<p> Marine resources are characteristically patchy and concealed beneath the surface of a "featureless" ocean, which makes facilitative species interactions especially advantageous to seabirds. My research addresses how behavioral mechanisms accommodate prey availability, or more specifically, how common (<i>Sterna hirundo</i>) and roseate terns (<i>S. dougallii </i>) locate and access food when it is not easily detectable. I study their foraging behavior and ecology from pre- to post-breeding, offshore in the pelagic realm (chapter 1), around the colony (chapter 2), and in nearshore waters (chapter 3). My first chapter tests the hypothesis that, as broadly-ranging seabirds, common and roseate terns forage over habitat where marine mammals and predatory fish help to find and access prey. I quantify the spatial association among foraging terns, tunas, dolphins, and their habitat, using Bayesian hierarchical models, and tests of behavioral community interactions. Facilitation explains how terns benefit from subsurface predators through local enhancement and commensal relationships: foraging tunas improve the detection and availability of prey by signaling their presence, and driving them to the surface. Chapter 2 evaluates the link between resource utilization and foraging strategy, measured by nest provisioning and patterns among foraging routes or feeding flocks. I propose that the opportunistic generalists, common terns, depend more on social cues than the specialists, roseate terns, which rely more heavily on spatial memory to find predictable prey. The results support this and suggest that increased breeding and foraging success in roseate terns relates to higher quality and abundance in their preferred prey, sandlance (<i>Ammodytes </i> spp.); in contrast, common terns seem to endure prey limitation through their use of local enhancement. In my third chapter, I hypothesize that habitat variability and prey availability predict interspecific differences in tern foraging. Behavioral tests and density-surface models, with distance sampling, show that foraging common and roseate terns respond positively to the distribution and abundance of each other and their preferred prey. Clearly, common and roseate terns use conspecifics, heterospecifics and subsurface predators to encounter prey via facilitation: such interactions create dynamic hotspots that need to be considered in an ecosystem approach to marine spatial planning.</p>

<p> Factors associated with rank position are poorly understood whereas even fewer studies assessed if benefits were associated with increased rank position when resources were unlimited. I assessed whether age, body mass, size, and testosterone levels were important in rank establishment among 132 captive female white-tailed deer (<i>Odocoileus virginianus</i>. I also assessed if the benefit metrics of improved body condition, decreased stress level, and earlier parturition date were related to rank position. Deer in each of 9 study pens had a linear hierarchy with a mean h' of 0.39 (SD = 0.09). Rank position was moderately related to age (P &lt; 0.1) and was strongly related to body mass and size (P &lt; 0.01). There was no relationship between benefit metrics and rank position (P &lt; 0.1). Although increased body mass, size, and age improved rank position there were no benefits associated with increased rank when resources were unlimited.</p>

<p> Opioids are used for the clinical treatment of pain, but can lead to tolerance and addiction. In this project we examined the role of the serotonin (5-HT) system originating from the dorsal raphe nucleus (DRN) during morphine exposure, withdrawal, abstinence and following an acute stressor capable of initiating behavioral relapse. Following four days of morphine exposure rats showed a preference for the morphine paired side of the conditioned place preference (CPP) chamber. After four days of morphine abstinence, rats showed no net preference for the morphine paired side. The next day rats were exposed to forced swim stress and returned to the CPP chamber where they demonstrated stress-induced reinstatement. Utilizing whole-cell patch-clamp we demonstrated an increase in the amplitude of inhibitory post-synaptic currents (IPSCs) in 5-HT DRN neurons, but not non 5-HT DRN neurons of morphine-conditioned subjects. Next the stress neurohormone corticotrophin releasing factor (CRF) was administered in vitro instead of forced swim. We found an increase in CRF-R2-mediated inward current of 5-HT DRN neurons in animals with a morphine history. From this experiment we concluded that morphine history sensitizes 5-HT DRN neurons to the GABAergic inhibitory effects of stress and to some of the effects of CRF. In the next series of experiments we surgically implanted either morphine or placebo pellets in rats for 72 hours to create physical dependence. The pellets were subsequently removed, and animals experienced up to seven days of abstinence with and without forced swim stress exposure. Real time quantitative PCR was used to measure the mRNA levels of genes at multiple points across this timeline. We examined genes involved in trophic support, stress responses and 5-HT regulation. We determined that mRNA levels for brain-derived neurotrophic factor (BDNF) and the BDNF receptor TrkB were downregulated after opiate exposure, and again following seven days of abstinence. Following seven days of abstinence there was a decrease in mRNA levels of the CRF-R1 receptor and an increase in mRNA levels of the CRF-R2 receptor. During acute opiate exposure there was a decrease in mRNA levels for the autoregulatory 5-HT_1A receptor. Finally following forced swim, there was an increase in mRNA levels of the 5-HT synthesis enzyme TPH2. Collectively these results indicate that a morphine history in abstinent subjects may produce hypofunctioning of the 5-HT DRN system induced by multiple neurochemical mechanisms and this dysregulation may enhance vulnerability to stress-induced relapse.</p>

