoca eiseni and Girardinichthys viviparous). I found that guppies shoal with other species in Trinidad (Poecilia picta and Poecilia sphenops), where they are native (Chapter 2) and that this trait remains when they are invasive (Chapter 3). Guppies are equally willing to explore novel environments when accompanied by heterospecifics or conspecifics. Guppies are more willing to explore complex environments than simple ones. Moreover, when exploring simple environments they have a higher association tendency, regardless of the partner' species (Chapter 4), which could lead them to acquire the benefits of grouping behaviour and avoid Allee effects - the disadvantages of being part of a small group. In the contexts in which they were tested guppies gained as much information by associating with heterospecifics as with conspecifics (Chapter 5). Finally, I found that when shoaling in bigger shoals guppies are able to locate food faster and spent more time foraging. The benefits of increased shoal size were maintained when the additional guppies were replaced with heterospecifics. However, they derive more benefits from the species they are more willing to associate with (Chapter 6). These results uncover a mechanism enabling founding individuals to survive during the most vulnerable phase of an invasion and help explain why guppies have established viable populations in many parts of Mexico as well as in every continent except Antarctica.

Asian elephants utilize two chemical signals that have been described to function in reproduction: (1) (Z)-7-dodecenyl acetate (Z7-12:Ac) is released by females near ovulation, and (2) frontalin is released by males around the time of musth. Signaling theory posits that the concentration at which either compound is emitted should have implications for the response of the receiver, varying with factors such as sex and reproductive experience. Here, the objectives were to: (1) investigate the effect of concentration on receiver chemosensory behavior in an effort to identify detection thresholds and concentrations of maximum response for reproductively experienced or inexperienced male and female Asian elephants, and (2) characterize the broader behavioral impacts of each of these compounds in an effort for application as environmental enrichment in captive settings. Concentrations from 0.0 mM to 2.0 mM of both frontalin and Z7-12:Ac were bioassayed simultaneously with captive elephants housed at facilities across North America in two experiments: one that tested mid-range concentrations and a second that tested low and high concentrations. There was a general increase in chemosensory response with increasing concentration of both compounds regardless of sex or reproductive experience. Females exhibited a lower detection threshold for frontalin, and the opposite was true for males with Z7-12:Ac. Reproductive experience also influenced thresholds: inexperienced males had a higher threshold than experienced males for frontalin (the same was true for females), and experienced males were able to detect Z7-12:Ac samples as low as 10–7 mM. Aside from inexperienced males, all elephants responded maximally to the 1.0 mM samples of both compounds. Elephants exposed to mid-range concentrations of either compound showed no notable changes in behavior after application of the signals, although inexperienced males spent less time inactive and more time walking after frontalin bioassays, and inexperienced females foraged more after exposure to Z7-12:Ac. Interpreted together, this suggests that the concentration at which either compound is emitted has strong implications for chemosensory response based on the identity of the receiver in Asian elephants, although it is unclear whether these compounds have other behavioral effects that can be targeted for a goal-oriented olfactory enrichment program.

Fear of predation can have a major impact on the behaviour of prey species. Despite recent codifying of the concept of the ecology of fear, there has been relatively little focus on how these ideas apply to large carnivore species which, although not prey sensu stricto, may experience fear as a result of threats from humans. This thesis argues that large mammalian carnivores are subject to a Landscape of Fear similar to that described for prey species, and will respond behaviourally to fear of human-caused mortality. The idea of a "Landscape of Coexistence" is introduced to denote the perceived risk from humans and associated behavioural responses that can be overlain on spatio-temporally heterogeneous landscapes. Literature on the ecology of fear for large mammalian carnivores and, as there is a dearth of such literature, the current theory on the ecology of fear for other guilds is reviewed, and how this might inform large carnivore behaviour in a Landscape of Coexistence is explored. Behavioural effects of human-caused mortality risk are revealed for lions living in a human dominated landscape (Laikipia County, Kenya), specifically how lions adjust their movement patterns, habitat use and foraging tactics when in proximity to humans. It is argued that these behavioural adjustments represent a trade-off between maximising fitness enhancing activities and minimising the risk of human-caused mortality, thus need to be taken into consideration along with the lethal effects of humans when explaining the density, distribution and behaviour of lions throughout much of their remaining range. Although fear is generic, 'human-caused mortality risk' represents a distinct and very important sub-set of the ecology of fear for the carnivore guild. The existence of a Landscape of Coexistence has implications for understanding their foraging ecology, and ultimately their population dynamics and role in the ecosystem, and is therefore, important for the conservation of large carnivores throughout large parts of their remaining ranges.

