Typescript (photocopy). / Digitized by Kansas Correctional Industries

Evidence suggests that toxic stressors introduced early in development have prolonged effects on neuronal function due, in part, to the maturation of the hypothalamic- pituitary- adrenal (HPA) axis during adolescence. Early life stress has been implicated as a driver of mood and anxiety disorders, like depression and post-traumatic stress disorder - the extent to which appears to be sex dependent. While it is known that early life stress results in several consequences in adulthood, the mechanisms by which these changes manifest are unclear. Stress-induced changes in mood and behavior are often associated with alterations in inflammatory reactivity in both the brain and in the periphery. Previous work from our lab, and others, demonstrates that both male and female rats respond to chronic adolescent stress (CAS) but may differ in inflammatory markers within the brain and periphery and in the induction of negative affective-like behaviors. Inflammatory reactivity has been targeted as a means of identifying how these sex differences arise in studies of chronic stress in adults. Circulating concentrations of inflammatory cytokines have not been directly employed as predictors of behavioral outcomes of stress exposure in adolescence but may be a useful tool in uncovering mechanisms that protect or predispose an organism from the effects of chronic stress. To further assess immunological and behavior deficits following chronic stress in adolescence, the current work used a model of chronic adolescent stress where male and female adolescent mice were exposed to a predator stress for 15 consecutive days. In late adolescence, these mice were treated with an acute inflammatory challenge with lipopolysaccharide (LPS)to elicit an inflammatory response. We predicted that chronic, predatory stress experienced during adolescence would induce negative anxiety-like behaviors and alter circulating proinflammatory levels. Furthermore, we expected females to be more susceptible to the effects of adolescent stress than males. We observed that, chronic, predatory stress during adolescence increased anxiety-like behaviors in males and females, but did not alter social behaviors during late adolescence. Predatory stress also impacted circulating levels of TNFα, but no sex differences in LPS-induced cytokine concentrations were apparent.

Foraging presents a significant challenge for neonatal predators. Both physical maturation and predatory experience may improve predatory abilities. To tease apart which improvements in predatory abilities were due to increased maturation and which to increased experience, several experiments that isolated the effects of maturation and experience were conducted. Individual whitespotted bamboosharks, Chiloscyllium plagiosum, improved predatory efficiency with both maturation and experience. Physical maturation, when isolated from experience, improved predatory efficiency of naïve sharks foraging on shrimp, an elusive prey, but not of sharks foraging on worms, a non-elusive prey. Predatory experience, when isolated from maturation, improved predatory efficiency of sharks foraging on worms but not of sharks foraging on shrimp. Both maturation and experience are important in the development of whitespotted bamboosharks' predatory abilities and may influence the type of prey they can exploit. To determine whether whitespotted bamboosharksare able to retain the ability to capture and eat prey after a period of prey absence, sharks that had 20 days of foraging experience were denied access to live prey for 18 days, after which they were re-exposed to live prey. Predatory efficiency of sharks did not decrease during the 18 day prey-absence period. After sharks were re-exposed to live prey, their predatory efficiency was similar to that of sharks of the same age with equivalent experience but no prey-absence period, but was higher than that of naïve sharks. Whitespotted bamboosharks retain the ability to catch and consume prey after a short period of prey absence. This retention may improve their ability to forage on prey that is spatially or temporally patchy. To determine whether experience with one prey type affects the whitespotted bambooshark's ability to forage on novel prey, sharks that had 20 days of experience foraging on one type of prey (either worms or shrimp) were given foraging trials with the other prey. Experience with one prey improved sharks abilities to forage on novel; sharks foraging on novel prey were as efficient as sharks that had foraged on that prey for 20 days. Whitespotted bamboosharks can maintain or easily modify many predatory skills when foraging on novel prey.

