Download or read book Use of Stable Isotopes to Determine Diets of Living and Extinct Bears written by Grant Vaughan Hilderbrand and published by . This book was released on 1995 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applications of Stable Isotope Analysis to Advancing the Understanding of Brown Bear Dietary Ecology written by Matthew C. Rogers and published by . This book was released on 2021 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dietary ecology is one of the most important drivers of brown bear fitness at the individual and population levels. However, researchers do not have an in-depth understanding of the trophic niche breadth, diet composition, and seasonal diet variation for most Alaskan populations. I set out to better understand multiple facets of brown bear dietary ecology using stable isotope analysis (13C & 15N) as the primary tool to infer brown bear diet and gain insights into their trophic niche, dietary seasonality, dietary generalism and specialism, and isotopic trophic discrimination factors. I determined that using sectioned hair samples is the best practice for determining the isotopic trophic niche of brown bears. Additionally, I determined amino acid trophic discrimination factors for brown bears and explored the ability to separate salmon species in bear diets. I also used stable isotope mixing models with sectioned hair samples to infer seasonal dietary patterns of individual bears in five distinct Alaskan ecosystems. Approximately one-quarter of bears relied solely on vegetation over multiple years despite access to other sources of nutrition; these bears could be considered specialists. Other bears, approximately half, switched diets seasonally but had the same pattern of resource use year over year, a foraging class that I termed persistent seasonal generalism. Approximately one-quarter of bears did not have a persistent dietary pattern across years and could be considered true generalists. Most bears appear to have preferred dietary patterns that are persistent through time, which may be indicative of foraging inertia; maintaining foraging patterns even when faced with changing resource availability due to natural fluctuations, disturbance, or climate change. The sum of this work advances our understanding of brown bear dietary ecology from the individual seasonal level to population level degrees of generalism and specialism, and the methods developed can be applied to many species for which dietary ecology information is difficult to obtain.

Download or read book Selecting the Best Stable Isotope Mixing Model to Estimate Grizzly Bear Diets in the Greater Yellowstone Ecosystem written by John B. Hopkins (III.) and published by . This book was released on 2017 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Past research indicates that whitebark pine seeds are a critical food source for Threatened grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem (GYE). In recent decades, whitebark pine forests have declined markedly due to pine beetle infestation, invasive blister rust, and landscape-level fires. To date, no study has reliably estimated the contribution of whitebark pine seeds to the diets of grizzlies through time. We used stable isotope ratios (expressed as ?13C, ?15N, and ?34S values) measured in grizzly bear hair and their major food sources to estimate the diets of grizzlies sampled in Cooke City Basin, Montana. We found that stable isotope mixing models that included different combinations of stable isotope values for bears and their foods generated similar proportional dietary contributions. Estimates generated by our top model suggest that whitebark pine seeds (35±10%) and other plant foods (56±10%) were more important than meat (9±8%) to grizzly bears sampled in the study area. Stable isotope values measured in bear hair collected elsewhere in the GYE and North America support our conclusions about plant-based foraging. We recommend that researchers consider model selection when estimating the diets of animals using stable isotope mixing models. We also urge researchers to use the new statistical framework described here to estimate the dietary responses of grizzlies to declines in whitebark pine seeds and other important food sources through time in the GYE (e.g., cutthroat trout), as such information could be useful in predicting how the population will adapt to future environmental change.

Download or read book Use of Isotopic Sulfur to Determine Whitebark Pine Consumption by Yellowstone Bears written by Charles C. Schwartz and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Use of naturally occurring stable isotopes to estimate assimilated diet of bears is one of the single greatest breakthroughs in nutritional ecology during the past 20 years. Previous research in the Greater Yellowstone Ecosystem (GYE), USA, established a positive relationship between the stable isotope of sulfur ([delta]34S) and consumption of whitebark pine (Pinus albicaulis) seeds. That work combined a limited sample of hair, blood clots, and serum. Here we use a much larger sample to reassess those findings. We contrasted [delta]34S values in spring hair and serum with abundance of seeds of whitebark pine in samples collected from grizzly (Ursus arctos) and American black bears (U. americanus) in the GYE during 2000?2010. Although we found a positive relationship between [delta]34S values in spring hair and pine seed abundance for grizzly bears, the coefficients of determination were small (R2

Download or read book Stable isotopes and the metabolism of the European cave bear written by D. Erle Nelson and published by . This book was released on 1998 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotopic analyses of fossil bones of the extinct European cave bear indicate that this animal was a hibernator with the same unusual metabolic processes as some modern bear species. Thi finding provides useful biological and archaeological information on an extinct species, and the methods themselves may prove generally useful in studies of the metabolisms of modern bears, other hibernators, and perhaps of starving animals.