The Knysna seahorse Hippocampus capensis is South Africa’s only endemic seahorse species, and is found in only three adjacent estuaries along the southern coast. The conservation of this endangered species is important on a national and international level. This study presents the first research on this species within the Knysna estuary since 2001 and specifically focuses on aspects of its ecology within a residential marina estate (Thesen Islands Marina). The physico-chemical and habitat features of the marina were described and the population ecology, habitat use, and behaviour of the Knysna seahorse were investigated. Physico-chemical conditions within the western section of the marina, characterised by high water current velocities, were similar to that of the adjacent estuary. The eastern section of the marina was characterised by lower water current velocities and higher turbidity. Four major habitat types were identified within the marina canals: (I) artificial Reno mattress (wire baskets filled with rocks); (II) Codium tenue beds; (III) mixed vegetation on sediment; and (IV) barren canal floor. Seahorse densities within the marina were significantly higher compared to densities found historically within the estuary. Highest seahorse densities were specifically found within the artificial Reno mattress structures and within the western section of the marina. Seahorse density varied spatially and temporally and the type of habitat was an important predictor for seahorse occurrence. An experimental investigation found that H. capensis chooses artificial Reno mattress habitat over Zostera capensis when given a choice. GoPro cameras were used successfully to investigate daytime seahorse behaviour within the Reno mattress habitat. Seahorses were more active during the morning, spent most of their time (> 80 %) feeding, and morning courting behaviour for this species were confirmed. However, during the summer holiday period (mid-December to mid-January) few seahorses were observed on camera, which suggests that the increase in motor boat activity and the related increase in noise had a negative effect on H. capensis feeding and courting behaviour. The marina development, and in particular the Reno mattresses, created a new habitat for this endangered species within the Knysna estuary. In addition to the protection and restoration of natural habitats in which H. capensis is found, the conservation potential of artificial structures such as Reno mattresses should be realised.

Brown stink bug, Euschistus servus (Heteroptera: Pentatomidae), is a recently re-emerged pest of cotton in Arizona. It has been present in southwestern desert-grown cotton since at least the early 1900’s, but dropped from primary pest status in the latter half of the twentieth century. Farmers and pest managers did not perceive it as a primary or economic pest until 2011, when elevated numbers of brown stink bugs were reported in isolated valleys of Arizona and southeastern California. Reports increased and became more widespread in the following years. In response to increased abundance of brown stink bug and corresponding cotton boll injury, research was needed to provide information to cotton farmers. First, pest managers needed information on which factors affect the susceptibility of cotton bolls to stink bug feeding (chapter 1). Young bolls are most vulnerable to stink bug injury, and injury is sustained in the first four days of feeding. In addition, research was needed to determine the effects of currently available brown stink bug chemical controls on the broader integrated pest management system in Arizona cotton (chapter 2). Current chemical control options disrupt natural enemy communities, which results in outbreaks and resurgences of other cotton pests. The negative outcomes and additional costs outweigh the benefits of brown stink bug management.

