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Behavioral Differences Between Native And Exotic Invertebrate Prey Affect Susceptibility To Predation By A Native Amphibian Predator
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Book Synopsis Behavioral Differences Between Native and Exotic Invertebrate Prey Affect Susceptibility to Predation by a Native Amphibian Predator by : Zachary Cava
Download or read book Behavioral Differences Between Native and Exotic Invertebrate Prey Affect Susceptibility to Predation by a Native Amphibian Predator written by Zachary Cava and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Invasive species threaten global biodiversity via mechanisms that include altering the dynamics and structure of native food webs. Whereas much research has focused on how exotic species respond to native predators, less is known about how native predators are affected by invasive prey. Here I investigate the response of a rare and threatened native predator-the Eastern Hellbender (Cryptobranchus alleganiensis) to a high-profile invasive crayfish species, Orconectes rusticus. Hellbenders have declined throughout much of their range, and although the potential for exotic predators (i.e. sport fish) to negatively impact C. alleganiensis has been addressed, effects of exotic prey on hellbender populations are unknown. Crayfish are an important food resource for C. alleganiensis; however, some speculate the large and aggressive O. rusticus may be unpalatable to hellbenders in regions where these species have not historically co-occurred. The primary objective of this study was to determine how C. alleganiensis responds to a native prey species (Orconectes obscurus), relative to an exotic prey species (O. rusticus). Specifically, I tested to see if hellbenders discriminated between crayfish species using chemoreception, then I analyzed behavioral interactions among hellbenders and crayfish during video-recorded trials, and lastly, I assessed hellbender selectivity of crayfish prey during overnight feeding trials. Cryptobranchus alleganiensis generally showed a preference for the scent of native crayfish, and were more likely to strike at native crayfish. However, more invasive crayfish were consumed during overnight feeding trials. This discrepancy apparently results from differences in avoidance behavior between prey species; native crayfish (O. obscurus) exhibited superior avoidance abilities relative to the exotic O. rusticus. Thus, during biotic invasions, food preferences of native predators may be superseded by differences in antipredator behavior of prey.
Book Synopsis Personality and Predation in a Changing World by : Chelsea A. Blake
Download or read book Personality and Predation in a Changing World written by Chelsea A. Blake and published by . This book was released on 2016 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interaction between predators and prey is one of the driving forces that shape not only animal behavior, but also the evolution and ecology of organisms. However, predator-prey interactions are now taking place in an unprecedented and rapidly changing world, as humans introduce new species and alter habitat conditions. Thus examining the anthropogenic introduction of novel predators is key to the contemporary study of behavioral ecology. Further, not all individual animals behave the same way within the same species or population, thus it is important to also assess behavior at the level of the individual. Individual behavioral types, or "personalities" of animals can have far-reaching implications for their ecology. Here I have explored predator-prey interactions in the context of changing environments from the perspective of individual-level variation to provide novel insights into species interactions. I have found that the personality of prey can affect how they fare with predators, but that the effect depends on which predator species they face. Additionally, I have shown that although behavioral type is important in predator interactions, it does not affect whether prey are able to recognize a novel predator. I have also explored how physical antipredator characteristics of individuals might relate to their behavioral type. I have found that although physical traits are not necessarily inherently correlated with behavioral traits, altering the physical condition of an individual can affect their behavioral traits. Ultimately, my work contributes to the understanding of how prey personality could interact with introduced predators to either aid or hinder the survival of native species.
Download or read book The Zoological Record written by and published by . This book was released on 1870 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Native Prey Versus Nonnative Predators by : Stephanie A Kraft
Download or read book Native Prey Versus Nonnative Predators written by Stephanie A Kraft and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fish are one of the most imperiled groups of vertebrates worldwide. Threats to fish fall into one of four general categories: physical habitat loss or degradation, chemical pollution, overfishing, and nonnative species introductions. Nonnative predatory fish often have a devastating impact on native prey, especially with endemic fish, whose restricted distribution and often limited evolutionary history with predators make them particularly susceptible to nonnative predators. One reason nonnative fish are often so efficient predators is that the native fish do not recognize the predator as a threat. Although many studies have examined the role of predator odor recognition, no fish have been shown to possess an innate recognition of the odor of predators unless they share a close co-evolutionary history. Many fish learn to identify novel predators through exposure to a predator's odor in conjunction with a conspecific alarm cue. Alarm cues are substances that are stored in the epidermis of many fish and are released when skin cells are broken. Exposure to novel predator odor in conjunction with alarm cue does not necessarily require a fish to survive a close encounter with a predator to be able to learn to recognize the predator. Here I show that it is possible to train hatchery-raised fish (June sucker, Chasmistes liorus) to recognize a nonnative predator odor (largemouth bass, Micropterus salmoides) through exposure to the odor of a predator that has eaten June sucker. I also show that this training can translate into higher survival in subsequent encounters with predators. I propose that training hatchery-raised fish prior to stocking may increase survival of hatchery-raised fish through anti-predator behavior.