Download or read book Stable Isotopes in Human Nutrition written by S. A. Abrams and published by CABI. This book was released on 2003-04-25 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The use of stable isotopes in nutritional studies is now widespread, and the technique is becoming increasingly popular. Practical applications are numerous and include:calcium and iron absorption studiesstudies looking at the impacts of diet, physical activity, aging, and medical therapy and supplementation on nutrient metabolismthe measurement of energy cost of pregnancystudies on the causes of growth faltering in infantsinvestigations into childhood and adult obesity.This book is designed as a laboratory handbook of methods used to perform stable isotope studies in humans. It covers basic principles, dosage information, sample preparation procedures, analytical instrumentation, and necessary mathematical methods and provides the fundamentals to enable researchers to evaluate and establish stable isotope methods in their own laboratories.

Download or read book Use of Sulfur and Nitrogen Stable Isotopes to Determine the Importance of Whitebark Pine Nuts to Yellowstone Grizzly Bears written by Laura Anne Felicetti and published by . This book was released on 2003 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whitebark pine (Pinus albicaulis) is a masting species that produces relatively large, fat- and protein-rich nuts that are consumed by grizzly bears (Ursus arctos horribilis). Trees produce abundant nut crops in some years and poor crops in other years. Grizzly bear survival in the Greater Yellowstone Ecosystem is strongly linked to variation in pine-nut availability. Because whitebark pine trees are infected with blister rust (Cronartium ribicola), an exotic fungus that has killed the species throughout much of its range in the northern Rocky Mountains, we used stable isotopes to quantify the importance of this food resource to Yellowstone grizzly bears while healthy populations of the trees still exist. Whitebark pine nuts have a sulfur-isotope signature (9.2 ± 1.3% (mean ± 1 SD)) that is distinctly different from those of all other grizzly bear foods (ranging from 1.9 ± 1.7% for all other plants to 3.1 ± 2.6% for ungulates). Feeding trials with captive grizzly bears were used to develop relationships between dietary sulfur-, carbon-, and nitrogen-isotope signatures and those of bear plasma. The sulfur and nitrogen relationships were used to estimate the importance of pine nuts to free-ranging grizzly bears from blood and hair samples collected between 1994 and 2001. During years of poor pine-nut availability, 72% of the bears made minimal use of pine nuts. During years of abundant cone availability, 8 ± 10% of the bears made minimal use of pine nuts, while 67 ± 19% derived over 51% of their assimilated sulfur and nitrogen (i.e., protein) from pine nuts. Pine nuts and meat are two critically important food resources for Yellowstone grizzly bears.

Download or read book Tracking Animal Migration with Stable Isotopes written by Keith A. Hobson and published by Academic Press. This book was released on 2018-09-13 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tracking Animal Migration with Stable Isotopes, Second Edition, provides a complete introduction to new and powerful isotopic tools and applications that track animal migration, reviewing where isotope tracers fit in the modern toolbox of tracking methods. The book provides background information on a broad range of migration scenarios in terrestrial and aquatic systems and summarizes the most cutting-edge developments in the field that are revolutionizing the way migrant individuals and populations are assigned to their true origins. It allows undergraduates, graduate students and non-specialist scientists to adopt and apply isotopes to migration research, and also serves as a useful reference for scientists. The new edition thoroughly updates the information available to the reader on current applications of this technique and provides new tools for the isotopic assignment of individuals to origins, including geostatistical multi-isotope approaches and the ways in which researchers can combine isotopes with routine data in a Bayesian framework to provide best estimates of animal origins. Four new chapters include contributions on applications to the movements of terrestrial mammals, with particular emphasis on how aspects of animal physiology can influence stable isotope values. Includes an animal physiology component that is an in-depth overview of the cautions and caveats related to this technique Covers marine and aquatic isoscapes and methods to track marine organisms for researchers trying to apply isotopic tracking to animals in these environments Features state-of-the-art statistical treatments for assignment and combining diverse datasets