Urbanisation is thought to be the leading cause of habitat loss and ecosystem fragmentation world-wide. Australian urban bird communities are constantly under threat from landscape modification and the associated disturbances. The Perth metropolitan region, Western Australia provides a unique case study to observe the impact of a developing city that is also located in a biodiversity hotspot. The long-term reporting rate of 66 small passerine birds was analysed on a time and spatial scale, utilising 20 years of citizen science from Birdata collected by birdwatchers. The study compared the overall change in reporting rate to changes in the urban environment, focusing on human population density and the canopy cover of native trees. Life history traits were also used to determine if certain groups/guilds of birds responded differently to changes in the urban landscape. This study revealed that a concerning number of urban sensitive native species are in decline and are being replaced by native and exotic ‘urban-exploiters’. Species that were found to be most at risk in this study were foraging specialists, particularly insectivores, small understorey-dependent birds, and species reliant on large bushland remnants. The study also found generalist species and large nectarivorous birds are increasingly dominating the urban community. Australian urban gardens and streets are lined with nectar-rich, seed-producing vegetation both native and exotic; therefore, favouring species that have the ability to exploit novel foraging resources. Significant loss of habitat in lower strata levels, as a result of land clearing, has reduced the connectivity between large bushland remnants. This has led to urban bird communities becoming overrun by species that frequently utilise the upper canopy and/or thrive in open green areas. Many endemic and native species are locally threatened, and by identifying ‘at risk’ species we can better understand the association between environmental and ecological factors and the impact they have on an individual’s urban tolerance.

Lampreys (Order Petromyzontiformes) have existed for over 365 million years and are considered the most ancient group of living vertebrates. Given the socio-economic, cultural, and ecological consequences of declining lamprey populations, it is imperative to address declines by implementing effective conservation management. This thesis explores the conservation issues affecting the European lamprey species pair Lampetra fluviatilis and Lampetra planeri and offers a holistic approach to their management and conservation in relation to anthropogenic impacts. The rapid development of small-scale hydropower provides substantial risk to migrating biota. At the site of an Archimedes screw turbine, damage rates to lampreys that passed through the screw were low (1.5%) and distinct seasonal, and diel, patterns of migration were exhibited by recently transformed juvenile and larval lampreys. Results indicated longer periods of impingement risk than expected. Cumulative potential impacts of multiple hydropower sites on downstream fish passage (including lampreys) should, however, be considered by regulatory agencies when planning hydropower development within catchments. Anthropogenic barriers were also found to intensify differentiation between L. planeri populations and anadromous L. fluviatilis populations. Gene flow was consequently found to be asymmetric due to the barriers allowing downstream movement, whilst obstructing active upstream migration. Samples of 543 European river lamprey Lampetra fluviatilis and European brook lamprey Lampetra planeri from across 15 sites, primarily in the British Isles, were investigated for 829bp mtDNA sequence and 13 polymorphic microsatellite DNA loci. Contrasting patterns of population structure were found for mtDNA (which revealed no differentiation between species) and microsatellite DNA markers. Microsatellite markers revealed strong differentiation among freshwater-resident L. planeri populations, and between L. fluviatilis and L. planeri in most cases, but little structure was evident among anadromous L. fluviatilis populations. There is also evidence that there has been some degree of gene flow between L. fluviatilis and L. planeri since these populations were established. There is much debate as to whether lamprey paired-species constitute distinct species or are divergent ecotypes of a single polymorphic species. Overall, these findings are suggestive of multiple independent divergences of L. planeri from an anadromous ancestor (i.e. L. planeri are polyphyletic). Focus of conservation and management efforts, therefore, needs to be directed towards ensuring the longitudinal connectivity within rivers, and the continued existence of the specific habitats necessitated within lamprey life-cycles. Molecular techniques should be applied to identify genetically differentiated populations of freshwater-resident lampreys. Appropriate measures, such as, the designation of a network of Special Areas of Conservation (SACs), and recognising these populations as distinct Evolutionarily Significant Units, should also be implemented to ensure the survival of these populations.