Book Synopsis Antipredator Defenses in Birds and Mammals by : Timothy M. Caro
Download or read book Antipredator Defenses in Birds and Mammals written by Timothy M. Caro and published by University of Chicago Press. This book was released on 2005-09 with total page 609 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tim Caro explores the many & varied ways in which prey species have evolved defensive characteristics and behaviour to confuse, outperform or outwit their predators, from the camoflaged coat of the giraffe to the extraordinary way in which South American sealions ward off the attacks of killer whales.
Book Synopsis Predator-prey Interactions Between Hellbenders (Cryptobranchus Alleganiensis Alleganiensis and C.A. Bishopi) and Native and Nonnative Fishes by : Brian G. Gall
Download or read book Predator-prey Interactions Between Hellbenders (Cryptobranchus Alleganiensis Alleganiensis and C.A. Bishopi) and Native and Nonnative Fishes written by Brian G. Gall and published by . This book was released on 2008 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: The introduction of nonnative fishes often results in the local extinction of native amphibians due to a lack of evolutionary history and therefore, minimally-adapted antipredator behaviors toward the introduced fishes. Populations of hellbenders (Cryptobranchus alleganiensis) in Missouri have declined considerably since the 1980's, coinciding with a rapid increase in trout introductions for recreational angling. I examined hellbender and fish predator-prey interactions by: (1) examining the foraging behavior of predatory fishes in response to a hellbender secretion; (2) comparing the number of secretion and control-soaked food pellets consumed by trout; and (3) comparing the response of larval hellbenders to chemical stimuli from introduced (trout) and native fish predators. Brown trout, walleye and large banded sculpin respond to hellbender secretions with increased activity while small banded sculpin responded by decreasing activity. In addition, brown trout ingested more hellbender secretion-soaked food pellets than control pellets, while rainbow trout expelled secretion-soaked food pellets. Finally, larval hellbenders exhibited weak fright behavior in response to chemical stimuli from nonnative trout relative to their responses to native predatory fish stimuli. These combinations of responses indicate that predation by nonnative fishes may be a plausible hypothesis for the decline of hellbender populations in Missouri.
Book Synopsis Predator-prey Interactions in the San Marcos Salamander (Eurycea Nana) by : Drew R. Davis
Download or read book Predator-prey Interactions in the San Marcos Salamander (Eurycea Nana) written by Drew R. Davis and published by . This book was released on 2012 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Predation is a strong, influential force in most ecological communities. Inappropriately responding to predators typically results in the direct consumption of prey individuals. In addition to responding appropriately to predators in order to survive these encounters, prey individuals are under selection to minimize the costs associated with responding. These costs may reduce the overall fitness of prey individuals as time spent responding to predators is time not spent increasing fitness through activities such as foraging or reproducing. As such, prey individuals should optimize their responses in order to survive encounters with potential predators as well as to minimize the costs associated antipredator behaviors. The introduction of novel predators into many environments has contributed to the decline in amphibian populations. Often, amphibians lack the ability to recognize these novel predators, and therefore, either do not respond or respond inappropriately to them. One such species which may be negatively affected by introduced predators is the San Marcos salamander (Eurycea nana). Eurycea nana is a federally threatened, fully aquatic salamander endemic to the headwaters of the San Marcos River. Currently, a diverse assemblage of native and introduced fish predators is present in the San Marcos River. While prior studies have helped to understand some aspects of how these salamanders respond to native and introduced predators, the role of predator generalization has yet to be explored. I found that E. nana can generalize its response to novel predators, as long as there are still similarities between these novel predators and predators which they recognize. Additionally, I have examined a stress hormone, corticosterone, to further characterize differences in the way E. nana responds to native and introduced fish predators. Differences in the way E. nana responds to native and introduced predators suggest that introduced predators may be causing a muted or diminished response. Differences in the temporal variation in risk of predation may be driving these differences, because introduced predators are highly abundant and may be frequently encountered.
