As charismatic megafauna and a flagship species, African elephants (Loxodonta africana) are vital to the African tourist economy. Conversely, high levels of wildlife tourism can induce behavioral shifts that push desired animals into less frequented areas and disrupt natural behaviors. In order to examine this trade-off, tourism levels and African elephant behaviors were studied in Zambezi National Park (ZNP) near Victoria Falls, Zimbabwe. Over the course of 14 weeks, in-person observations and camera traps in ZNP were used to collect geographic, demographic, and behavioral data from elephant sightings. As a proxy for human presence, geo-locational data were collected for each vehicle sighted in ZNP. These data of vehicles and elephants were mapped in ArcGIS to show a visual representation of their spatial relationship and identify high density and hotspot locations. Analyses from physical observations found that elephants were more frequently sighted in the park region with less vehicle traffic, as expected, but surprisingly also expressed more vigilance behaviors in that region. These results imply that elephants in high traffic regions become accustomed to vehicles but still avoid them when possible. Analyses from camera trap data revealed that only two of the six waterholes monitored had inversely related elephant and human presence, as predicted. There was no clear relationship between elephant and human presence. Future studies should account for habitat type differences in behavioral observations and compare elephant waterhole use in more heavily visited parks.

The contagious nature of the black-tailed prairie dog (Cynomys ludovicianus) jump-yip display may provide information to signalers and receivers regarding the vigilance of neighbours. Videotaping jump-yip bouts and the behaviour of both bout initiators and respondents within those bouts provided evidence that: 1) individuals became vigilant immediately following jump-yip production, but exhibited minimal changes in their immediate post-jump-yip behaviour with changes in the characteristics of the preceding bout, 2) bout initiators spent more time actively foraging and exhibited vigilance behaviours less frequently with greater levels of response in the preceding jump-yip bout, 3) respondents spent more time actively foraging and less time vigilant following bouts with greater response. These results suggest that black-tailed prairie dogs base behavioural decisions at least in part on the characteristics of their jump-yip bouts and thus the jump yip display may provide information about the vigilance of group members. / October 2007

Amphibian decline is a major concern worldwide, and a lack of basic ecological and life history information for many species significantly limits our ability to evaluate the degree and possible causes of such declines, and to develop effective conservation strategies for threatened and endangered species. Not only is there a shortage of adequate long-term datasets necessary for robust analyses of population variability, but the elusive nature and obscure microhabitats of many species make it difficult to collect even the most basic natural history data. In a series of observational and experimental studies, I employed both traditional and novel ecological methodologies to examine environmental correlates of temporal population variability, foraging ecology and anti-predator behavior in endangered Barton Springs Salamander (Eurycea sosorum) from Austin (Travis County), Texas. Though headwater springs are typically thought of as habitats with relatively stable environmental conditions, I discovered that E. sosorum population abundance was strongly influenced by periodic extremes of rainfall that affect cycles in spring flow rates, water temperature, and other physico-chemical variables. I also found that population dynamics in E. sosorum are highly consistent with those expected for organisms with a storage effect life-history strategy, in which a few long-lived females capable of high fecundity and prolonged survival in subterranean habitat during adverse environmental conditions may be sufficient for population persistence. In addition, juveniles may use subterranean habitat as a thermal refuge. Using stable isotope analyses and macroinvertebrate prey censuses, I determined that at the population level, adult E. sosorum exhibits high electivity for planarian flatworms (Dugesia sp.). This would not have been detectable using traditional methods of dietary analysis such as stomach or fecal content analysis because Dugesia are soft-bodied animals. Additionally, stable isotope analyses revealed that adult E. sosorum exhibits inter-individual diet variation and is capable of diet switching. Finally, I discovered that anti-predator behavior in E. sosorum is influenced more strongly by visual and bioelectric cues from potential predators, but not olfactory cues. This is the first known demonstration of anti-predatory response mediated only by bioelectric stimuli in an amphibian, and one of very few to observe this phenomenon among aquatic vertebrates. / text