<p> Abstract As invasive predators spread across landscapes, their sudden presence may have significant effects on the behavior patterns of their new found prey. Here, I examined how predator-naive foxes responded to colonization by non-native golden eagles on Santa Cruz Island, California. First, using radio-telemetry, I investigated the effects of this diurnal, aerial predator on fox activity patterns. In 1992, just prior to the arrival of golden eagles, foxes showed substantial diurnal activity, but diurnal activity was 37.0% lower in 2003-7, after golden eagle colonization; concurrently, overall activity declined and nocturnal activity increased. Moreover, on nearby Santa Catalina Island, where golden eagles were absent but where the fox population recently crashed due to a disease epidemic, remaining foxes were significantly more diurnally active than were those on Santa Cruz Island. The weight of evidence suggested that the change in activity pattern was a response to predation, not to low population density, and that this was probably a heritable, rather than a learned, behavioral trait. Second, I used radio-telemetry, camera traps, sightings to investigate spatial patterns and habitat use in the wake of eagle colonization. When comparing pre- and post-colonization conditions, foxes demonstrated an inverse home range-density relationship, as fox core areas and home ranges expanded significantly in the low-density conditions following eagle colonization. I found that diurnal ranges were 11% smaller than nocturnal home ranges in post-colonization conditions, perhaps reflecting restricted diurnal movement as a form of predator avoidance of the diurnally hunting eagles. In terms of habitat preference, foxes preferred shrubland &ndash; a habitat which provides cover from aerial predators &ndash; over other habitat types. This suggested a way in which foxes may have mitigated golden eagle predation risk. Finally, I examined changes in fox diet before and after colonization using scat analysis. Because this invasion reduced the endemic fox population by 95% in a decade, these dietary changes could have been be attributed to behavioral change (e.g., reduced diurnal activity and movement), demographic change (e.g., reduced intra-specific density), and/or community level change (e.g., increased intra-specific competition with island spotted skunks), all of which were shifts associated with eagle predation. Concurrently, there were marked changes in the island's vegetation community, with the removal of introduced grazers and the subsequent increase in recruitment of shrubland. I hypothesized that these effects would cause fox diets to differ from historic diets, as indicated by scat analysis. I also evaluated seasonal differences and dietary breadth in the post-eagle colonization period. Although I did not observe an overall large scale modification of fox dietary patterns, statistically significant dietary changes were observed before and after eagle colonization. Results suggested that all four factors may have had an effect on fox diet, although evidence suggested that grazer removal may have had a more pronounced effect. Seasonal patterns and dietary breadth reflected the seasonal availability of fruiting shrubs in the dry season, and an emphasis on other food items, primarily mice and insects, in the wet season, as expected. While this fox population has subsequently rebounded successfully, understanding how animals respond to the sudden arrival of an invasive predator is crucial to improving approaches to conserving endangered species in the future.</p>

<p> 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 (<i>Centrocercus urophasianus</i>). 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.</p>