Book Synopsis Amphibians of North Africa by : Daniel Escoriza
Download or read book Amphibians of North Africa written by Daniel Escoriza and published by Academic Press. This book was released on 2019-03-16 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: Amphibians of North Africa is a comprehensive compilation of available data on the amphibians and reptiles found in various ecosystems across North West Africa and parts of the Mediterranean region. It is essential to identifying and understanding the ecological role of regional herpetofauna and its conservational importance. It examines the biological origins and diversity of amphibians in North Africa, along with their diverse ecosystems, including deserts, grasslands and subtropical forests. The book features detailed descriptions of the adult and larvae stages of species, such as the North African fire salamander, the common painted frog, Brongersma's toad and the Mediterranean tree frog. This book is a vital resource for herpetology and ecology students and researchers, helping them identify, understand and conserve these amphibians and reptiles in their various habitats across the North African and Mediterranean regions. - Presents the only book on research and species recognition of North West African and Mediterranean amphibians and reptiles in all life phases - Provides novel, iconographic material about little-known species - Features helpful visuals, including ink-drawings, photographs of adult and larvae stages, habitat photographs and distributional maps
Book Synopsis Factors Mediating the Distribution and Impact of the Non-native Invertebrate Predator Bythotrephes Longimanus by : Anneli M. Jokela
Download or read book Factors Mediating the Distribution and Impact of the Non-native Invertebrate Predator Bythotrephes Longimanus written by Anneli M. Jokela and published by . This book was released on 2013 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Predicting the impacts of non-native species remains one of the greatest challenges to invasion ecologists. Because of their insularity, freshwater systems are particularly vulnerable to invasions, especially from non-native predators. The research in this thesis explores the role of abiotic and biotic factors in mediating the distribution and impact of Bythotrephes longimanus, a predatory cladoceran that has been introduced to freshwater systems in North America. Although the general impacts of this invasion have been documented, little is known about the factors that modulate them. Using a combination of field surveys and experiments, I tested several hypotheses concerning the influence of interactions with native species, as well as the role of heterogeneity in the light environment, in mediating the impact of Bythotrephes. Results demonstrated that biotic resistance by native macroinvertebrate predators does not play a limiting role in the establishment success of Bythotrephes. However, the within-lake distribution of Bythotrephes was influenced by these macroinvertebrates, suggesting that the native predator context matters when trying to understand the impacts of non-native predators. This was demonstrated with a mesocosm experiment in which the impact of Bythotrephes was constrained by the native Chaoborus larvae. In terms of the abiotic environment, in situ feeding experiments demonstrated that refuges from impact could exist for some prey taxa, as the outcome of predation by Bythotrephes was dependent on light availability and some prey taxa were more successful at evading predation under low light conditions. Finally, results show that adaptive behaviour by prey is also an important determinant of impact, as migrating Daphnia can escape predation effects by Bythotrephes. The combination of light-limited predation and a shallow distribution by Bythotrephes selects for prey that occupy relatively deeper positions during the day. As a whole, this research highlights the importance of complex interactions in mediating the impact of Bythotrephes and may help to explain some of the variation that has been documented among invaded lakes. A better understanding of these complex interactions can improve our ability to anticipate impacts as Bythotrephes continues to spread, as well as provide insight on some of the long-term effects following invasion.
Book Synopsis Sterile Insect Technique by : Victor A. Dyck
Download or read book Sterile Insect Technique written by Victor A. Dyck and published by CRC Press. This book was released on 2021-01-06 with total page 1493 pages. Available in PDF, EPUB and Kindle. Book excerpt: The sterile insect technique (SIT) is an environment-friendly method of pest control that integrates well into area-wide integrated pest management (AW-IPM) programmes. This book takes a generic, thematic, comprehensive, and global approach in describing the principles and practice of the SIT. The strengths and weaknesses, and successes and failures, of the SIT are evaluated openly and fairly from a scientific perspective. The SIT is applicable to some major pests of plant-, animal-, and human-health importance, and criteria are provided to guide in the selection of pests appropriate for the SIT. In the second edition, all aspects of the SIT have been updated and the content considerably expanded. A great variety of subjects is covered, from the history of the SIT to improved prospects for its future application. The major chapters discuss the principles and technical components of applying sterile insects. The four main strategic options in using the SIT — suppression, containment, prevention, and eradication — with examples of each option are described in detail. Other chapters deal with supportive technologies, economic, environmental, and management considerations, and the socio-economic impact of AW-IPM programmes that integrate the SIT. In addition, this second edition includes six new chapters covering the latest developments in the technology: managing pathogens in insect mass-rearing, using symbionts and modern molecular technologies in support of the SIT, applying post-factory nutritional, hormonal, and semiochemical treatments, applying the SIT to eradicate outbreaks of invasive pests, and using the SIT against mosquito vectors of disease. This book will be useful reading for students in animal-, human-, and plant-health courses. The in-depth reviews of all aspects of the SIT and its integration into AW-IPM programmes, complete with extensive lists of scientific references, will be of great value to researchers, teachers, animal-, human-, and plant-health practitioners, and policy makers.