Recent research has focused on the non-lethal effects of predator intimidation and fear, dubbed non-consumptive effects (NCEs), in which prey actively change their behavior and habitat use in response to predator chemical cues. Although NCEs can have large impacts on community structure, many studies have ignored differences in predator population structure and properties of the natural environment that may modify the magnitude and importance of NCEs. Here, I investigated the roles of predator size and density (i.e. biomass), as well as habitat characteristics, on predator risk assessment and the magnitude of consumptive and NCEs using blue crabs, mud crabs, and oyster prey as a model system. Predation experiments between blue crabs and mud crabs demonstrated that blue crabs consume mud crabs; however, the consumptive effects were dependent upon blue crab body size and habitat type. When mud crabs were exposed to chemical cues from differing biomasses of blue crabs in laboratory mesocosms, mud crab activity and predation on oysters was decreased in response to high biomass treatments (i.e. large and multiple small blue crabs), but not to low biomass predators (i.e single small blue crab), suggesting that risk associated with predator size is perceptible via chemical cues and is based on predator biomass. Further experiments showed that the perception of risk and the magnitude of the NCEs were affected by the sensory cues available and the diet of the blue crab predator. The NCE based on blue crab biomass was also demonstrated in the field where water flow can disperse cues necessary for propagating NCEs. Properties of water flow were measured within the experimental design and during the experiment and confirmed cage environments were representative of natural conditions and that patterns in NCEs were not associated with flow characteristics. These results affect species conservation and commercial fisheries management and demonstrate that we cannot successfully predict NCEs without considering predator size structure and the contexts under which we determine predator risk.

This thesis uses data collected over three summers in 2010, 2011 and 2012 at the Isle of May National Nature Reserve, Scotland to examine top predator presence and behaviour in a moderately fast tidal stream site. Fieldwork consisted of an intensive land based observation survey of seabirds at sea, acoustic monitoring of small cetaceans and the deployment of a suite of oceanographical tools to simultaneously collect data on a fine temporal scale over a study area of ~1.5km2. The aim of the study was to examine the potential effects of marine renewable energy developments on top predator behaviour in a tidal stream site by addressing some of the key data gaps such as habitat use in tidal stream areas, dive behaviour and collision and disturbance risk assessment. Acoustic detections of harbour porpoises were investigated as a function of physical environmental variables. Strong links between porpoise presence and increased thermal stratification and chlorophyll levels were detected along with a very strong diurnal pattern with increased detections at night. There was no relationship with tidal state. The habitat use of five species of breeding birds at sea adjacent to breeding cliffs was examined to gauge what environmental factors drive habitat use at these sites. Counts of foraging kittiwakes were examined in relation to environmental variables and while strong temporal trends emerged there was no link with oceanographic features. The study site was predominately used for loafing (non foraging behaviour) and so species specific temporal variation in loafing behaviour was analysed. Strong seasonal and diurnal trends in loafing emerged for all species which could be linked to differences in their breeding phenology. These results can be used in assessing and mitigating disturbance to these birds from marine renewables developments. Age specific variation in dive behaviour in the European shag was examined to determine whether newly fledged juveniles were at a greater risk of collision with tidal turbines than adults. Juveniles initially demonstrated a shorter dive duration than adults but after 4-6 weeks their dive duration had significantly increased. However age specific difference in dive behaviour in relation to water depth iii remained unchanged over time with juveniles showing no relationship between dive duration and water depth while adults increased dive duration in deeper water. The implications of this result for assessing age specific collision risk for this species is discussed. Results from this study were used to populate a framework for assessing collision and disturbance risk to seabirds in the near shore area adjacent to the breeding colony from a small scale tidal turbine development scenario. A method was developed to quantify risk by combining relative abundance data, behavioural data and published data on activity budgets for four species; guillemots, razorbills, puffins and shags. The output from this thesis has practical applications for informing the temporal and spatial scale of data collection and survey design in environmental impact assessments regarding marine renewable energy developments with emphasis on understanding the mechanistic links driving predator behaviour. Results can also be used to design appropriate mitigation procedures to prevent disturbance to loafing or foraging birds.

Thesis (M.Sc.)--College of William and Mary. / Vita. Includes bibliographical references. Also available via the World Wide Web.

Thesis (M.S.)--Eastern Illinois University, 2009. / Includes bibliographical references.

Thesis (M. Sc.)--University of Canterbury, 2008. / Typescript (photocopy). "June 2008." Includes bibliographical references (leaves 74-84). Also available via the World Wide Web.