<p>Among rhesus macaques, bi-directional aggression may occur between animals with shifting or ambiguous ranks, or between those whose relative ranks are well established. Factors that influence the latter case (here termed "insubordinate aggression") are not well understood. These factors are of interest because insubordinate aggression may be associated with stability in dominance relationships, and stability in dominance relationships is critically related to group stability. We hypothesized that in well-established female dominance relationships, the likelihood of insubordination during conflicts is influenced by characteristics of both opponents. Multivariate analysis of 11,591 dyadic conflicts among females in six captive rhesus groups shows that dyadic and individual characteristics related to weight, rank, age, and access to social support affect the likelihood of insubordinate aggression. As expected, insubordinate aggression is less likely to occur among dyads with high disparity in weight. The effects of age, rank, and access to social support are more complex. Increasing subordinate age is associated with increased modulation of insubordinate aggression according to opponent age. Age-based deference, i.e. suppression of insubordination associated with opponent age, decreases with increasing age of the lower-ranking opponent. Similarly, dyadic rank disparity has different effects on insubordination rate according to the age of the subordinate opponent. As females age, their likelihood of insubordination is less dependent on the degree to which they are outranked by their opponent. Also, the lower-ranking opponent's level of social support significantly affects her likelihood of insubordination, but the dominant animal's level of social support does not affect her likelihood of receiving insubordination. We predicted that for the lower-ranking opponent, having many maternal kin would promote insubordinate behavior, whereas for the higher-ranking opponent, having many maternal kin would inhibit insubordination. However, our results show that the dominant's matriline size has no effect on her likelihood of receiving insubordination. Further, matriline size has the opposite of the predicted effect for subordinates--subordinates with many maternal kin are significantly less likely to be insubordinate than those with few kin. We propose some possible explanations for this, which will require further investigation. Taken together, this research suggests that females gauge their degree of deference to dominants based on their own characteristics relative to their opponent's, taking into account size, age and weight differences as well as their own access to social support. Features of subordinate animals emerge as more important than those of dominants in determining the likelihood of insubordinate aggression in dyadic conflicts. Understanding determinants of insubordination will contribute to management practices aimed at maintenance of group stability, as the ultimate act of insubordinate aggression, social overthrow, poses a major welfare and management problem.

<p> This dissertation concerns the southern resident killer whales (Orcinus orca), a genetically isolated population of fish-eating killer whales that frequent the international waters of the Salish Sea between the United States and Canada in the eastern Pacific Ocean. Research was conducted from June 1 to October 31, 2007 and from June 7 to October 31, 2008, between geographic coordinates: 48&deg;12&rsquo; to 49&deg; N latitude by 122&deg;43&rsquo; to 123&deg;50&deg; W longitude. </p><p> The southern resident killer whale population has experienced multiple fluctuations since population surveys were initiated by the Center for Whale Research (CWR) in the mid 1970's. In November 2005, the U.S. National Oceanic and Atmospheric Administration's National Marine Fisheries Service (NMFS), Northwest Regional Office listed the southern resident killer whales as an endangered distinct population segment of the species <i>Orcinus orca </i> under the United States Endangered Species Act (ESA). Several risk factors including reductions in the quantity and quality of prey (salmon), exposure to persistent toxins, and disturbance from vessel presence and associated noise were identified as contributing to the decline of this already small population. With the listing under the ESA, critical habitat was designated in the inland waters around the U.S. San Juan Islands, Washington State and the Canadian Gulf Islands, British Columbia, Canada. </p><p> Chapter one, <i>Managing Vessel-based Killer Whale Watching: A Critical Assessment of the Evolution from Voluntary Guidelines to Regulations in the Salish Sea,</i> provides background on the southern resident killer whales and the robust international whale watching industry in the region. This chapter also provides a detailed history of local, state, federal and international vessel laws and guidelines for watching whales in the Salish Sea. </p><p> Chapter two, <i>Non-invasive methods to study southern resident killer whales and vessel compliance with regulations,</i> describes a novel equipment package, consisting of a differential GPS integrated with a digital compass and laser rangefinder that allowed me to collect accurate geo-referenced locations and behavioral data on whales and vessels throughout the whale's critical habitat. To improve both the spatial and temporal data on whale-vessel interactions, the information collected with this equipment was used to assess vessel compliance with local, state and federal laws and the regionally accepted best-practices Be Whale Wise Guidelines. </p><p> Chapter three, <i>The effects of vessels on group cohesion and behavior of southern resident killer whales (Orcinus orca),</i> discusses research investigating changes in killer whale group cohesion in response to vessel density, distance and mode of operation. Future cetacean studies would benefit from using the equipment and methods presented here, especially in areas that are not conducive to land-based theodolite collected data.</p>