Book Synopsis Non-consumptive Effects at the Intersection of Climate Change, Invasive Species, and Temporal Variation by : Jason Scott Sadowski
Download or read book Non-consumptive Effects at the Intersection of Climate Change, Invasive Species, and Temporal Variation written by Jason Scott Sadowski and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Predators have large effects on their prey and in turn the ecosystems that they inhabit. The very act of hunting and consuming prey changes prey densities and the interaction rates of prey with other species. But, predators are also known to have strong fear effects on their prey caused by the predator’s presence in the environment. There can be a few different mechanisms for these fear effects such as the expression of antipredator behavior (e.g., hiding) or the growth of antipredator defenses (e.g., spines). These mechanisms in turn influence prey growth and reproduction leading to further effects through the community at large. While the chapters of my dissertation look at different questions and use different methods, they are all united in their attempt to understand the factors that could modify these fear effects. Specifically, my dissertation examines how fear effects are modified by climate change, invasive species, and temporal variation. The first chapter examines how climate change could interact with introduced predator species to create novel fear effects. The presence of native nonlethal predators is known to change prey behavior, but introduced predators may not be recognized by native prey. In theory, prey may not have coevolved with the chemical cues or behavior of an introduced predator. At the same time, prey are also constrained in their behavior by the environment. Climate change induced increases in air and water temperature may affect prey metabolism and thus the abilities of prey to respond to predators, especially in marine ectotherms. I measured how the growth rates of an intertidal snail (Acanthinucella spirata) changes in the presence of nonlethal native (Romaleon antennarium) or non-native (Carcinus maenas) crabs under elevated temperatures in both field and lab experiments. Across my experiments introduced crabs induce as great or greater reductions in snail growth than native crabs under ambient conditions; but, under warmer conditions these patterns switch such that native crabs induce greater reductions in snail growth than introduced crabs. I then linked these patterns to how effectively each predator can attack small or large snails. In this case, native crabs can attack snails of all sizes, whereas the introduced crabs are more effective at the smaller size classes. Taken together, this chapter indicates that native snails are more likely to grow into larger size classes when the introduced crab is present at warmer temperatures, and may consider the introduced crab to be less of a threat at those temperatures. The second chapter links a specific mechanism of fear effect, antipredator behavior, to qualities of the predator. I developed a food chain model where predators eat prey and prey in turn eat a resource. Both predators and prey consumed their food at a rate dependent on how fast they move through the environment such that faster consumers encounter food items at a faster rate. Prey respond to increases in predator abundance by hiding and thereby slowing their average movement rates. This behavior creates a tradeoff between hiding and foraging because slowing reduces the prey’s rate of finding and consuming resources. I modeled two different types of communities, one with fast-moving “mobile” predators and the other with slow-moving “sit-and-wait” predators. Antipredator behavior was ineffective against mobile predators, but was highly effective against sit-and-wait predators. Antipredator responses to sit-and-wait predators allowed prey to increase in abundance as resources increased, whereas antipredator responses to mobile predators had no effect. Antipredator responses to sit-and-wait predators eliminated population cycles in the community, while antipredator behavior to mobile predators again had no effect. Overall, how predators forage is an important, previously unexamined aspect for both predator-prey cycles and prey abundance. In the third chapter, I examined how changing the temporal pattern of predation risk influences the prey’s foraging rate. Previous research on temporal variation in risk indicates that when prey are exposed to longer risk periods, they reduce their foraging rates. However, whether the distribution of these risk periods has an effect independent of total exposure time is unexamined. For example, multiple short risk periods may have a greater effect than one long risk period even if the total amount of time is equivalent. I developed a model of prey growth and prey foraging that incorporates a temporally variable predator and tested this model using a laboratory experiment. The experiment measured how a marine snail’s (Nucella ostrina) growth and foraging rate on barnacles (Balanus glandula) changes in response to crab predators (Cancer productus). Over 8 weeks, snails were exposed to predators for 100% of the time, 50% of the time or 0% of the time. I used two 50% treatments and exposed snails to crabs either every other week (high frequency), or for 4 weeks in a row (low frequency). Both my model and my experiment indicated that prey reduce their growth and foraging under high frequencies of risk. Moreover, when snails were exposed to high frequencies of risk, they ate less during both safe and risky periods, suggesting that this risk regime shifted the snail’s perception of background risk. Therefore, the effects of high frequency risk are intrinsically different from low frequency risk even when the total amount of exposure time is the same. The prey’s capacity to remember previous risk periods is likely an important component for further understanding the effects of temporally variable predators.