Download or read book Dietary Adjustability of Grizzly Bears and American Black Bears in Yellowstone National Park written by Jennifer Kay Fortin and published by . This book was released on 2013 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grizzly bears (Ursus arctos) and American black bears (U. americanus) are sympatric in much of Yellowstone National Park. Three primary bear foods, cutthroat trout (Oncorhynchus clarki), whitebark pine (Pinus albicaulis) nuts, and elk (Cervus elaphus), have declined in recent years. Because park managers and the public are concerned about the impact created by reductions in these foods, we quantified bear diets to determine how bears living near Yellowstone Lake are adjusting. We estimated diets using: 1) stable isotope and mercury analyses of hair samples collected from captured bears and from hair collection sites established along cutthroat trout spawning streams and 2) visits to recent locations occupied by bears wearing Global Positioning System collars to identify signs of feeding behavior and to collect scats for macroscopic identification of residues. Approximately 45 ± 22% ([x bar] ± SD) of the assimilated nitrogen consumed by male grizzly bears, 38 ± 20% by female grizzly bears, and 23 ± 7% by male and female black bears came from animal matter. These assimilated dietary proportions for female grizzly bears were the same as 10 years earlier in the Lake area and 30 years earlier in the Greater Yellowstone Ecosystem. However, the proportion of meat in the assimilated diet of male grizzly bears decreased over both time frames. The estimated biomass of cutthroat trout consumed by grizzly bears and black bears declined 70% and 95%, respectively, in the decade between 1997?2000 and 2007?2009. Grizzly bears killed an elk calf every 4.3 ± 2.7 days and black bears every 8.0 ± 4.0 days during June. Elk accounted for 84% of all ungulates consumed by both bear species. Whitebark pine nuts continue to be a primary food source for both grizzly bears and black bears when abundant, but are replaced by false-truffles (Rhizopogon spp.) in the diets of female grizzly bears and black bears when nut crops are minimal. Thus, both grizzly bears and black bears continue to adjust to changing resources, with larger grizzly bears continuing to occupy a more carnivorous niche than the smaller, more herbivorous black bear.

Download or read book The Use of Stable Isotopes to Determine Trophic Status and Seasonal Variability in the Diet of Acomys Subspinosus written by Fahiema Daniels and published by . This book was released on 2004 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Relationship of Stable Isotopes to Late Woodland and Fort Ancient Agriculture Mobility and Paleopathologies at the Turpin Site written by Ashley E. McCall and published by . This book was released on 2013 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis uses stable isotope analyses to examine the relationships between diet, migration, paleopathologies, and agriculture for Newtown Phase Late Woodland and Fort Ancient Turpin Phase populations from the type-site, Turpin (33Ha19), located in the lower Little Miami River Valley, Hamilton County, Ohio. Investigating the subsistence strategy and health of the people who inhabited the Turpin site is important because this is one of the earliest locations of maize agriculture in eastern North America. Therefore, the Turpin population is crucial for our understanding of the dietary and health implications of maize agriculture in the Ohio Valley. Human behavioral ecology states that as humans increase their economic reliance on maize agriculture, they decrease their mobility, increase social stratification, and increase their susceptibility to disease. Stable isotope values in human bone collagen and tooth enamel are used to determine dietary composition and mobility. Statistical analyses comparing d13C and d15N values among ages, sexes, and paleopathologies demonstrate that maize was a significant part of the diet (d13C values greater than -14.0%) and that women were deficient in protein (low d15N values). Maize was likely consumed on a regular basis by the Fort Ancient population and made up more than 25% of the diet. With few exceptions, there is little variation in the 87Sr/86Sr isotope levels of enamel carbonate, which is indicative of a semi-sedentary community. There is evidence that a few individuals may have migrated into the area. These immigrations may have been the result of captivity or intertribal marriage.

