Download or read book Resource Selection Predation Risk and Population Dynamics of Woodland Caribou written by Nicholas James DeCesare and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Woodland caribou (Rangifer tarandus caribou) have experienced population declines and local extirpations across North America. Human disturbance has caused caribou declines indirectly through changes to apparent competition dynamics within the predator-prey community. Apparent competition occurs as a negative indirect interaction between prey species, mediated by their direct interactions with a shared predator. I first review apparent competition, and show that across many endangered species including woodland caribou, human disturbance often causes an asymmetric tilt to the balance among prey species. Landscape disturbance such as forest harvest and energy development have created early seral-stage forests and linear features across the landscape of west-central Alberta. I studied the effects of landscape disturbance on the predator-prey dynamics of woodland caribou, wolves (Canis lupus) and other ungulate prey species in this region. I examined spatial patterns of resource selection by caribou, wolf predation risk, adult female caribou survival and, ultimately, population trend for 9 woodland caribou populations. Caribou avoided disturbance across all scales of resource selection, though avoidance of forestry cut-blocks was strongest at broad home range scales and avoidance of linear features was strongest at fine scales along caribou movement paths. Linear disturbances also increased predation risk by being selected as travel routes for hunting wolves, but did not increase the predation efficiency in terms of kills per time, as hypothesized. Rather, spatial changes in predation efficiency were largely driven by natural landscape heterogeneity. Avoidance by caribou and increased wolf predation risk in disturbed areas indicate functional habitat loss for caribou, yet these patterns alone do not necessarily imply a demographic impact. Spatial analysis of factors influencing adult female survival indicated that caribou resource selection was broadly correlated with survival, but also that wolf predation risk was an additional mortality risk beyond that perceived by caribou. This failure of caribou to non-ideally avoid predation risk may explain my final analysis showing significant and multi-year declines for all populations in west-central Alberta. Ultimately, if caribou conservation is to succeed, management must reverse the ultimate causes shifting the balance of apparent competition at both broad and fine scales across woodland caribou range.

Download or read book Plasticity in Selection Strategies of Woodland Caribou Rangifer Tarandus Caribou During Winter and Calving written by David D. Gustine and published by . This book was released on 2005 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Landscape Change on Behaviour and Risk Perceptions of Predator and Prey Communities on a Heterogeneous Landscape in Alberta and British Columbia Canada written by Gillian Chow-Fraser and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Habitat selection is assumed to be informed by prior knowledge of the costs and benefits associated with habitat patches on heterogeneous landscapes. Ultimately, species should select habitat that maximizes resources acquired, and minimizes risks to mortality. However, landscape change alters the distribution of resources and, therefore, the energetic trade-offs that drive habitat selection. I investigated how landscape change, through anthropogenic disturbance features, affects behavioural decisions within the predator and prey community, and how those choices affect fitness in the boreal forests and foothills of west-central Alberta and east-central British Columbia. In my first data chapter, I investigated how interspecific interactions within the predator community changed across a gradient of anthropogenic disturbances, focusing on the habitat selection of wolverine (Gulo gulo). I used a novel temporally-explicit approach with camera trap data that modelled weekly co-occurrence of species. I found that anthropogenic features facilitated increased competition between wolverine and coyote, which I suggest is the mechanism that drives broad-scale declines of wolverine on disturbed landscapes. In my second chapter, I tested how woodland caribou evaluated risks and rewards associated with predation risk, disturbance features, and forage habitat during the calving period in two herds on landscapes with differing degrees of disturbance. I compared drivers of resource selection between mothers whose calves survived and mothers whose calves died in either herd. I found that resource selection for mothers on the lesser disturbed landscape was driven by a trade off between predation risk and forage habitat, wherein mothers whose calves eventually died prioritized selection of forage habitat over predation risk. However, all mothers on the more disturbed landscape prioritized their resource selection around disturbance features. Mothers whose calves died appeared to select sites closer to well sites, but more strongly avoided cut blocks and recent wildfire burns. I suggest that disturbance features introduce novel costs and rewards that are not traditionally evaluated on undisturbed landscapes, wherein caribou are required to effectively evaluate risks attributed to unique features with consequences for calf survival. More broadly, my research links the mechanisms that drive changes in habitat selection on changing landscapes with implications for species distributions, population dynamics, and evolutionary changes.