Antipredator defenses are ubiquitous in aquatic ecosystems. In the widely studied Chaoborus-Daphnia predator-prey system, Daphnia elicit a variety of phenotypically plastic responses to Chaoborus including: morphological, life history, and behavioral responses. While these inducible defenses benefit the prey, metal contaminants have been shown to interfere with chemosensory functions, thereby inhibiting antipredator defenses and decreasing survivorship. However, in lakes with a history of metal contamination, such as Kelly Lake in Sudbury, Ontario, there is evidence to suggest that Daphnia may have adapted to high, ambient copper concentrations. Using seven distinct Daphnia clones that were hatched from resting eggs from Kelly Lake, we examined morphological and life history traits when clones were exposed to either a nominal concentration of copper, kairomone, or a combination of both. As expected, clones displayed a variety of inducible responses in both kairomone-control and kairomone-copper treatments, which was attributed to genetic variability. Expected trade-offs in life history traits were not always observed, suggesting that inducible traits may be coupled. Furthermore, in contradiction to life history theory, one clone exhibited both increased somatic growth and increased reproductive output, indicating that clones likely adopted adaptive strategies to stressors rather than elicitng trade-offs in traditional traits. Our results indicate that environmentally relevant copper concentrations do not inhibit the induction of antipredator defenses in Daphnia from Kelly Lake, and we conclude that Kelly Lake Daphnia have developed an adaptive tolerance to copper. Adaptation to copper contamination may have implications for resilience in natural Kelly Lake populations. / Thesis (Master, Biology) -- Queen's University, 2012-04-03 19:33:59.137

The contagious nature of the black-tailed prairie dog (Cynomys ludovicianus) jump-yip display may provide information to signalers and receivers regarding the vigilance of neighbours. Videotaping jump-yip bouts and the behaviour of both bout initiators and respondents within those bouts provided evidence that: 1) individuals became vigilant immediately following jump-yip production, but exhibited minimal changes in their immediate post-jump-yip behaviour with changes in the characteristics of the preceding bout, 2) bout initiators spent more time actively foraging and exhibited vigilance behaviours less frequently with greater levels of response in the preceding jump-yip bout, 3) respondents spent more time actively foraging and less time vigilant following bouts with greater response. These results suggest that black-tailed prairie dogs base behavioural decisions at least in part on the characteristics of their jump-yip bouts and thus the jump yip display may provide information about the vigilance of group members.

The contagious nature of the black-tailed prairie dog (Cynomys ludovicianus) jump-yip display may provide information to signalers and receivers regarding the vigilance of neighbours. Videotaping jump-yip bouts and the behaviour of both bout initiators and respondents within those bouts provided evidence that: 1) individuals became vigilant immediately following jump-yip production, but exhibited minimal changes in their immediate post-jump-yip behaviour with changes in the characteristics of the preceding bout, 2) bout initiators spent more time actively foraging and exhibited vigilance behaviours less frequently with greater levels of response in the preceding jump-yip bout, 3) respondents spent more time actively foraging and less time vigilant following bouts with greater response. These results suggest that black-tailed prairie dogs base behavioural decisions at least in part on the characteristics of their jump-yip bouts and thus the jump yip display may provide information about the vigilance of group members.