Download or read book Tracing Carbon Sources of Southern Beaufort Sea and Chukchi Sea Polar Bears Using Stable Isotope Analyses written by Malia E. K. Smith and published by . This book was released on 2020 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Southern Beaufort Sea (SBS) polar bear (Ursus maritimus) subpopulation has declined in response to sea ice loss, while the Chukchi Sea (CS) subpopulation appears stable. The substantial population decline in the SBS subpopulation in recent years is concurrent with increases in the proportion of polar bears coming on shore, and the duration they spend there. Both of these changes have been associated with the loss of access to their primary sea ice habitat, which is mainly used as a platform to hunt seals. The first objective of this study was to determine if the SBS and CS polar bear subpopulations could be distinguished based on stable isotope signatures (delta13C and delta15N values) of bone collagen. The second objective was to examine patterns in SBS polar bear trophic level and terrestrial carbon sources over a 65-year time period, as polar bears have increasingly used coastal environments. We analyzed 112 SBS and CS polar bear bones (predominantly mandibles) from 1954–2019 that had been archived at the University of Alaska Museum of the North, as well as bones from subsistence-harvested polar bears. In addition to delta13C and delta15N, samples from the SBS bears were analyzed for compound-specific stable carbon isotopes of amino acids (delta13CAA values). Another 50 bone collagen samples from terrestrial mammals and pinnipeds from northern Alaska were analyzed for delta13CAA values to provide a regional comparative dataset. Our study showed a significant difference in bulk delta13C (p

Download or read book The Use of Stable Isotopes to Measure Interactions Between Dietary Fiber Vitamin D and Calcium written by Kimberly Blake O'Brien and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Winter Feeding Ecology and Biomagnification of Organochlorine Contaminants in Alaska Polar Bears written by Torsten W. Bentzen and published by . This book was released on 2006 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Dietary pathways expose polar bears to a variety of contaminant profiles and concentrations, ranging from bowhead whale (Balaena mysticetus) as one of the least contaminated marine mammals to the more highly contaminated upper trophic level ringed seal (Phoca hispida) which represent the majority of their annual diet. We used stable isotopes [delta]15N and [delta]13C to estimate trophic status of 139 free-ranging polar bears sampled along Alaska's Beaufort Sea coast in spring 2003 and 2004. The [delta]15N values of polar bear packed blood cells ranged from 18.2% to 21.4% with a mean of 19.5% (SD=0.7) in 2003 and 19.9% (SD=0.7) in 2004. Two-element three-source mixing models indicated that lower trophic level prey, such as scavenged bowhead whale carcasses, may have composed 11-26% (95% CI) of the diet in 2003, and -2-14% (95% CI) of the diet in 2004. Organochlorine (OC) concentrations in subcutaneous adipose tissue were determined for 47 of the polar bears sampled in 2003 and compared to trophic position ([delta]15N). Although many OCs appear not to biomagnify in polar bears, we found positive relationships with [delta]15N in both sexes between concentrations of several highly recalcitrant OCs in models incorporating age, lipid content, and [delta]13C. [Delta]15N was important in explaining variation in OC concentrations, indicating structural differences in food webs and biomagnification of OCs among polar bears related to their sex, age, and the apparent use of lower trophic level prey"--Leaf iii.

Download or read book U S Geological Survey Professional Paper written by and published by . This book was released on 1984 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Treatise on Geochemistry written by and published by Newnes. This book was released on 2013-10-19 with total page 14787 pages. Available in PDF, EPUB and Kindle. Book excerpt: This extensively updated new edition of the widely acclaimed Treatise on Geochemistry has increased its coverage beyond the wide range of geochemical subject areas in the first edition, with five new volumes which include: the history of the atmosphere, geochemistry of mineral deposits, archaeology and anthropology, organic geochemistry and analytical geochemistry. In addition, the original Volume 1 on "Meteorites, Comets, and Planets" was expanded into two separate volumes dealing with meteorites and planets, respectively. These additions increased the number of volumes in the Treatise from 9 to 15 with the index/appendices volume remaining as the last volume (Volume 16). Each of the original volumes was scrutinized by the appropriate volume editors, with respect to necessary revisions as well as additions and deletions. As a result, 27% were republished without major changes, 66% were revised and 126 new chapters were added. In a many-faceted field such as Geochemistry, explaining and understanding how one sub-field relates to another is key. Instructors will find the complete overviews with extensive cross-referencing useful additions to their course packs and students will benefit from the contextual organization of the subject matter Six new volumes added and 66% updated from 1st edition. The Editors of this work have taken every measure to include the many suggestions received from readers and ensure comprehensiveness of coverage and added value in this 2nd edition The esteemed Board of Volume Editors and Editors-in-Chief worked cohesively to ensure a uniform and consistent approach to the content, which is an amazing accomplishment for a 15-volume work (16 volumes including index volume)!

Download or read book Feeding Ecology in Apes and Other Primates written by Gottfried Hohmann and published by Cambridge University Press. This book was released on 2006 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an evolutionary perspective on feeding behaviour in human and non-human primates.