Wildlife in captivity has a long history of benefiting global conservation goals. Captive animals can raise awareness and appreciation for the conservation of endangered species. Additionally, captive animals can be used as source populations to reintroduce animals back to the wild or to supplement existing wild populations. The rapid increase in amphibian species threatened with imminent extinction has necessitated the creation of dozens of captive-breeding programs. The focus of this dissertation has integrated topics across the spectrum of animals in captivity and the wild, and the results provide useful recommendations for conservation action. First, I describe how market pressures over a 28-year period are causing meteoric increases in the prices of amphibians sold in the pet trade, indicating a high risk of overexploitation. Pet amphibians may facilitate greater understanding and appreciation of amphibians, but the pet trade must be sustainable. Improving amphibian husbandry will increase the number of captive-bred animals available in the pet trade, and it will allow greater production of threatened species for reintroductions. Secondly, by performing a systematic review of husbandry for 289 amphibian species native to the US, I identified a critical lack in taxon-specific husbandry and developed husbandry research prioritizations. Next, I used a combination of laboratory and field studies to examine domestication processes in amphibians by comparing defensive behaviors in two species of captive-bred and wild poison frog. Captive-bred amphibians had significantly reduced defensive behaviors compared to wild conspecifics, likely resulting from habitation processes related to their husbandry. Finally, I performed three reintroductions of the critically endangered Wyoming Toad (Anaxyrus baxteri) in Wyoming, US. I demonstrated how providing a transitionary period, called a soft-release, to captive-bred toads moving to a novel, wild environment can improve reintroduction success. My work illustrates how improving our understanding of the nexus between captivity and the wild can improve conservation action for endangered species.

Anthropogenic noise is an increasingly prevalent global disturbance. Animals that rely on the acoustical environment, such as songbirds, are especially vulnerable to these sounds. Traffic noise, in particular, overlaps with the frequency range of songbirds, creating masking effects. We investigated the effects of chronic traffic noise on provisioning behaviors and breeding success of nesting western bluebirds (Sialia mexicana) and ash-throated flycatchers (Myiarchus cinerascens). Because anthropogenic noise exposure has the potential to interrupt parent-offspring communication and alter vigilance behaviors, we predicted that traffic noise would lead to changes in provisioning behaviors, such as fewer visits to the nest box, for each species. We also predicted the noise to negatively influence one or more metrics reflective of reproductive success, such as nest success, clutch size, number of nestlings or number of fledglings. Importantly, we were able to eliminate self-sorting among individuals with respect to noise and other possible effects of traffic, such as collisions and pollution, by experimentally introducing traffic noise into nest boxes after clutch initiation using playback systems. Our results indicate no effect of traffic noise on S. mexicana reproductive measures, despite seeing changes in provisioning behaviors suggestive of an increased stress response. However, M. cinerascens experienced fitness consequences from chronic anthropogenic noise exposure when combined with the effect of year. Despite equal clutch sizes to flycatchers in boxes with no noise exposure, noise-treated flycatcher nests experienced a reduction in hatching success and subsequent metrics, such as number of nestlings or fledglings relative to control boxes, during the first study year. The year in which we witnessed the decline in nest success for ash-throated treatment individuals coincided with a significant drought year, suggesting that combinations of multiple stressors lead to nest abandonment. In recording provisioning behaviors during the fledgling stage, no difference in provisioning was found between treatment and control ash-throated flycatcher nests. We contrast these species-specific responses to recent observational work on both species in New Mexico and other studies that have examined fitness consequences of noise. Lastly, we stress the importance of these findings in addressing current conservation practices of nest box placement with respect to roads.

Includes bibliographical references.
The coastal waters off South Africa support a significant proportion of the global white shark population, with at least four well-established coastal aggregation sites. How critical these sites are to the southern African and hence global white shark population depends to a large extent, on their levels of residency a nd site fidelity, in relation to potential threats. Here, I attempt to provide such data by studying the annual and seasonal presence of white sharks in False Bay. From 1 April 2004 - 31 December 2007, a total of 68 (46 female, 22 male) sharks, ranging in length from 1.7 to 5 m, were tagged with acoustic transmitters and monitored on an array of 30 receivers, distributed along the Inshore region of False Bay and at Seal Island, for a maximum of 1349 days. I used generalized linear mixed effects models to investigate the effects of season, habitat type, sex, size and time of day on shark presence. Most tagged sharks were immature animals, some of which were detected in the Bay in all months and across all years. In autumn and winter, males and females aggregated around Seal Island, where they fed predominantly on young-of-the-year seals. Sharks, regardless of sex or size, over-dispersed on the South side of the Island at sunrise, where the probability of encountering predator-naïve seals was highest. Shark presence at Seal Island mirrored the spatial distribution of predation around the Island, which was highest on the South side within 400 m of the Island, and at sunrise. In spring and summer, there was marked sexual segregation in presence, with females frequenting the Inshore areas and males seldom being detected in the Bay . Within the Inshore region, female white sharks showed a preference for beach, compared to rocky, mixed and harbour habitats. The preference for beach habitat likely reflects a combination of high prey availability, in addition to an open habitat suitable for detecting and securing prey. Overall, the results confirm False Bay as a critical area for white shark conservation as both sexes, across a range of sizes, show high levels of fidelity to the Bay.