Download or read book Bibliography of Agriculture written by and published by . This book was released on 1996 with total page 2376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Metabolic, Physiological, and Behavioral Responses of Prey to Predation by : Richard Trone
Download or read book Metabolic, Physiological, and Behavioral Responses of Prey to Predation written by Richard Trone and published by . This book was released on 2015 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Predators are known to cause prey to alter their morphology, life history or behavior in ways that reduce the likelihood of the prey being consumed by the predator. Seldom considered, however, are the consequences of predators on internal morphology (e.g., gut length) or physiology of prey. Such consideration is important because these traits likely affect prey growth and could explain why prey often grow more slowly in the presence of predators. Furthermore, a history of exposure to predators may alter how strongly visual or chemical signals from predators affect prey physiology and behavior. I raised larval frogs in artificial ponds that either lacked or contained a caged fish predator and assessed whether rearing environment affected prey gut length, morphology, behavior, and metabolic rate. I also assessed whether the rearing environment affected the metabolic and behavioral response of larval frogs to either short-term visual or chemical signals from fish by measuring the metabolism and behavior of predator naïve and predator exposed larval frogs when exposed to short-term visual and/or chemical signals from fish. Tadpoles raised with predators had shorter guts but long-term predator exposure had no effect on the metabolic rate of tadpoles, body mass, or survival. The effect of long-term predator exposure on tadpole shape depended on body size. Occurrence of predators caused tadpole shape to differ for both small and large tadpoles but not tadpoles of the average body size. Short-term exposure to chemical cues from predators altered the metabolic rate of naïve tadpoles but not tadpoles with prior exposure to predators. Smaller naïve tadpoles reduced their metabolic rate but larger naïve tadpoles enhanced their metabolic rate in response to short-term chemical cues. Chemical cues caused the metabolic rate of naïve tadpoles to be 24% greater than that observed in tadpoles that were reared with predators. Short-term visual cues did not influence the metabolic rate of any tadpoles. Prior exposure to predators did not cause tadpoles to differ in their activity levels or their likelihood to seek a refuge. Exposure to short-term chemical cues increased the number of naïve tadpoles seeking a refuge. Short-term visual cues resulted in more predator exposed tadpoles hiding in a refuge. My results indicate that long-term exposure to predators may compromise the ability of prey to extract resources by causing prey to develop shorter guts. These results further suggest the greater activity of predator exposed tadpoles to be a result of a less efficient digestion system requiring increased foraging effort but the risk of increased activity in the face of predation may be mitigated to some degree by modifications to body shape. This study supports the idea that there are complex interactions among physiology, behavior, and morphology in predator-prey interactions.
Book Synopsis Invasive Species in Forests and Rangelands of the United States by : Therese M. Poland
Download or read book Invasive Species in Forests and Rangelands of the United States written by Therese M. Poland and published by Springer Nature. This book was released on 2021-02-01 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book describes the serious threat of invasive species to native ecosystems. Invasive species have caused and will continue to cause enormous ecological and economic damage with ever increasing world trade. This multi-disciplinary book, written by over 100 national experts, presents the latest research on a wide range of natural science and social science fields that explore the ecology, impacts, and practical tools for management of invasive species. It covers species of all taxonomic groups from insects and pathogens, to plants, vertebrates, and aquatic organisms that impact a diversity of habitats in forests, rangelands and grasslands of the United States. It is well-illustrated, provides summaries of the most important invasive species and issues impacting all regions of the country, and includes a comprehensive primary reference list for each topic. This scientific synthesis provides the cultural, economic, scientific and social context for addressing environmental challenges posed by invasive species and will be a valuable resource for scholars, policy makers, natural resource managers and practitioners.
