The fisher (Martes pennanti) is a medium sized member of the mustelid family that once roamed the forests of Washington and whose historic range in the western United States once spread throughout the northern Rocky Mountains, the Cascade and Coast Ranges, and the Sierra Nevada (Carroll, Zielinski, and Noss 1999; Powell 1993, Spencer et al. 2011). Due to pressures from trapping and habitat fragmentation, the abundance of the species in the western United States has decreased dramatically and is thought to be limited to several small, isolated populations. In 2008, fishers were reintroduced to the Olympic Peninsula; however, bobcat (Lynx rufus) predation in the first years is thought to have killed off a significant portion of the released fisher hindering their ability to establish a self-sustaining population (Lewis et al. 2011). Other studies in the western United States have shown that bobcats can be a dramatic force on small or isolated fisher populations. The coniferous forest of the southern Washington Cascades is the possible site of a release of currently extirpated fishers. My research examines the distribution of bobcats in the region and explores the implication this and the habitat variables of the area have for a future reintroduction of fisher. The workflow of the research was a stepwise process of: 1) surveying forested areas in the southern Washington Cascades for the presence and absence of bobcat and acquiring previously completed survey data 2) using a classification tree to model the correlation of bobcat presence or absence with forest variables and 3) applying these relationships to spatial analysis the creation of maps showing areas of high ranking fisher habitat. The classification tree modeled the correlation between the forest variables and the results of the surveys, which included 145 bobcat absence observations and 39 presence observations. The model highlighted a 95% probability of absence above 1,303 m in elevation, 73% probability of absence in areas under 1,303 m in elevation and with a tree diameter value under 43.45 cm, 57% probability of absence in areas between 1,070 m and 1,303 m in elevation and with a tree diameter value above 43.45 cm, and an 89% probability of bobcat presence in areas under 1,070 m in elevation with a tree diameter value above 43.45 cm. I applied an upper elevation limit of 1,676 meters as a threshold for suitable habitat and only considered habitat suitable in cells with a tree diameter above 29 cm. The three locations highlighted as the most suitable areas for reintroduction due to a large amount of the highest ranking habitat and the largest aggregations of suitable habitat cells were around the William O. Douglas Wilderness that straddles the border of the Gifford Pinchot National Forest (GPNF) and the Wenatchee National Forest, another location in the Norse Peak Wilderness northeast of Mount Rainier, and a third location in Indian Heaven Wilderness in the southern portion of the GPNF.

Winter conditions are believed to play an important role in the population dynamics of northern temperate stream fish, challenging the ability of fish to physiologically and behaviourally adapt. Climate change is predicted to increase both mean temperature and temperature fluctuations, especially during winter, leading to dynamic environmental conditions in terms of river ice production and flow. Therefore, knowledge about the winter ecology of stream fish is important for predicting and mitigating anthropogenic impacts on fish production in boreal streams. Stream salmonids are relatively active throughout winter, and behavioural responses to different winter conditions may be critical for survival. Yet, relatively little is known about overwintering behaviour of salmonids, particularly in streams with ice. In this doctoral thesis, I report the results from experimental field and laboratory studies on the behavioural ecology of juvenile salmonids under winter conditions. My results from the field show that salmonids grow more and use a broader range of habitats in the presence of surface ice than in its absence. Results from the laboratory experiments show that the presence of surface ice increases food intake rates, reduces stress and affects social interactions. These laboratory results may explain the positive effects of ice cover on growth that was found in the field experiment. Moreover, I show that drift-feeding ability is reduced at low temperatures, and that nocturnal drift foraging under winter conditions has a low efficiency. / Vinterförhållanden kan spela en avgörande roll för förekomsten av fisk i våra vattendrag. Laxfiskar, som till exempel lax, öring och harr, är vinteraktiva och måste därför anpassa sin fysiologi och sitt beteende till en miljö som karakteriseras av låga och föränderliga vattenflöden, liten tillgång på föda, kallt vatten, is och mörker. Trots att dessa anpassningar är avgörande för chansen att överleva vintern, vet man relativt lite om laxfiskars vinterbeteende, speciellt i vattendrag som täcks av is. I denna avhandling presenterar jag resultat från fält- och laboratoriestudier av laxfiskars beteende under vinterförhållanden och resultaten visar att närvaron av yttäckande is ökar tillväxt och födointag, minskar stress samt påverkar var fiskar uppehåller sig och hur fiskarna interagerar med varandra. Jag har också undersökt hur laxfiskars beteende i rinnande vatten påverkas av ljusintensitet och vattentemperatur i samband med födointag. Resultaten visar att den minskade dagaktiviteten som laxfiskar uppvisar på vintern medför en kostnad i form av försämrad förmåga att fånga byten. / Winter conditions are believed to play an important role in the population dynamics of northern temperate stream fish, challenging the ability of fish to physiologically and behaviourally adapt. Climate change is predicted to increase both mean temperature and temperature fluctuations, especially during winter, leading to dynamic environmental conditions in terms of river ice production and flow. Therefore, knowledge about the winter ecology of stream fish is important for predicting and mitigating anthropogenic impacts on fish production in boreal streams. Stream salmonids are active throughout winter, and behavioural responses to different winter conditions may be critical for survival. Yet, relatively little is known about overwintering behaviour of salmonids, particularly in streams with ice. This doctoral thesis focuses on the behavioural ecology of salmonids under winter conditions, and results from field and laboratory experiments show that the presence of surface ice increases food intake rates, reduces stress and affects social interactions, with effects on growth and habitat use. Moreover, drift-feeding ability is reduced at low temperatures, and nocturnal drift foraging under winter conditions has a low efficiency. / <p>Artikel 1 i avhandlingen som manuskript. Nu publicerad.</p>