Orientador: João Vasconcellos Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A maior parte dos ambientes naturais têm sido convertidos para uso humano. Estas mudanças estão ocorrendo num ritmo nunca antes experimentado pela natureza. O aumento do conhecimento sobre a estrutura e o funcionamento dos ecossistemas auxilia na busca de respostas de como e que forma estas ações estão afetando os sistemas naturais, e consequentemente no planejamento de melhores estratégias de conservação. Uma das maneiras de acessar os processos ecológicos que são difíceis de monitorar é buscar grupos ou organismos que facilitem o entendimento destas intervenções. A sensibilidade das assembleias de formigas, combinada com a sua importância funcional e amostragem fácil, fazem delas bons organismos para estudos de conservação. O estudo avaliou a estrutura das assembleias de formigas em três unidades de conservação na Floresta Atlântica. As formigas foram amostradas em uma floresta contínua no Parque Estadual da Serra do Mar, sudeste do Brasil, em áreas mais preservadas e menos preservadas. O objetivo foi determinar se a riqueza, a composição e a abundância destes organismos diferem entre as áreas contrastantes em relação ao grau de perturbação antrópica. Os resultados mostraram que a riqueza não foi afetada nas áreas com diferentes históricos de perturbação, mas a composição mudou drasticamente em duas das três áreas. A abundância de formigas cortadeiras foi baixa em todas as áreas e não mostrou diferenças significativas, e a abundância de Ponerinae foi semelhante entre os diferentes contrastes. Os resultados do estudo sugerem que nos sistemas estudados, os efeitos nas assembleias são dependentes da intensidade e da frequência da perturbação, e do tempo de recuperação da área alterada
Abstract: The majority of the natural environments have been converted for human use. These changes are occurring in a level never experienced before by nature. Increased the knowledge about the structure and functioning of ecosystems helps in finding answers about how to and in what way these actions can affecting natural systems, and consequently in the planning of better conservation strategies. One way to access the ecological processes that are difficult to monitor is to find groups of organisms that are affect by these changes. The sensitivity of ant assemblages, combined with their functional importance and easy of sampling makes them excellent organisms for conservation studies. The present study evaluated the structure of ant assemblages in three protect areas in the Brazilian Atlantic Forest. Ants were sampled within a continuous forest in the Serra do Mar State Park, southeastern Brazil, in disturbed and undisturbed areas. The objective was to determine if richness, composition and abundance of ant assemblages differ between contrasting areas in relation to the degree of human disturbance. Results showed that ant richness has not changed between areas with different disturbance history, while the composition has changed dramatically in two of the three areas. The abundance of leaf-cutting ants was low in all sites and showed no significant differences, and the abundance of Ponerinae was similar across the contrasting areas surveyed. Results suggest that in the studied systems, the effects are dependent of the intensity and frequency of disturbance, and also of the recovery time of disturbed area
Mestrado
Ecologia
Mestre em Ecologia