Download or read book Natural Enemies written by Ann E. Hajek and published by Cambridge University Press. This book was released on 2004-02-12 with total page 396 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher Description
Book Synopsis Co-occurrence and Interactions of Large Invertebrate Predators in Relation to the Bythotrephes Invasion by : Sophie Elizabeth Foster
Download or read book Co-occurrence and Interactions of Large Invertebrate Predators in Relation to the Bythotrephes Invasion written by Sophie Elizabeth Foster and published by . This book was released on 2007 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the Bythotrephes invasion in North American Lakes, a number of cladoceran zooplankton species have declined dramatically and overall cladoceran abundance is reduced. In this study I examined Bythotrephes impacts on the native invertebrate predators, including the cladoceran Leptodora kindtii, the glacial relict crustacean, Mysis relicta, and the dipteran larva, Chaoborus spp. These species rely on zooplankton as prey and therefore may suffer as a result of the Bythotrephes invasion. In this study I also examined the role of invertebrate predators in lake food webs in relation to the Bythotrephes invasion. I measured Bythotrephes and native invertebrate abundances, consumption and estimated trophic levels using stable isotopes delta15N and delta13C in a comparison study between inland lakes with Bythotrephes and with no Bythotrephes. In lakes with Bythotrephes the overall consumption demand by invertebrate predators was 25% greater than in lakes with no Bythotrephes. This increase in demand was due to the energetic demands by Bythotrephes although there were lower abundances of both Leptodora and Chaoborus in lakes with Bythotrephes than in lakes without Bythotrephes. Trophic position of native invertebrate predators did not differ between invaded and non-invaded lakes suggesting native invertebrate predators do not feed extensively on Bythotrephes . Stable isotope delta15N and delta13C analysis suggested that there is a greater degree of similarity between the diets of Mysis and Chaoborus and between the diets of Leptodora and Bythotrephes. In addition, there is a high degree of overlap in the vertical distribution of Leptodora and Bythotrephes. Leptodora were smaller and less abundant in invaded lakes than in non-invaded lakes. One possible explanation is competition for prey between Bythotrephes and Leptodora. Indeed cladocerans were smaller in the epilimnion of invaded compared to non-invaded lakes. Understanding the effects of Bythotrephes on native food webs is an ongoing challenge. In this study I demonstrate that Bythotrephes increases the role of invertebrate predators, alters the availability of prey to native invertebrate predators and causes declines in the abundance of Leptodora.
Book Synopsis Free-ranging Cats by : Stephen Spotte
Download or read book Free-ranging Cats written by Stephen Spotte and published by John Wiley & Sons. This book was released on 2014-07-16 with total page 447 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feral and stray domestic cats occupy many different habitats. They can resist dehydration for months by relying exclusively on the tissue water of their prey allowing them to colonize remote deserts and other inhospitable places. They thrive and reproduce in humid equatorial rainforests and windswept subantarctic islands. In many areas of the world feral cats have driven some species of birds and mammals to extinction and others to the edge, becoming a huge conservation concern. With the control of feral and stray cats now a top conservation priority, biologists are intensifying efforts to understand cat behaviour, reproductive biology, use of space, intraspecies interaction, dietary requirements, prey preferences, and vulnerability to different management strategies. This book provides the most comprehensive review yet published on the behavior, ecology and management of free-ranging domestic cats, whether they be owned, stray, or feral. It reviews management methods and their progress, and questions several widely accepted views of free-ranging cats, notably that they live within dominance hierarchies and are highly social. Insightful and objective, this book includes: a functional approach, emphasizing sensory biology, reproductive physiology, nutrition, and space partitioning; clear treatment of how free-ranging cats should be managed; extensive critical interpretation of the world's existing literature; results of studies of cats in laboratories under controlled conditions, with data that can also be applied to pet cats. Free-ranging Cats: Behavior, Ecology, Management is valuable to ecologists, conservation scientists, animal behaviorists, wildlife nutritionists, wildlife biologists, research and wildlife veterinarians, clinical veterinarians, mammalogists, and park and game reserve planners and administrators.