For several years, the literature has discussed whether a country’s particular economic circumstances should be taken into account in competition law and policy design. This thesis discusses whether economic growth should be considered as the guiding principle for Latin American Emerging Economies’ competition law and policy design. It specifically explains why having economic growth as competition policy’s guiding principle makes a difference in choosing superior rules and standards, among the large range of efficient rules. In order to explain how economic growth as a guiding principle has an impact on competition policy design, this thesis studies whether the analysis and application of the prohibitions and standards of abuse of dominance in emerging Latin American economies are appropriate, and why, having regard to economic growth, a different approach might be justified. To engage in the study of such questions this thesis centres on the regulation of dominance and the law governing abuse of dominance, in particular on predatory pricing and excessive pricing. After a careful analysis of such institutions, an optimal rule for the regulation of pricing abuses in these emerging economies is proposed. Similarly, having regard to economic growth as the policy’s guiding principle, the mainstream standards on excessive pricing and price predation are evaluated and a different approach is found to be justified. It is concluded that economic growth should be the principle guiding Latin American emerging economies’ competition law and policy design and it is demonstrated that this will grant these economies policy soundness and identity.

Predation may be a key component of the unsuccessful restoration of the Eastern Oyster (Crassostrea virginica), a former keystone species in Chesapeake Bay. Here, I examine the polyclad flatworm Stylochus ellipticus and its potential role as an important predator of C. virginica. Using small-fragment size C. virginica specific DNA primers, oyster DNA was successfully detected in whole organisms homogenates of wild-caught S. ellipticus individuals. Of the 1,575 individuals tested, 68.1% tested positive, thus predation occurred. Predation did not appear to be affected by salinity or temperature; however, season did appear to have an effect on both predation and S. ellipticus abundance (p-value: <0.05). The findings also imply that S. ellipticus are highly mobile, entering the water column to reach hard substrate at various depths, whereas previous studies suggest otherwise. These findings are useful in the planning and management of oyster cultivation and restoration. Furthermore, this study outlines a method of diet study that may be more sensitive than traditional DNA-based techniques.

Channel catfish have pectoral spines that lock to defend against gape-limited predators such as largemouth bass. Previous work indicated that spines increase survival of channel catfish exposed to bass but did not determine whether bass avoid catfish if less dangerous species are available. We presented bass with channel catfish and two alternatives, bluegill and goldfish, and compared order of ingestion, ingestion time, percent of successful strikes, and time spent chasing each prey species. We also presented the three species in a jar study that standardized position in the water column as well as in a net-pen study. The order of ingestion was suggestive of a preference for goldfish, then bluegill and finally channel catfish. Handling time was greater for channel catfish, less for bluegill, and the least for goldfish. Fewer catfish were eaten when other prey were available. Bass appear to avoid channel catfish if alternative prey is available.

Key words: (Dugesia tigrina), ecology, bioindication, predation, Vltava, Prague The main goal of my thesis was the research of occurrence and ecology of planarians of the group Ttricladida in the Vltava River and some brooks flowing through the territory of Prague. The emphasis was given on the non-native North American species - Dugesia tigrina. The research can be divided into field surveys of population size and ecological requirements of planarians and a laboratory experiment, in which I have investigated the predation behavior of planarians. During my fieldwork, which took place from August 22th to November 11th 2009, I have found out that the Dugesia tigrina occurs only in the Vltava river, in six of the nine studied localities. During the research it was not found in the studied brooks. It chooses localities with a natural shoreline, deeper ground, rapid water and it lives in company of mainly Dugesia polychroa. It appeared at moderately polluted places. During the predation experiment, which ran from December 17th 2009 to October 20th 2010 at a temperature of 14 řC and triple repetitions in all mutual combinations of five planarian species, intraspecific cannibalism and frequent asexual reproduction of Dugesia tigrina was comfirmed. The experiment showed mainly preying of indigenous...