Made available in DSpace on 2015-03-26T13:30:46Z (GMT). No. of bitstreams: 1 texto completo.pdf: 596898 bytes, checksum: a54e884db6b018e150d389984ba546eb (MD5) Previous issue date: 2013-02-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / As plantas possuem mecanismos de defesa contra os ataques dos herbívoros. Estes mecanismos podem afetar diretamente os herbívoros, por exemplo, plantas podem produzir metabólitos secundários que reduzem ou param o desenvolvimento dos herbívoros, ou indiretamente por meio de interação com os inimigos naturais dos herbívoros. Plantas atacadas podem produzir compostos voláteis atrativos para inimigos naturais. Essas pistas voláteis são indicativas da presença das presas e são importantes para o sucesso do forrageamento de inimigos naturais. Por outro lado, herbívoros também são capazes de perceber pistas indicativas da presença de predadores e usá-las para evitar locais com risco de predação. Comportamentos antipredação aumentam a sobrevivência das presas, no entanto também podem gerar custos. No presente trabalho, foram estudados os comportamentos de forrageamento e antipredação no sistema do tomateiro com os ácaros fitófagos Tetranychus urticae e Tetranychus evansi, e os ácaros predadores Phytoseiulus longipes e Phytoseiulus macropilis. Ambos os predadores foram capazes de reconhecer pistas de tomateiros infestados mostrando preferência por plantas infestadas por T. evansi e T. urticae em relação a plantas limpas, mas não mostram preferência entre as presas. Estes predadores se alimentam de ambas as presas, no entanto P. macropilis não completa seu ciclo de vida se alimentando apenas de T. evansi. Assim, para P. longipes ambasas presas como fonte de alimento adequada, mas para P. macropilis T. evansi é um alimento de qualidade inferior. É possível que P. macropilis não seja capaz de distinguir pistas oriundas de tomateiros infestados por T. evansi ou T. urticae. Adicionalmente, T. evansi é capaz de perceber a presença de P. longipes e P. macropilis, e foi capaz de reconhecer pistas oriundas desses predadores e mudar seu comportamento de acordo com a espécie de predador e da escala espacial. Tetranychus evansi tentou escapar por mais vezes nos discos foliares com pistas de ambos predadores, tendo também redução no tempo de alimentação. No entanto, também há custos associados a estes comportamentos: T. evansi apresentou redução na taxa de oviposição nos discos foliares com pistas de P. longipes, mas não com pistas de P. macropilis, provavelmente por que este predador não é perigoso para T. evansi como P. longipes é. Em uma escala espacial maior (hexágono de plantas) onde os ácaros caminhariam sobre substrato tendo de percorrer longas distâncias e perceber pistas com intensidade provavelmente mais fraca, T. evansi não evitou plantas com predadores. Todos os tomateiros estavam infestados com coespecíficos que produzem grande quantidade de teia, possivelmente T. evansi não evitou plantas com predadores pela possível proteção conferida pela teia. Concluindo, os predadores P. longipes e P. macropilis são capazes de usar pistas de plantas atacadas para localizar suas presas T. evansi e T. urticae, mas não as distinguem. Tetranychus evansi é capaz de perceber a presença de ambos predadores e mostrar comportamento antipredação de acordo com o perigo oferecido pelo predador e a escala espacial envolvida. / Plants have mechanisms to defend themselves against herbivore attacks. These mechanisms may affect the herbivores directly, for example, plants can produce secondary metabolites that reduce or stop the growth of the herbivores, or indirectly by interacting with the natural enemies of the herbivores. Upon herbivore attack, plants are known to produce volatiles that are attractive to natural enemies. These volatile cues are indicative of the presence of prey, and are important for the foraging success of the natural enemies. In return, herbivores are able to recognize cues associated with the presence of predators and use these to avoid patches with predators. Such antipredator behaviour increases the survival of the prey; however, it may also have costs. Here, we studied the antipredator and foraging behaviour of the spider mites Tetranychus urticae and T. evansi, the predatory mites Phytoseiulus longipes and P. macropilis on tomato plants. Although the predators feed on both prey, P. macropilis can not complete its life cycle feeding only on T. evansi. Thus, for P. longipes both prey are adequate food sources, but T. evansi is a bad food source for P. macropilis. Both predators were able to recognize cues from infested or uninfested plants, showing preference for plants infested by T. evansi or T. urticae compared to uninfested plants, but they did not show a preference for plants with either of the two prey.It is possible that P. macropilis are not able to discriminate cues from tomato plants infested by these prey. Additionally, T. evansi can perceive the presence of P. longipes and P. macropilis. This herbivore was able to recognize cues from these predatory mites and to change its behaviour according to the species of predator and spatial scale. The spider mite tried to escape more often from leaf discs with predator cues, and also reduced its time spent feeding. However, there were also costs associated with this antipredator behaviour: T. evansi showed a decrease in oviposition rate on leaf discs with cues from P. longipes, but not with cues from P. macropilis, probably because this predator is not as dangerous to T. evansi as P. longipes is. At a larger spatial scale (hexagon of plants), where the spider mites walked on substrate soil and in all directions, T. evansi did not avoid plants with conspecific and predators; probably it perceived the presence of conspecific that produce high density of web which can protect it against predation. Concluding, the predatory mites P. longipes and P. macropilis can use cues from attacked plants to locate T. evansi and T. urticae, but do not discriminate between these two prey. In turn, T. evansi can perceive the presence of these predators, showing antipredator behaviour towards dangerous and harmless predators, according to the spatial scale.