<p> Many school-aged children fear certain animals. Fear tends to make children worry and exhibit anxious behaviors, and this can negatively affect many aspects of their lives. Rachman (1977) speculated that some children might acquire fear through receiving negative verbal information. Few studies have examined whether positive verbal information can influence children's fear beliefs about bats. Based on Rachman's Theory on the Acquisition of Fear Behaviors this experimental research study examined whether positive verbal information might relate to decreasing fears about bats. One hundred and seventy-two participants in Grades 2 through 4 completed the Fear Beliefs Questionnaire (FBQ) and the Bat Attitude Questionnaire (BAQ) and then were randomized to either a positive verbal information treatment group or a control group. Both fear and bat attitude measures were administered to 2 groups of children across 3 time intervals. During Time 1, both groups filled out the FBQ and BAQ. Group 1 then received positive verbal information while Group 2 completed a maze. During Time 2, both groups again completed the FBQ and BAQ. One day later, Group 2 received the positive verbal information, and during Time 3, both groups again completed the FBQ and BAQ. MANCOVA results revealed a difference between FBQ and BAQ scores for both groups across all times. Group 1 showed no significant difference in FBQ and BAQ scores following positive information, and Group 2 only showed a significant difference in BAQ scores. The results of this study may have implications for social change in clinical practice with children experiencing fear of animals. This experimental study suggests that psychoeducational programs and psychotherapy addressing fears in children could be enhanced with the use of positive verbal information.</p>

<p> Understanding the variables that maintain reinforcer effectiveness has important implications for basic research to inform applied behavior analysis. The goal of the current study was to investigate the combined effects of rate of reinforcement and variability in duration and delay of reinforcement on within-session changes in operant responding in two experiments. In each experiment, Wistar rats (<i>Rattus norvegicus</i>) lever pressed for liquid sucrose on three fixed interval (FI) schedules of reinforcement. In Experiment 1, subjects lever pressed for liquid sucrose on either a constant or a varied duration of access to reinforcement. In Experiment 2, subjects were exposed to a constant or variable delay of reinforcement. Results showed two fundamental properties of behavior undergoing habituation. First, within-session decreases in responding were steeper (greater habituation) at higher rates of reinforcement than at lower rates. Second, within-session rates of responding declined more slowly (slower habituation) when access to the reinforcer was presented in a variable versus constant manner. Because habituation occurs for both ingestive and noningestive stimuli, the present study adds to the body of literature on habituation and can inform clinical practice on the variables that sustain operant behavior through varying the delivery of the reinforcer.</p>

<p> This dissertation is theoretical study of horse-human relationship, addressing the topics of communication, learning and cognition in the context of the cybersemiotic model developed by philosopher of science S&oslash;ren Brier. This study found significant gaps in the literature with respect to how horses and humans communicate and learn together, and is an attempt to develop an integral conceptual model grounded in communication and learning theory. </p><p> The overarching theoretical platform is the cybersemiotic model, which is a transdisciplinary research platform that addresses knowledge creation from an objective and subjective vision of reality. The center of knowledge in this model is semiosis, the sign system and spheres of signification through which living beings create meaning and make sense of the world. The cybersemiotic model is inclusive of non-human languaging systems, grounded in the biosemiotic view that extends sign systems to the life world of animals. The analysis of horse-human communication is performed using Bateson's theories of non-verbal communication and learning, based on the second-order cybernetic science view. Likewise, the topic of the role of inner life and consciousness in horse-human interaction is analyzed through the phenomenological, pragmaticist philosophy of Charles Sanders Peirce and his triadic conception of semiosis. </p><p> The results of this theoretical and philosophical exploration point to the need to begin constructing serious, scientifically grounded conceptual frames that can inform equestrian activities across a wide variety of disciplines such as competition and entertainment, leisure, horse training, and equine-facilitated psychotherapy/learning (EFP/L). These disciplines are fairly divided in their view of horses, especially when it comes to communication protocols, equine intelligence, and the use of a shared language to describe horse-human interaction. </p><p> Besides starting to lay theoretical groundwork for conceptualizing how horses and humans communicate and learn together, this dissertation also addresses the fundamental issue of personal safety and ethics in horse communities. The horse industry is a billion dollar industry in the U.S. and other Western nations, with most horses living in captivity in human-controlled environments. As the horse industry grows, so do the number of related accidents, making equestrian sports one of the most dangerous. An understanding of ethologically grounded communication principles is essential in ensuring greater safety for horse handlers and the wellbeing of horses. It is also key in addressing the larger question of ethics in the relationships of humans to non-human others and the ecology of the Earth at large.</p>