Esta tese apresenta os resultados de um estudo sobre o surgimento de atitudes pró-ambiente, num quadro de inter-relação entre Educação Ambiental e Ecoturismo. Mostra-se aqui que o contato com a natureza é efetivo em gerar atitudes e motivações ambientalistas. A experiência obtida em 16 anos e 107 viagens de Ecoturismo ao Parque Estadual Turístico do Alto Ribeira - PETAR, com grupos de participantes de atividades dirigidas serviu de ponto de partida para a presente pesquisa. Em estudos iniciais, foram feitas entrevistas com visitantes de 10 áreas naturais do Brasil, visando avaliar suas principais motivações para as visitas a essas localidades e foram aplicados questionários a diversos profissionais de Educação Ambiental a respeito de suas motivações pessoais e estratégias mais eficientes para mudanças de atitudes ambientalistas. A principal motivação apontada pelos visitantes foi de ordem afetiva (\"contemplação ou contado com a natureza\", \"repouso ou fuga da rotina\"). Apesar de ser muito marcante na sua vida, os profissionais de Educação Ambiental atribuíram uma importância relativamente menor ao contato com a natureza. Num estudo experimental, em duas replicações, foram comparados grupos que tiveram um contato dirigido com a natureza (em viagem ao PETAR) a outros que serviram de controle, verificando-se possíveis mudanças de conhecimentos, sentimentos, valores, atitudes e vieses paradigmáticos. A visita dirigida gerou mudanças significativas no sentido de uma transformação dos conhecimentos, valores e atitudes em direção a um comportamento pró-ambiente. As viagens dirigidas à natureza, entretanto, não foram suficientes para gerar percepções diferentes em relação aos paradigmas de Desenvolvimento Sustentável e de Sociedades Sustentáveis. Conclui-se que a concepção do Ecoturismo como um \"turismo de destino\" (a natureza) deve ser substituída por uma \"forma de fazer turismo\", na qual o papel do profissional condutor não se resume a \"levar\", mas sim a \"fazer perceber\". Ao promover afetos especiais no contato com a natureza, o Ecoturismo pode gerar mudanças motivacionais significativas para a constituição de atitudes e valores pró-ambiente.
This thesis presents the results of a study on the rising of pro-environmental attitudes, in an interrelation between Environmental Education and Ecotourism. In this paper, it\'s shown that the contact with nature is effective in generating environmentalist attitudes and motivations. The experience acquired in 16 years and 107 ecotourist trips to Parque Estadual Turístico do Alto Ribeira - PETAR (Alto Ribeira Turistic State Park) with groups of participants in directed activities was the starting point for the current research. In initial studies, interviews were conducted with visitors of 10 natural areas in Brazil, focusing on the assessment of their main reasons to visit those places, and surveys were carried out with several Environmental Education professionals aiming at their personal reasons and more efficient strategies for changes in the attitude towards the environment. The main reason pointed out by the visitors was of emotional nature (contemplation or contact with nature, relaxation or an escape from routine). Although the contact with nature is outstanding in Environmental Education professionals´ lives, they gave a relatively smaller importance to it. In an experimental study, in two applications, two groups were compared: one which had a directed contact with nature (in trips to PETAR) and a control group, verifying possible changes of knowledge, feelings, values, attitudes and paradigms. The directed visit generated many meaningful changes in what regards knowledge, value and attitude towards a pro-environmental behavior change. The directed trips to the nature, however, were not enough to create different perceptions of Sustainable Development and Sustainable Societies paradigms. The conclusion reached is that the conception of Ecotourism as \"destination tourism\" (to nature) must be substituted by a \"way of making tourism\", in which the role of the leading professional is not only \"guiding\", but \"making the traveler understand\". When boosting special emotions out of the contact with nature, Ecotourism can generate meaningful motivational changes for the construction of proenvironmental attitudes and values.

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass this information to their offspring, and 2) lambs will be more efficient at utilizing PEG as a medicine against tannins in the presence of mother than lambs which learn without the influence of the mother. This hypothesis was evaluated in four phases: in the first phase, a group of ewes (Experienced) was conditioned to associate the beneficial effects of PEG after consuming a tannin-containing diet. Ewes were offered a meal of high-tannin food and PEG and subsequently, the high-tannin food and grape pomace (GP) with little nutritional and no "medicinal" effects. In the second phase, the experienced and a naïve group of ewes (Inexperienced) were given a choice between the high-tannin food, PEG, and GP. In the third phase, experienced and inexperienced ewes with their naïve lambs, and the group of naïve lambs without their mothers, were exposed to the tannin-containing diet, PEG, and GP. Finally, in the fourth phase, lambs were separated from their mothers, and lambs from all groups were offered a choice between the tannin-containing diet, PEG, and GP. Lambs from experienced and inexperienced mothers showed a higher preference for PEG than lambs exposed without their mothers who tended to show a higher preference for GP. Thus, the presence of mother (experienced/inexperienced) was important for naïve lambs to learn about the medicinal benefits of PEG. This source of trans-generational knowledge could aid in maintaining the information in the herd, increasing the efficiency and reducing the risk of learning about foods and environments exclusively by individual experience.

Le Quetzal Resplendissant Pharomachrus mocinno est une espèce d’oiseau tropical considérée fortement menacée par la perte de son habitat due aux activités humaines. Le Quetzal Resplendissant joue un rôle important de disperseur de graines et constitue le centre de la culture maya passée et présente. Les recherches sur cette espèce couvrent plusieurs aspects de son histoire naturelle et de sa biologie. Néanmoins, à ce jour, il n’y a aucune description détaillée du comportement et de l’écologie acoustiques de cette espèce, condition préalable à une conservation efficace de l'espèce. L’objectif de cette thèse a été d’étudier tout particulièrement le comportement et l’écologie acoustique de P. mocino dans la forêt nuageuse du Guatemala. Une analyse détaillée des vocalisations de P. mocinno, incluant des expériences de propagation de ses vocalisations dans son habitat, a permis d’identifier deux types de vocalisations destinés à la communication à longue distance et deux autres types de vocalisations destinés à la communication à courte distance. La quantification des différences dans les vocalisations territoriales des deux sous-espèces de Quetzals Resplendissants, P. m. mocinno (partie nord de l’Amérique centrale et sud du Mexique) et P. m. costaricensis (sud de l'Amérique centrale) a révélé de nettes différences entre les sous-espèces, ce qui conforterait l'hypothèse d’espèces distinctes. L'observation de l'espèce dans la canopée dense est difficile et la manipulation des individus est controversée en raison de sa grande importance culturelle. De fait, un système acoustique automatique a été mis au point pour suivre l’espèce de manière non invasive. Le système s'est avéré efficace et a produit des résultats révélant des profils de suivis acoustiques en partie dépendants de variables environnementales. Enfin, la communauté acoustique des oiseaux à laquelle P. mocinno appartient a été analysée afin d’évaluer les interactions interspécifiques de compétition. Les recherches développées ici devraient aider aux décisions de conservation futures concernant le Quetzal Resplendissant et son habitat, la forêt nuageuse. Cette recherche montre également que l'écoacoustique peut constituer une stratégie utile pour aborder les problèmes d'écologie et de conservation dans les zones tropicales
The Resplendent Quetzal Pharomachrus mocinno is a tropical bird considered in a high risk of danger. Degradation of its habitat caused by human activities is the principal menace. The Resplendent Quetzal is important as seed disperser and is the centre of the past and present Mayan culture. The available studies about the species have covered aspects of the natural history and biology. Nevertheless, the description of the acoustic behaviour and ecology, a prerequisite for the conservation of the species, was not available. The general aim of this PhD thesis was to investigate the acoustic behaviour and ecology of P. mocinno in the cloud forest of Guatemala. A detailed analysis of P. mocinno vocalizations, including propagation experiments of these vocalizations in its habitat, led to identify two vocalizations intended for long range, and two for short range communication. Quantification of acoustic parameters in territorial vocalizations of the two subspecies of the Resplendent Quetzal, P. m. mocinno (north part of Central America and Chiapas) and P. m. costaricensis (south part of Central America), revealed clear differences between the subspecies, that could support a species separation hypothesis. . The observation of the species in the dense canopy is difficult and manipulation of individuals is controversial due to its high cultural importance. Then, an automatic acoustic system was developed as a method to study the species in a non-invasive way. The system proved to be efficient and returned results that revealed acoustic patterns linked to environmental variables. Finally, the acoustic community of other bird species P. mocinno belongs to was analysed so that interspecific competition interactions could be assessed. The research here developed should help in future conservation decisions about the Resplendent Quetzal and its habitat, the cloud forest. This research also illustrates that ecoacoustics can be a valuable strategy to tackle ecology and conservation questions in tropical areas