Download or read book Wildlife 2001 Populations written by D.R. McCullough and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1156 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1984, a conference called Wildlife 2000: Modeling habitat relationships of terrestrial vertebrates, was held at Stanford Sierra Camp at Fallen Leaf Lake in the Sierra Nevada Mountains of California. The conference was well-received, and the published volume (Verner, J. , M. L. Morrison, and C. J. Ralph, editors. 1986. Wildlife 2000: modeling habitat relationships of terrestrial vertebrates, University of Wisconsin Press, Madison, Wisconsin, USA) proved to be a landmark publication that received a book award by The Wildlife Society. Wildlife 2001: populations was a followup conference with emphasis on the other major biological field of wildlife conservation and management, populations. It was held on July 29-31, 1991, at the Oakland Airport Hilton Hotel in Oakland, California, in accordance with our intent that this conference have a much stronger international representation than did Wildlife 2000. The goal of the conference was to bring together an international group of specialists to address the state of the art in wildlife population dynamics, and set the agenda for future research and management on the threshold of the 21st century. The mix of specialists included workers in theoretical, as well as practical, aspects of wildlife conservation and management. Three general sessions covered methods, modelling, and conservation of threatened species.

Download or read book Energy Development and Wildlife Conservation in Western North America written by David E. Naugle and published by Island Press. This book was released on 2011-02-09 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book "offers a road map for securing North America's energy future while safeguarding its wildlife heritage. Contributing authors, including researchers, managers, planners, and conservationists, show how science can help craft solutions to conflicts between wildlife and energy development by delineating core areas, identifying landscapes that support viable populations, and forecasting future development scenarios and conservation design."--Publisher.

Download or read book Influence of Spatial Variation in Forage Availability and Predation Risk on Habitat Selection by Woodland Caribou Rangifer Tarandus Caribou in Ontario written by Madeleine McGreer and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seasonal Habitat Selection by Resident and Translocated Caribou in Relation to Cougar Predation Risk written by Heather Leech and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mountain caribou, an arboreal lichen-feeding ecotype of woodland caribou (Rangifer tarandus caribou), have been extirpated from much of their historic range. Mountain caribou are federally listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and red-listed by the BC government. Habitat loss and fragmentation of old growth forest is the ultimate cause for population declines. Yet, predation, linked to apparent competition, is the proximate cause for high rates of mortality. One of the most imperiled populations resides in the Purcell Mountains of BC, which was experimentally augmented in 2012 with 19 northern caribou from northern BC. The caribou-predator literature predominantly focuses on the relationship between caribou and wolves (Canis lupus) in northern caribou populations. However, cougars (Puma concolor) have been identified as a major predator of Purcells-South (PS) caribou, yet caribou-cougar interactions remain largely unstudied. I evaluated cougar predation risk in space and time on resident and translocated caribou in the Purcell Mountains.

Download or read book Calf Survival of Woodland Caribou in a Multi predator Ecosystem written by David D. Gustine and published by . This book was released on 2006 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The proximate role of predation in limiting caribou (Rangifer tarandus) populations is well documented, but the long-term effects of predation pressure on selection of calving areas and the subsequent impacts to calving success remain unclear. We examined the relationships among calf survival, predation risk, and vegetation characteristics among 3 calving areas and across spatial scales in the Besa-Prophet River drainage of northern British Columbia"--page 1.

Download or read book Calving Behavior of Boreal Caribou in a Multi predator Multi use Landscape written by Craig Allen DeMars and published by . This book was released on 2015 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: The boreal ecotype of woodland caribou (Rangifer tarandus caribou) is federally listed as Threatened due to population declines throughout its distribution. High mortality rates of neonate calves (≤ 4 weeks old) due to predation are a key demographic factor contributing to population declines and increasing predation has been linked to landscape disturbance within and adjacent to caribou range. To inform management strategies for improving rates of calf survival, I investigated the space use and habitat requirements of female boreal caribou during calving. Space is integral to the calving behaviour of boreal caribou with parturient females dispersing widely on the landscape, a behaviour hypothesized to reduce predation risk. I assessed potential evolutionary drivers of dispersion using simulation analyses that tracked caribou-wolf encounters during the calving season. I specifically assessed whether dispersion decreased predation risk by: (i) increasing predator search time, (ii) reducing predator encounters because individuals are inconspicuous relative to groups, or (iii) eliminating the risk of multiple kills per predator encounter of caribou groups. Simulation outputs show that dispersion only becomes favourable when differential detectability based on group size is combined with the risk of multiple kills per encounter. This latter effect, however, is likely the primary mechanism driving parturient females to disperse because group detectability effects are presumably constant year round. Simulation outputs further demonstrate that if females become increasingly clumped - a pattern that may result if caribou avoid disturbance in highly impacted landscapes - then calf survival is negatively affected. To specifically identify key attributes of calving habitat, I used a three-step process. First, I identified GPS locations where females were accompanied by neonate calves by developing two novel methods for predicting parturition events and neonate survival status based on female movement patterns. These methods predicted parturition with near certainty and provided reasonable estimates of neonate survival, which I further augmented with aerial survey data. Using the partitioned GPS location data, I then developed resource selection functions using a generalized mixed effects modelling approach that explicitly maintained the individual as the sampling and comparative unit. I discriminated calving areas from other areas within caribou range by conducting multiple comparisons based on season and maternal status. These comparisons show that parturient females shifted from bog-dominated winter ranges to calving areas dominated by fens. In general, reducing predation risk was a dominant factor driving calving habitat selection although the shift to fen landscapes indicates that females may be trading off increased predation risk to access higher quality forage because fens are riskier than bogs. As a third step, I explicitly evaluated calving habitat quality by relating maternal selection and use of resources to the probability of neonate survival. These analyses included spatially explicit covariates of predator-specific risk. Surprisingly, variation in landscape disturbance had minimal effect on calf survival; rather, survival was best explained by predation risk from black bears (Ursus americanus). Collectively, my findings yield important insights into the habitat requirements of boreal caribou during calving and highlight that management actions aimed at improving calving habitat quality will need to be conducted at large spatial scales.

Download or read book Foraging Ecology of Woodland Caribou in Boreal and Montane Ecosystems of Northeastern British Columbia written by Kristin Denryter and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Woodland caribou (Rangifer tarandus caribou) are an iconic species of boreal and montane ecosystems, but many populations are declining due to habitat alteration and associated changes in predator-prey dynamics. Summer forage, however, influences lactation, juvenile growth, pregnancy, and survival, thereby affecting individuals and populations. I used tame caribou (of three nutritional classes - lactating, non-lactating, yearling) as a habitat assessment tool, at 135 sites across northeastern British Columbia, to determine: food habits and selection; dry matter intake rates; diet quality; and daily nutrient intakes. My goal was to assess the suitability of nutritional resources in boreal and montane plant communities to support energy and protein requirements of caribou during summer. Caribou were highly selective foragers. Deciduous shrubs were the primary summer forage of caribou; forbs, lichens, and mushrooms were secondary dietary items. Intake rates by caribou increased with increasing bite masses and quantities of accepted forage biomass (vegetation species used proportionately more than or equal to availability). Caribou achieved highest intakes at sites with an abundance of selected deciduous shrubs (e.g., willow-alpine sites, young forests) that afforded large bite masses, whereas lowest intakes occurred where mean bite masses were small (e.g., dry alpine, nutrient-poor forests). Dietary digestible energy (DE) and protein (DP) content, intake rates, and foraging time varied across plant communities and among nutritional classes. Caribou increased foraging time, but could not compensate for low intake rates and some plant communities failed to provide caribou with adequate nutrient intakes to support nutritional demands for lactation and maintenance of body mass. Although highest nutrient intakes were associated with productive sites, predation risk and disturbance may constrain the nutritional benefits caribou can acquire from these sites. In a pilot study, I mapped foodscapes of DE and DP intakes for a herd of free-ranging boreal caribou. Caribou did not select for nutrient intakes, but other factors including food quantity, predation risk, and accuracy of spatial data layers, may have confounded my ability to isolate the role of nutrition in habitat selection. Insights from this study into the nutritional ecology of caribou during summer can better inform caribou conservation and management.

Download or read book Research Techniques in Animal Ecology written by Luigi Boitani and published by Columbia University Press. This book was released on 2000-06-01 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present biodiversity crisis is rife with opportunities to make important conservation decisions; however, the misuse or misapplication of the methods and techniques of animal ecology can have serious consequences for the survival of species. Still, there have been relatively few critical reviews of methodology in the field. This book provides an analysis of some of the most frequently used research techniques in animal ecology, identifying their limitations and misuses, as well as possible solutions to avoid such pitfalls. In the process, contributors to this volume present new perspectives on the collection, analysis, and interpretation of data. Research Techniques in Animal Ecology is an overarching account of central theoretical and methodological controversies in the field, rather than a handbook on the minutiae of techniques. The editors have forged comprehensive presentations of key topics in animal ecology, such as territory and home range estimates, habitation evaluation, population viability analysis, GIS mapping, and measuring the dynamics of societies. Striking a careful balance, each chapter begins by assessing the shortcomings and misapplications of the techniques in question, followed by a thorough review of the current literature, and concluding with possible solutions and suggested guidelines for more robust investigations.

Download or read book Resource Selection by Animals written by B.F. Manly and published by Springer Science & Business Media. This book was released on 2007-05-08 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have written this book as a guide to the design and analysis of field studies of resource selection, concentrating primarily on statistical aspects of the comparison of the use and availability of resources of different types. Our intended audience is field ecologists in general and, in particular, wildlife and fisheries biologists who are attempting to measure the extent to which real animal populations are selective in their choice of food and habitat. As such, we have made no attempt to address those aspects of theoretical ecology that are concerned with how animals might choose their resources if they acted in an optimal manner. The book is based on the concept of a resource selection function (RSF), where this is a function of characteristics measured on resourceunits such that its value for a unit is proportional to the probability of that unit being used. We argue that this concept leads to a unified theory for the analysis and interpretation of data on resource selection and can replace many ad hoc statistical methods that have been used in the past.

Download or read book Trophic Cascades written by John Terborgh and published by Island Press. This book was released on 2013-06-25 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: Trophic cascades—the top-down regulation of ecosystems by predators—are an essential aspect of ecosystem function and well-being. Trophic cascades are often drastically disrupted by human interventions—for example, when wolves and cougars are removed, allowing deer and beaver to become destructive—yet have only recently begun to be considered in the development of conservation and management strategies. Trophic Cascades is the first comprehensive presentation of the science on this subject. It brings together some of the world’s leading scientists and researchers to explain the importance of large animals in regulating ecosystems, and to relate that scientific knowledge to practical conservation. Chapters examine trophic cascades across the world’s major biomes, including intertidal habitats, coastal oceans, lakes, nearshore ecosystems, open oceans, tropical forests, boreal and temperate ecosystems, low arctic scrubland, savannas, and islands. Additional chapters consider aboveground/belowground linkages, predation and ecosystem processes, consumer control by megafauna and fire, and alternative states in ecosystems. An introductory chapter offers a concise overview of trophic cascades, while concluding chapters consider theoretical perspectives and comparative issues. Trophic Cascades provides a scientific basis and justification for the idea that large predators and top-down forcing must be considered in conservation strategies, alongside factors such as habitat preservation and invasive species. It is a groundbreaking work for scientists and managers involved with biodiversity conservation and protection.

Download or read book Resource Selection and Abundance Estimation of Moose written by Wibke Peters and published by . This book was released on 2010 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Woodland caribou (Rangifer tarandus caribou) are threatened across Canada due to human disturbance altering predator-prey dynamics. The niche specialization of caribou enables them to survive in nutrient-poor habitats spatially separated from other ungulates and their shared predators. The conversion of old-growth forests to young seral stands is hypothesized to increase the abundance of moose (Alces alces), the dominant prey for wolves (Canis lupus), resulting in apparent competition. We first examined habitat selection of moose in 2 regions with differing intensities of human disturbance in west-central Alberta and east-central British Columbia to assess how human disturbance affects the spatial separation of moose and caribou. We built resource selection functions with data from global positioning system (GPS) collars deployed on 17 moose (8 in a region with high and 9 in a region with low human disturbance) at 2 spatial scales. Our results indicated that moose in our study area make forage-risk tradeoffs in a hierarchical fashion similar to caribou, potentially eroding spatial separation in human disturbed landscapes. We also evaluated the spatial partitioning of resources by comparing resource use with GPS locations from 17 moose and 17 paired caribou using logistic regression. As expected, human disturbance decreased the resource partitioning between moose and caribou. Thus, systematic moose management and monitoring will be essential for caribou conservation. Currently, a Stratified Random Block (SRB) survey design is widely used to estimate moose populations, but these surveys are expensive and often result in imprecise population estimates when not corrected for sightability bias. We evaluated the application of distance sampling as an alternative to SRB surveys, especially for use in caribou ranges. To correct for moose missed on the transect line, where a detection rate of 100% is critical, we developed a sightability model using 21 radio-collared moose. After correcting for sightability, distance sampling was more precise and efficient than SRB surveys. In this way, more efficient distance sampling methodology can be an important tool for caribou conservation. Combined, our results showed the importance of moose management in caribou ranges due to decreased spatial separation between both ungulate species in disturbed landscapes.

Download or read book Standards for the Development of Habitat Suitability Index Models written by U.S. Fish and Wildlife Service. Division of Ecological Services and published by . This book was released on 1981 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radio Tracking and Animal Populations written by Joshua Millspaugh and published by Academic Press. This book was released on 2001-08-14 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio Tracking and Animal Populations is a succinct synthesis of emerging technologies and their applications to the empirical and theoretical problems of population assessment. The book is divided into sections designed to encompass the various aspects of animal ecology that may be evaluated using radiotelemetry technology - experimental design, equipment and technology, animal movement, resource selection, and demographics. Wildlife biologists at the leading edge of new developments in the technology and its application have joined forces.

Download or read book Foraging written by David W. Stephens and published by University of Chicago Press. This book was released on 2008-09-15 with total page 626 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foraging is fundamental to animal survival and reproduction, yet it is much more than a simple matter of finding food; it is a biological imperative. Animals must find and consume resources to succeed, and they make extraordinary efforts to do so. For instance, pythons rarely eat, but when they do, their meals are large—as much as 60 percent larger than their own bodies. The snake’s digestive system is normally dormant, but during digestion metabolic rates can increase fortyfold. A python digesting quietly on the forest floor has the metabolic rate of thoroughbred in a dead heat. This and related foraging processes have broad applications in ecology, cognitive science, anthropology, and conservation biology—and they can be further extrapolated in economics, neurobiology, and computer science. Foraging is the first comprehensive review of the topic in more than twenty years. A monumental undertaking, this volume brings together twenty-two experts from throughout the field to offer the latest on the mechanics of foraging, modern foraging theory, and foraging ecology. The fourteen essays cover all the relevant issues, including cognition, individual behavior, caching behavior, parental behavior, antipredator behavior, social behavior, population and community ecology, herbivory, and conservation. Considering a wide range of taxa, from birds to mammals to amphibians, Foraging will be the definitive guide to the field.