My study was aimed to describe the antipredator behaviour of Barred Warbler against five avian mounted dummies differing in the level of threat they represent for the Barred Warbler: Eurasian Sparrowhawk (Accipiter nisus), Eurasian Jay (Garrulus glandarius), Black-billed Magpie (Pica pica), Red-backed Shrike (Lanius collurio), and Domastic Pigeon (Columba livia f. domestica) using the experiments carried in the vicinity of the nests with fledglings of Barred Warbler. The next goal of my study was to discover the relationship between the Barred Warbler and the Red-backed Shrike nesting together.

In previous studies with stuffed dummies, we found interesting difference in nest defence of Red-Backed Shrike (Lanius collurio) against two similar nest predators: Jay (Garrulus glandarius) and Magpie (Pica pica). Jay was attacked very intensively, whereas Magpie almost wasn´t hited and Shrikes seemed to keep in cover. Here, I describe the antipredation behavior of the Red Backed Shrike against another stuffed corvids presented closely to Shrikes nests: Jay (Garrulus glandarius), Common Nutcracker (Nucifraga caryocatactes), Rook (Corvus frugilegus), Crow (Corvus corone) and Raven (Corvus corax). I found Jay and Nutcracker to be attacked by Shrikes very strongly, whereas Rook, Crow and Raven were attacked rarely (Shrikes only flied around them or sit at a distance, watching the dummy, sometimes accompanied with alarm-calls). Shrikes response is affected mainly by kind of predator, by age of youngs and by quality of concealment of nest. More - www.mn.ic.cz

Diel rhythms of physiology and behaviour are present in virtually all taxa examined to date. However, few studies have rigorously assessed the adaptive value of physiological and behavioural rhythms in animals. We laid the groundwork for an assessment of the adaptive rhythm hypothesis by assaying diel rhythms of foraging and antipredator behaviour in the trashline orb-weaver Cyclosa turbinata (Araneae: Araneidae). When confronted with a predator stimulus in experimental arenas, C.turbinata showed thanatosis behaviour more frequently and for longer durations during the day. However, assays of antipredator response within webs revealed more complex diel patterns of avoidance behaviours and no pattern of avoidance behaviour duration. A preliminary assay of prey capture behaviour suggested that C.turbinata also shows nocturnal patterns of foraging aggression. A refined foraging experiment, in which we randomized prey stimulus frequency, found that time of day and spider ID strongly predicted the likelihood of showing prey capture behaviour. Only spider ID predicted latency to attack the prey stimulus despite low individual repeatability (r= 0.10). These results support our prediction that C.turbinata modulate foraging aggression over the diel cycle, but we found no evidence of a trade-off between foraging behaviour and predator vigilance. However, overall patterns of vigilance may be masked by diel changes in antipredator strategies that correspond to fluctuations in the relative abundances of predator types.