This study is concerned with some of the processes that occur during the development of behaviour, and these are examined in the context how predatory behaviour develops in domestic cats, initially some of the problems that have beleaguered the study of behavioural development are examined and current issues in this field ae outlined. The experimental design of the study, the definitions of recorded behaviour and the methods of data analysis are then discussed. The study then focusses on the multiple effects that experiences in development can have on adult behaviour. It shows that cats were better able to catch prey as adults if they had had experiences of it as kittens, that cats specialized on the type of prey with which they had had prior experiences, and that little generalization to other prey types occurred in cats with experience of one prey type. Several other factors likely to affect adult predatory behaviour were than examined. Both the presence of the mother during kittens' exposure to prey, and experience of prey as adults were found to improve adult predatory competence. Object play had no effect on predatory behaviour. The study went on to relate the development of social play in kittens to the development of predatory behaviour. Some aspects of play became more associated with predatory behaviour aspects grew older, others less so. Different patterns of play appeared to increasingly come under separate types of control as kittens developed. One of the factors affecting the development of predatory behaviour, the effect of the mother, was then examined in detail. Some of the ways in which mothers encouraged their offspring to interact with prey were outlined together with the ways that offspring responded to the mother's predatory behaviour. Finally, the relationship between predatory behaviour in kittens and their subsequent predatory behaviour as adults was investigated. Many aspects of kitten predation were found to correlate with adult predatory activity. Some individuals that were poor predators as kittens showed competent predatory behaviour as adults. The implications of those findings were discussed in relation to the development of predatory behaviour, the development of play and the timing of events in kitten ontogeny.

Orientador: Sérgio Antonio de Bortoli / Banca: Nilza Maria Martinelli / Banca: Elisângela de Souza Loureiro / Resumo: Este trabalho teve como objetivo avaliar a capacidade predatória, aspectos comportamentais, reprodutivos e estabelecer a curva de resposta funcional do predador O. insidiosus predando ovos e lagartas de primeiro ínstar de Diatraea sacchara/is, P/utella xy/ostella, Spodoptera frugiperda e Anticarsia gemmatalis, e ninfas de terceiro/quarto ínstar de Aphis gossypii. Além destas avaliações, observou-se alguns aspectos reprodutivos de O. insidiosus, todos em função das diferentes densidades de A. gossypii. Para as espécies estudadas o predador apresentou curva de resposta funcional tipo 11, mostrando uma tendência de estabilização nas densidades mais altas. A taxa de ataque foi de 42,16; 9,35 e 22,81 ovos/hora e o tempo de manipulação de 1,56; 1,91 e 1,74 horas, para S. frugiperda, A. gemmatalis e P. xy/ostella, respectivamente. Observou-se também uma baixa capacidade predatória do O. insidiosus sobre ovos de D. saccharalis, proporcionando valores quase nulos para taxa de ataque e tempo de manipulação. A taxa de ataque foi de 15,55; 18,06; 1,77 e 3,68 lagartas/hora, e o tempo de manipulação de 2,13; 1,32; 0,86 e 1,99 horas para S. frugiperda, A. gemmatalis, D. saccharalis e P. xy/ostella, respectivamente. Para A. gossypii a taxa de ataque foi de 0,10 pulgão/hora e tempo de manipulação de 1, 82 h. O predador passou de 3,10 a 4,08 h se alimentando de seiva no nectário foliar do algodoeiro, não tendo a densidade da presa influência direta sobre esse comportamento. A proporção de postura por fêmea foi crescente até 10 ninfas, enquanto a proporção do número de ovos por postura aumentou com o aumento de presas disponíveis. / Abstract: The aim of this research was to evaluate the predatory capacity, behavior aspects and to establish O. insidiosus functional response curve preying Diatraea saccharalis, P/utella xy/ostella, Spodoptera frugiperda and Anticarsia gemmatalis eggs and first instar larvae, and Aphis gossypii third/fourth instar nymphs. By these evaluations it was observed some reproductive aspects of O. insidiosus, in function of A. gossypii different densities. The functional response type 11 was observed for ali species, showing a tendency of stability in the highest densities. The attack rate was 42.16, 9.35 e 22.81 eggs/hour and the handling time 1.56, 1.91 e 1.74 hours for S. frugiperda, A. gemmatalis and P. xy/ostella, respectively. It was also verified a low predatory capacity of O. insidiosus on D. saccharalis eggs, with almost null values for attack rate and handling time, making them despicable. The attack rate was 15.55,18.06,1.77 and 3.68Iarvae/hour, and the handling time 2.13, 1.32,0.86 e 1.99 hours for S. frugiperda, A. gemmatalis, D. saccharalis and P. xy/ostella, respectively. For A. gossypii the attack was 0.10 aphid/hour and the handling time 1.82 h. The predator teal on cotton sap and foliar nectary for 3.10 to 4.08 h, and there was no straight influence of the prey on this behavior. The egg-Iaying by female was crescent, until 10 nymphs, while the egg rate by egg-Iaying increased as the number of preys increased. / Mestre