Seasonality influences life history through its effect on the availability of essential resources, with birds timing breeding to occur during peak food availability. Due to density-dependence, investment in breeding is determined largely by the seasonality of food availability, with an increased investment being traded-off against adult survival. A bird's mass acts as an index of a species' foraging environment, because a bird bases its foraging decisions on a trade-off between the risk of predation and the risk of starvation. Under constant predation risk a bird increases its mass as insurance against increased foraging unpredictability. In tropical savannahs day length and temperature remains relatively constant, and there is not a season of increased density-dependent mortality which acts across all species. Thus species have evolved a broad range of life history traits under the same environmental conditions, although how a species experiences seasonality depends largely on its foraging niche. This thesis shows that most savannah species varied their mass across the year, having a reduced mass in the non-breeding season which suggests that foraging remained predictable. Independent of gonad or egg growth they then increased their mass as they started to breed, with the timing of breeding coinciding with peak food availability. Across species in the same foraging niche mass acts as an index of breeding investment, with females increasing their mass more than males. While across species in different foraging niches an increased mass response was associated with higher adult survival, probably because breeding strategy and subsequently adult survival are governed by food limitation. This thesis shows that birds adaptively manage their mass during breeding and that mass is not a result of energetic stress, thus under constant predation risk a bird's mass is a result of foraging predictability as a function of competition for available food and investment in breeding.

Orientador: Laurence Marianne Vincianne Culot / Resumo: A seleção de dormitórios pelos primatas pode ser influenciada por diversos fatores, como a predação, termorregulação e defesa de território. Nosso objetivo foi investigar quais desses fatores influenciam a seleção de dormitórios pelos micos-leões-pretos e se há divergência nas características dos dormitórios entre uma floresta contínua e um fragmento. Estudamos dois grupos de mico-leões-pretos, um numa floresta contínua e um num fragmento na região do Pontal do Paranapanema, São Paulo, Brasil. Nós coletamos os dados sobre as características físicas dos dormitórios e das árvores disponíveis no habitat. Usamos testes de Mann-Whitney para comparar as características físicas dos dormitórios com as árvores disponíveis e Funções de Seleção de Recursos (RSF) para entender quais dessas características são mais importantes na escolha dos dormitórios. Os micos-leões-pretos usaram árvores mais altas, com menor número de conexões de copas e com um alto grau de cobertura de copa para dormir, quando comparado às árvores disponíveis. Os dormitórios usados pelo grupo da floresta contínua eram maiores, com as primeiras ramificações inferiores mais altas e com menor número de conexão de copas do que os dormitórios usados pelo grupo do fragmento. Nossos resultados evidenciam a presença de estratégias anti-predação pelos grupos de micos-leões-pretos, com o grupo da floresta contínua apresentando um processo de seleção de dormitórios mais refinado, no qual a seleção apenas de árvores que possuam ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Sleeping site selection by primates can be influenced by several factors, such as predation, thermoregulation and territorial defense. Our objective was to investigate which of these factors influence the sleeping site selection by black lion tamarins and if there is divergence in the characteristics of the sleeping sites between a continuous forest and a fragment. We studied two groups of black lion tamarins, one in a continuous forest and one in a small and isolated fragment in the Pontal do Paranapanema, São Paulo, Brazil. We collected data on the physical characteristics of the sleeping sites and available trees within the both habitats. We used Mann-Whitney tests to compare the physical characteristics of the sleeping sites with available trees and Resource Selection Functions (RSF) to understand which of these characteristics are most important in choosing the sleeping sites. Black lion tamarins used taller trees, with a fewer canopy connections, and a higher degree of canopy cover compared to the available trees. The sleeping sites used by the continuous forest group were larger, with the first lower ramifications higher and with fewer number of canopy connections than the sleeping sites used by the fragment group. Our results evidenced the presence of anti-predation strategies by both black lion tamarin groups, with the continuous forest group presenting a more refined sleeping site selection process, in which the selection of only trees with a larger set of character... (Complete abstract click electronic access below) / Mestre

The cues used by marine turtles to locate foraging areas in the open ocean are largely unknown though some species (especially the green turtle [Chelonia mydas], the loggerhead [Caretta caretta], and the leatherback [Dermochelys coriacea]) somehow locate areas of high productivity. Loggerheads can detect airborne odors, but a capacity to orient has not yet been investigated. In this comparative study, tethered loggerheads and leatherbacks were exposed to dimethyl sulfide (DMS) or food odors in a laminar flow of air. Turtles did not orient into the air current. Free-swimming loggerheads and green turtles were also exposed to air- or waterborne food (squid) odor plus a neutral visual stimulus. Both species showed increases in swimming activity and biting behavior to both stimuli. These results suggest that airborne odors are likely not used to locate distant areas, but that they are used in localized food searching efforts. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

The Argentine black and white tegu, Salvator merianae, is a nonnative species that has invaded parts of Florida. The potential impacts of this species on native Florida wildlife are not yet known. This study looks at the stomach contents of 169 S. merianae captured between 2011 and 2013 in south Florida to infer potential impacts of S. merianae and spatial or seasonal shifts in diet. Analysis of 169 GI tracts showed that S. merianae is an omnivorous, terrestrial forager with a broad dietary range which includes insects, fruits, plants, snails, crayfish, carrion, birds, small mammals, turtles, snakes, lizards, frogs and eggs. S. merianae diet composition varied with capture habitat, the fattest tegus were collected from disturbed/agricultural areas and these samples contained, primarily, gastropods and insects. Tegu dietary habits threaten local endangered and state listed species such as the American crocodile, Crocodylus acutus, and the Cape Sable seaside sparrow, Ammodramus maritimus mirabilis. Dedicated funds and efforts need to be focused on this species to limit its further spread and future impact on native species. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection