Linkages Between Wolf Presence And Aspen Recruitment In The Gallatin Elk Winter Range Of Southwestern Montana Usa

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Linkages Between Wolf Presence and Aspen Recruitment in the Gallatin Elk Winter Range of Southwestern Montana, USA

Author : Joshua Simon Halofsky
Publisher :
ISBN 13 :
Total Pages : 13 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Linkages Between Wolf Presence and Aspen Recruitment in the Gallatin Elk Winter Range of Southwestern Montana, USA by : Joshua Simon Halofsky

Download or read book Linkages Between Wolf Presence and Aspen Recruitment in the Gallatin Elk Winter Range of Southwestern Montana, USA written by Joshua Simon Halofsky and published by . This book was released on 2008 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The decline of aspen (Populus tremuloides) in Yellowstone National Park (YNP) has been attributed to conifer encroachment, climatic influences, ungulate herbivory and more recently, a lack of grey wolves (Canis lupus) via trophic cascades. The current study explores evidence of a trophic cascade on aspen decline. We conducted the study in the Gallatin elk winter range of YNP, an area where aspen have not previously been studied. We approximated aspen origination dates fom an age-diameter relationship to examine potential correlations between wolf presence and absence, elk (Cervus elaphus) herbivory and aspen recruitment. A comparative analysis was also conducted between the aspen data collected in the winter range and aspen data collected within two elk exclosures. Within the elk exclosures, aspen recruitment into mature stems began to decline in the 1920s (during wolf extirpation), completely ceased after the 1950s and has only been observed since the 1990s (post-wolf reintroduction). While a host of interacting biophysical factors may influence aspen recruitment and growth, the correlative results between aspen recruitment and historical elk browsing activities, coincident with the presence and absence of wolves, are consistent with a top-down trophic cascade." --Summary.

Progress in Botany 71

Author : Ulrich Lüttge
Publisher : Springer Science & Business Media
ISBN 13 : 3642021670
Total Pages : 418 pages
Book Rating : 4.6/5 (42 download)

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Book Synopsis Progress in Botany 71 by : Ulrich Lüttge

Download or read book Progress in Botany 71 written by Ulrich Lüttge and published by Springer Science & Business Media. This book was released on 2009-11-25 with total page 418 pages. Available in PDF, EPUB and Kindle. Book excerpt: With one volume each year, this series keeps scientists and advanced students informed of the latest developments and results in all areas of the plant sciences. The present volume includes reviews on genetics, cell biology, physiology, comparative morphology, systematics, ecology, and vegetation science.

Trophic Cascades

Author : John Terborgh
Publisher : Island Press
ISBN 13 : 1597268194
Total Pages : 487 pages
Book Rating : 4.5/5 (972 download)

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Book Synopsis Trophic Cascades by : John Terborgh

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.

Ecology in Action

Author : Fred D. Singer
Publisher : Cambridge University Press
ISBN 13 : 1108934498
Total Pages : 2074 pages
Book Rating : 4.1/5 (89 download)

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Book Synopsis Ecology in Action by : Fred D. Singer

Download or read book Ecology in Action written by Fred D. Singer and published by Cambridge University Press. This book was released on 2024-07-04 with total page 2074 pages. Available in PDF, EPUB and Kindle. Book excerpt: Providing students with a solid understanding of core ecological concepts while explaining how ecologists raise and answer real-world questions, this second edition weaves together classic and cutting-edge case studies to bring the subject to life. It is fully updated throughout, including two chapters devoted to climate change ecology, along with extensive coverage of disease ecology, and has been designed specifically to equip students with the tools to analyze and interpret real data. Each chapter emphasizes the linkage between observations, ideas, questions, hypotheses, predictions, results, and conclusions. Additional summary sections describe the development and evolution of research programs in each of ecology's core areas, providing students with essential context. Integrated discussion questions, along with end-of-chapter questions, encourage active learning. These are supported by online resources including tutorials that teach students to use the R programming language for statistical analyses of data presented in the text.

Where the Wild Things Were

Author : William Stolzenburg
Publisher : Bloomsbury Publishing USA
ISBN 13 : 1608196453
Total Pages : 305 pages
Book Rating : 4.6/5 (81 download)

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Book Synopsis Where the Wild Things Were by : William Stolzenburg

Download or read book Where the Wild Things Were written by William Stolzenburg and published by Bloomsbury Publishing USA. This book was released on 2011-01-15 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: For years, predators like snow leopards and white-tipped sharks have been disappearing from the top of the food chain, largely as a result of human action. Science journalist Will Stolzenburg reveals why and how their absence upsets the delicate balance of the world's environment.

Evidence of a Trophic Cascade Among Wolves, Elk, and Aspen in Yellowstone National Park, USA

Author : Joshua Simon Halofsky
Publisher :
ISBN 13 :
Total Pages : 188 pages
Book Rating : 4.:/5 (145 download)

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Book Synopsis Evidence of a Trophic Cascade Among Wolves, Elk, and Aspen in Yellowstone National Park, USA by : Joshua Simon Halofsky

Download or read book Evidence of a Trophic Cascade Among Wolves, Elk, and Aspen in Yellowstone National Park, USA written by Joshua Simon Halofsky and published by . This book was released on 2007 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: According to general top-down trophic theory, in the presence of carnivores, herbivore behavior and/or densities could change and result in an overall decrease in herbivory on plant communities. In this dissertation, I examined the potential relationship between gray wolf (Canis lupus) presence and absence on elk (Cervus elaphus) herbivory of aspen (Populus tremuloides). Based on aspen tree cores and an age-diameter relationship, I approximated aspen origination dates both within and outside two elk exclosures to study long-term patterns of aspen recruitment in the Gallatin elk winter range of northwestern Yellowstone National Park, USA. From aspen data, I concluded that while a host of interacting biophysical factors may influence aspen recruitment and growth, the observed pattern of aspen decline is most correlated with elk herbivory, coincident with the presence and absence of wolves. Outside of the elk winter range, but still within the northwestern portion of the park, I studied growth patterns of clonal upland aspen thickets since wolf reintroduction. Growth patterns were compared in an area burned in the 1988 fires to an adjacent area that was unburned. From the results, I proposed that in addition to any wolf-mediated changes in elk densities, a recoupling of fire with increased elk predation risk in the presence of wolves may improve upland clonal aspen recruitment. To examine the potential for a trophic cascade from the perspective of elk, I measured vigilance behavior in female elk throughout the park during both winter and summer seasons. After vigilance behavior was recorded, I noted the distance to, and type of, objects that could have impeded observed female elk escape from predators. From my model selection procedure, I concluded elk foraging behavior appeared to vary with physical features in the landscape. This variation in foraging behavior with risk of predation provides a potential mechanism to explain the patchy release of preferred woody browse species within the Park. Therefore, in addition to density-mediated effects, the results are consistent with a behaviorally-mediated top-down trophic cascade between wolves, elk, and aspen.

Pluralism in Ecosystem Governance

Author :
Publisher : Academic Press
ISBN 13 : 0323989020
Total Pages : 354 pages
Book Rating : 4.3/5 (239 download)

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Book Synopsis Pluralism in Ecosystem Governance by :

Download or read book Pluralism in Ecosystem Governance written by and published by Academic Press. This book was released on 2022-06-24 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pluralism in Ecosystem Governance, Volume 66 in the Advances in Ecological Research series, highlights new advances in the field, with this release including chapters on An exploration of the effects of political pluralism on decision making for sustainability: Implications for membership on public sector boards, Transdisciplinary agroecological research on biodiversity and ecosystem services for sustainable and climate resilient farming systems in Malawi, Pluralistic approaches in research advance farming and freshwater sustainability efforts in the Great Lakes Basin, Pluralism to manage the complexity of ecosystem services co-production, Of green spaces and gray areas: An Ethnography of Ecosystem Governance in Peri-Urban Bangaluru, India, and more. Additional chapters include Charting Evidence-based Biodiversity Pathways for Sustainable Development in Canada, Community-scientist collaboration in the creation, management and research for two new National Wildlife Areas in Arctic Canada, Rigid social-ecological governance: how discourse inertia has limited pluralism in Doñana, and a variety of other topics. Provides the authority and expertise of leading contributors from an international board of authors Presents the latest release in the Advances in Ecological Research series Updated release includes the latest information on Pluralism in Economic Governance

Cloud-Based Remote Sensing with Google Earth Engine

Author : Jeffrey A. Cardille
Publisher : Springer Nature
ISBN 13 : 3031265882
Total Pages : 1210 pages
Book Rating : 4.0/5 (312 download)

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Book Synopsis Cloud-Based Remote Sensing with Google Earth Engine by : Jeffrey A. Cardille

Download or read book Cloud-Based Remote Sensing with Google Earth Engine written by Jeffrey A. Cardille and published by Springer Nature. This book was released on 2023-10-04 with total page 1210 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book guides its audience—which can range from novice users to experts— though a 55-chapter tour of Google Earth Engine. A sequenced and diverse set of lab materials, this is the product of more than a year of effort from more than a hundred individuals, collecting new exercises from professors, undergraduates, master’s students, PhD students, postdocs, and independent consultants. Cloud Based Remote Sensing with Google Earth Engine is broadly organized into two halves. The first half, Fundamentals, is a set of 31 labs designed to take the reader from being a complete Earth Engine novice to being a quite advanced user. The second half, Applications, presents a tour of the world of Earth Engine across 24 chapters, showing how it is used in a very wide variety of settings that rely on remote-sensing data This is an open access book.

Ecology in Action

Author : Fred Singer
Publisher : Cambridge University Press
ISBN 13 : 110711537X
Total Pages : 721 pages
Book Rating : 4.1/5 (71 download)

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Book Synopsis Ecology in Action by : Fred Singer

Download or read book Ecology in Action written by Fred Singer and published by Cambridge University Press. This book was released on 2016-03-10 with total page 721 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrates process and content of core areas of ecology using an engaging narrative, fascinating case studies, and stunning images throughout.

Canadian Journal of Forest Research

Author :
Publisher :
ISBN 13 :
Total Pages : 474 pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Canadian Journal of Forest Research by :

Download or read book Canadian Journal of Forest Research written by and published by . This book was released on 2016-04 with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem

Author : Eric J. Larsen (Geographer)
Publisher :
ISBN 13 :
Total Pages : 202 pages
Book Rating : 4.:/5 (53 download)

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Book Synopsis Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem by : Eric J. Larsen (Geographer)

Download or read book Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem written by Eric J. Larsen (Geographer) and published by . This book was released on 2001 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerial photographs and field sampling were used to compare aspen (Populus tremuloides) age structure and stand conditions on elk winter range in the northern Yellowstone ecosystem. The elk winter ranges studied were the northern range in Yellowstone National Park (YNP) and the Gallatin National Forest and the Sunlight/Crandall elk winter range in the Shoshone National Forest. I found significant differences when comparing aspen stands inside and outside of YNP borders. The aspen stands in the Gallatin and Sunlight/Crandall areas had a greater incidence of tall aspen suckers and stems in the 1-4, 5-9, and 10-19 cm DBH classes. Aspen stems within YNP had a significantly higher percentage of stems with high levels of bark damage (>66% of bark surface damaged on the lowest 3 m of stem) than aspen stems in stands in the Gallatin or Sunlight/Crandall. An aspen age structure was developed using 598 increment cores. The aspen age structure in YNP was significantly different than the age structures of the Gallatin and Sunlight/Crandall elk winter ranges. The Gallatin and Sunlight/Crandall areas did not have significant differences in their age structures. The greatest differences between YNP and the National Forest areas was in the younger age classes, measured as aspen stems originating between 1920-1989. Within YNP, I found that the aspen age structure, size class distribution, incidence of tall suckers, and the percentage of browsed suckers of the scree habitat type was significantly different than the xeric and mesic habitat types. Scree forms a "natural exclosure" where ungulate browsing is reduced. Aspen stands have successfully recruited new stems into their overstories in all habitat types from 1880-1989 on the Sunlight/Crandall elk winter range and the Gallatin's portion of the northern range. Within YNP, aspen stands successfully recruited new overstory stems between 1860-1929 in all habitat types. Since 1930, YNP aspen have successfully recruited overstory stems mostly in scree habitat type stands and other areas of reduced browsing pressure. I discussed several potential ecological factors impacting aspen overstory recruitment and conclude that changes in ungulate browsing patterns best explains the spatial and temporal pattern I observed.

Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem

Author : Eric J. Larsen
Publisher :
ISBN 13 :
Total Pages : 202 pages
Book Rating : 4.:/5 (15 download)

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Book Synopsis Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem by : Eric J. Larsen

Download or read book Aspen Age Structure and Stand Conditions on Elk Winter Range in the Northern Yellowstone Ecosystem written by Eric J. Larsen and published by . This book was released on 2001 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aerial photographs and field sampling were used to compare aspen (Populus tremuloides) age structure and stand conditions on elk winter range in the northern Yellowstone ecosystem. The elk winter ranges studied were the northern range in Yellowstone National Park (YNP) and the Gallatin National Forest and the Sunlight/Crandall elk winter range in the Shoshone National Forest. I found significant differences when comparing aspen stands inside and outside of YNP borders. The aspen stands in the Gallatin and Sunlight/Crandall areas had a greater incidence of tall aspen suckers and stems in the 1-4, 5-9, and 10-19 cm DBH classes. Aspen stems within YNP had a significantly higher percentage of stems with high levels of bark damage (>66% of bark surface damaged on the lowest 3 m of stem) than aspen stems in stands in the Gallatin or Sunlight/Crandall. An aspen age structure was developed using 598 increment cores. The aspen age structure in YNP was significantly different than the age structures of the Gallatin and Sunlight/Crandall elk winter ranges. The Gallatin and Sunlight/Crandall areas did not have significant differences in their age structures. The greatest differences between YNP and the National Forest areas was in the younger age classes, measured as aspen stems originating between 1920-1989. Within YNP, I found that the aspen age structure, size class distribution, incidence of tall suckers, and the percentage of browsed suckers of the scree habitat type was significantly different than the xeric and mesic habitat types. Scree forms a "natural exclosure" where ungulate browsing is reduced. Aspen stands have successfully recruited new stems into their overstories in all habitat types from 1880-1989 on the Sunlight/Crandall elk winter range and the Gallatin's portion of the northern range. Within YNP, aspen stands successfully recruited new overstory stems between 1860-1929 in all habitat types. Since 1930, YNP aspen have successfully recruited overstory stems mostly in scree habitat type stands and other areas of reduced browsing pressure. I discussed several potential ecological factors impacting aspen overstory recruitment and conclude that changes in ungulate browsing patterns best explains the spatial and temporal pattern I observed.

Risk Effects in Elk

Author : David Alan Christianson
Publisher :
ISBN 13 :
Total Pages : 9 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Risk Effects in Elk by : David Alan Christianson

Download or read book Risk Effects in Elk written by David Alan Christianson and published by . This book was released on 2008 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Risk effects in ungulates are poorly understood but have recently been implicated as an important driver of elk (Cervus elaphus) population dynamics since wolves were reintroduced into the Greater Yellowstone Ecosystem (GYE) of Montana and Wyoming, USA. From December to May in 2004, 2005, and 2006, we recorded the daily presence of wolves on 3 sites occupied by the Upper Gallatin elk population in the northwest corner of the GYE. We estimated the proportion of grasses, conifers, evergreen shrubs, and woody stems in 980 elk fecal samples collected from those 3 sites and tested whether wolf presence affected elk diets. The winter of 2005 was extremely mild allowing us the opportunity to investigate how elk?wolf interactions might change if winter snowpack continues to decline in western North America due to global warming. Snow accumulation consistently favored browsing, and diets during the mild winter were dominated by grass, very similar to the spring diet. In normal winters, adult males grazed less than adult females except when wolves were near because females decreased grazing in response to wolves. Adult males decreased browsing on conifers by half whereas adult females doubled conifer browsing on days when wolves were near. Overall, the sexes had different diets when wolves were absent but showed strong overlap when wolves were present. Diet shifts due to wolves may be causing trophic cascades that have gone unrecognized and probably carry nutritional consequences for wintering elk.

Wolf Presence and Increased Willow Consumption by Yellowstone Elk: Implications for Trophic Cascades

Author : Scott Creel
Publisher :
ISBN 13 :
Total Pages : 13 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Wolf Presence and Increased Willow Consumption by Yellowstone Elk: Implications for Trophic Cascades by : Scott Creel

Download or read book Wolf Presence and Increased Willow Consumption by Yellowstone Elk: Implications for Trophic Cascades written by Scott Creel and published by . This book was released on 2009 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent increases in the height and growth ring width of willow (Salix spp.) and other woody plants in the Greater Yellowstone Ecosystem (GYE) have been attributed to a behaviorally mediated trophic cascade from wolves (Canis lupus) to elk (Cervus elaphus) to willows. This hypothesis predicts that individual elk consume less willow in response to the presence of wolves, but this prediction has not been directly tested with data from elk. We collected 727 fecal samples from elk in the Gallatin Canyon portion of the GYE over three winters and used microhistological methods to quantify the proportion of willow in each sample. We then tested the effect of wolf presence on willow consumption by elk, controlling for the effects of snow conditions, sex, and habitat type. During the period of study, 8?17 wolves occupied the study area, and wolves were locally present on 49% of 260 sampling days, stratified at two-week intervals across three drainages. Over the three years combined, willow consumption was related to snow conditions, wolf presence, and a wolf 3 sex interaction. As expected, willow consumption increased with deeper and less penetrable snow, and this effect was strong. Contrary to expectation, willow consumption increased in the presence of wolves. As with other aspects of antipredator behavior, wolves had different effects on willow consumption by males and females. Finally, we aggregated the data to estimate winter-long mean willow consumption within each drainage; at this broader scale, willow consumption again increased as predation risk increased. In summary, willow consumption was more strongly affected by snow conditions than by the presence of wolves. Interactions between elk and willow were affected by wolves, but not as predicted by the hypothesis that wolf presence favors willow release through a reduction in the selection of willow by individual elk. If a trophic cascade is operating, our results suggest that a decline in the size of the elk population (to roughly one-half its size immediately prior to wolf recovery) may be more important than changes in the willow consumption of individual elk. Finally, reduced grazing of herbaceous vegetation may be equally important for vegetation dynamics.

Characteristics of Winter Wolf Kill Sites in the Southern Yellowstone Ecosystem in the Presence of Elk Feedgrounds

Author : Susannah P. Woodruff
Publisher :
ISBN 13 :
Total Pages : 32 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Characteristics of Winter Wolf Kill Sites in the Southern Yellowstone Ecosystem in the Presence of Elk Feedgrounds by : Susannah P. Woodruff

Download or read book Characteristics of Winter Wolf Kill Sites in the Southern Yellowstone Ecosystem in the Presence of Elk Feedgrounds written by Susannah P. Woodruff and published by . This book was released on 2018 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the spatial use of wolves and how that might relate to prey species may help predict areas with increased likelihood of wolf-prey interactions, areas where wolves may have a higher impact on prey populations, or areas of wolf-livestock conflict. Following reintroduction into Yellowstone National Park in 1995, wolves (Canis lupus) expanded south and recolonized areas in and around Grand Teton National Park in the southern Yellowstone ecosystem in Wyoming, USA. Elk (Cervus elaphus) in this area are supplementally fed at three feedgrounds artificially increasing elk density. We tracked radio-collared and uncollared wolves annually in winter (December to March) from 2000?2008 to investigate kill sites. Our objective was to investigate potential differences in habitat variables (e.g., canopy cover, elevation) between kill sites (n=295) and available (random; n=2,360) locations and investigate whether factors influencing winter wolf kill sites differed in a natural setting (i.e., native winter range) vs. an artificial setting (i.e., near or on feedgrounds). Wolf kills occurred at sites with lower elevation, canopy cover, and terrain roughness compared to random locations. Wolf kills were also slightly farther from packed surfaces (i.e., roads or groomed snowmobile trails) and elk feedgrounds, although still in areas of higher intensity of use by elk compared to random locations. Kill sites on native winter range were considerably more rough (odds ratio 4.47) than those on feedgrounds. Our results suggest research suggesting wolves hunt where the likelihood of encountering prey is high, though in areas where prey distribution is more sparse (i.e., native winter range), wolves may need to rely on rougher terrain for successful hunts. The relationship between areas of high prey use and increased wolf activity has important implications for both wildlife managers and livestock producers. In the future, managers will continue to face the issue of having high concentrations of ungulates, either wild or domestic, and the obvious attraction this has for wolves.

Risk Effects in Elk (Cervus Elaphus)

Author : David Alan Christianson
Publisher :
ISBN 13 :
Total Pages : 366 pages
Book Rating : 4.:/5 (26 download)

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Book Synopsis Risk Effects in Elk (Cervus Elaphus) by : David Alan Christianson

Download or read book Risk Effects in Elk (Cervus Elaphus) written by David Alan Christianson and published by . This book was released on 2008 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Until recently, predators have been though to regulate prey primarily through direct predation, in ecosystems where top down effects have been shown to be important. However, experiments and recent empirical observations show that the costs of antipredator responses in individuals that successfully avoid predation can exert equal or larger driving forces on population dynamics than the numerical effect of direct predation. Such a mechanism has not been explored in a large terrestrial vertebrate. I explored the antipredator responses of elk (Cervus elaphus) to wolves (Canis lupus) in the Upper Gallatin Canyon of southwest Montana, USA, December through May in the winters of 2003-2006. First I reviewed elk winter diet studies to understand what drives elk foraging behavior. Next I modeled the consequences of diet shifts in grazing and browsing on mass dynamics in wintering female elk. I also developed a new nutritional index, fecal chlorophyll, that I used primarily between winter and spring periods of nutrition as foraging constraints (and costs of antipredator response) would be quite different between these two periods. Specifically, I measured foraging behavior, diet selection, and nutrient balance in wintering elk and monitored daily predation risk as wolves moved naturally, in and out of four creek drainages that formed the primary winter range. Elk showed great sensitivity to fine-scale descriptions of wolf predation risk in nearly every response variable. In particular, adult female elk increased browsing on woody stems, sagebrush, and confers while adult males showed the opposition response and increased grazing on days when wolves were present in the same drainage. This work implies that predator may in fact play a large role in ecosystems including ecosystems where predators were deemed non-influential and bottom up effects important.

Knowing Yellowstone

Author : Jerry Johnson
Publisher : Rowman & Littlefield
ISBN 13 : 1589795229
Total Pages : 185 pages
Book Rating : 4.5/5 (897 download)

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Book Synopsis Knowing Yellowstone by : Jerry Johnson

Download or read book Knowing Yellowstone written by Jerry Johnson and published by Rowman & Littlefield. This book was released on 2010-06-16 with total page 185 pages. Available in PDF, EPUB and Kindle. Book excerpt: Visitors to Yellowstone National Park are drawn to the spectacular scenery, unique thermal features, and the large numbers of wild animals easily observed in their natural habitat. The thoughtful visitor to the park cannot help but be captivated by the unparalleled breadth of scientific knowledge needed to understand the intricate interrelationships that make up the yellowstone landscape. Knowing Yellowstone explores how scientists discover what they know about America's first national park and the surrounding lands. The chapter authors are scientists who represent the best of their fields of study. The science they describe is leading the way to our understanding of complex ecosystems worldwide.