Download or read book The Population Genetics of Gray Whales Eschrichtius Robustus in the North Pacific written by Aimée R. Lang and published by . This book was released on 2010 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within the North Pacific, gray whales (Eschrichtius robustus) are recognized as distinct eastern and western populations. Although both populations were severely reduced by whaling, the eastern population is generally considered to have recovered while the western population has remained highly depleted. This study expanded on previous work supporting differentiation between eastern and western populations using mtDNA and utilized a panel of 13 microsatellite loci to provide additional insight into the population structure of gray whales. Comparison of microsatellite allele frequencies indicated that eastern and western populations are genetically distinct. Although highly statistically significant, the level of nuclear differentiation between the two populations was relatively low, and the results of sex-specific analyses and assignment testing suggested that some degree of male-biased dispersal may occur between populations. Within the set of samples collected from animals on the primary western feeding ground, relatedness analyses revealed that, consistent with field observations, the fidelity of females and their offspring to this area have been important in shaping the structure of the population. Furthermore, analysis of the paternity of animals first identified as calves, with known and sampled mothers, in the western population between 1995 and 2007 identified 18 males as putative fathers, providing evidence that many of the animals identified on the Sakhalin feeding ground interbreed with each other, presumably while sharing a common migratory route. However, the success of the paternity assignment was lower than expected given the high proportion of sampled animals in this population, suggesting that some males which are contributing to reproduction may not use the primary western feeding ground on a regular basis. The combination of these results suggests that the population structure of gray whales in the North Pacific is more complex than previously thought, and that some movements between the eastern and western populations may take place. However, the maintenance of genetic differences between the two populations supports their recognition as separate eastern and western populations. Future efforts should focus on elucidating the nature and extent of any dispersal which is occurring in order to better understand factors potentially influencing the recovery of the small western population.
Download or read book Genetic Population Structure of Eastern North Pacific Gray Whales Eschrichtius Robustus on Winter Breeding Grounds in Baja California written by David Scott Goerlitz and published by . This book was released on 2001 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Assessment of Western North Pacific Gray Whales Eschrichtius Robustus written by Amanda L. Bradford and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Gray Whale Eschrichtius Robustus written by Mary Lou Jones and published by Academic Press. This book was released on 2012-12-02 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gray Whale: Eschrichtius robustus provides an introduction to the understanding of Eschrichtius robustus or the gray whale. This book explores the life processes, reproduction, and growth of large cetacean populations. Organized into four parts encompassing 25 chapters, this book begins with an overview of the gray whale evolution, fossils, and subfossil remains, range, and systematics in historical times. This text then presents the historical of gray whale exploitation and the economic importance of these whales to humans. Other chapters consider the gray whale migration, abundance, and seasonal distribution in the wake of the California population's recovery from depletion. This book discusses as well the methods used in shore-based censuses during migration and in aerial surveys of gray whales taken on their winter grounds. The final chapter deals with some innovative approaches to the study of free-ranging cetaceans. This book is a valuable resource for anthropologists, paleontologists, biologists, and naturalists.
Download or read book Assessment of Population Structure in the Eastern North Pacific Gray Whale Eschrichtius Robustus written by Anna Maria D'Intino and published by . This book was released on 2011 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Genetics for Animal Conservation written by Giorgio Bertorelle and published by Cambridge University Press. This book was released on 2009-05-28 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: Illustrates the power and utility of the synergy between population genetics and conservation biology in animal conservation.
Download or read book Latitudinal Distribution Calf Growth and Metabolsim and Reproductive Energetics of Gray Whales Eschrichtius Robustus written by James L. Sumich and published by . This book was released on 1986 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gray whales accomplish an annual migration which spans as much as 50° of latitude in the northeast Pacific Ocean. This migration links their summer high latitude feeding grounds with winter calving and breeding areas. The purpose of this study was to determine how adult females apportion their stored lipid reserves while away from their principal feeding areas to accommodate their own maintenance and locomotory needs while developing a fetus and transferring energy through lactation to support growth and maintenance of their calves. Major components of this study included examinations of migratory swimming speeds and costs of transport, of calf growth and mortality rates, of metabolic and heat loss rates, of summer distribution patterns, and of the magnitudes and utilization rates of maternal lipid reserves. The results of this study support the conclusions of other investigations that calf heat losses are similar to minimum observed metabolic rates, and that maintenance and lactation costs can be accommodated without winter feeding by all but the small adult females. It is suggested that present oceanographic conditions in the North Pacific Ocean support a larger gray whale population and allow very different gray whale feeding and migrating patterns than existed during the last glacial maximum.
Download or read book Identifying and Comparing Important Areas for Marine Sustainable Use and Conservation written by Sofie Van Parijs and published by Frontiers Media SA. This book was released on 2024-05-24 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean is under increasing threat from the expansion of human activities. The combined impacts of these threats as well as the potential impacts of climate change and ocean acidification have placed thousands of species at risk of extinction, and have impaired the structure, function, productivity and resilience of marine ecosystems. Currently, some parts of the world's oceans are significantly impacted, yet are without any form of effective management. Only a small proportion of the oceans are within protected area systems. Globally, measures are being taken to increase protection and sustainable management, but application is uncoordinated and not always effective. In order to support effective policy action by countries and competent international and regional organizations, it is critical to build a sound understanding of the most ecologically and biologically important ocean areas that support healthy marine ecosystems so that the necessary steps to ensure the long-term function and resilience of these systems can be taken.
Download or read book Genetic Population Structure of Gray Whales Eschrichtius Robustus that Summer in Clayoquot Sound British Columbia written by Tammy Elaine Steeves and published by . This book was released on 1998 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sex in Cetaceans written by Bernd Würsig and published by Springer Nature. This book was released on 2023-09-25 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sex in Cetaceans provides an up-to-date review of multi-faceted aspects related to mating and reproduction in toothed and baleen whales. This open access book begins with discussions of sexual selection and anatomical traits related to mating and diversity between the sexes. The functions of non-conceptive copulations are reviewed as are different research techniques applied to explore sex in cetaceans. Authors and editors build knowledge of female and male social, mating, and parental strategies and tactics for several specific toothed dolphin/porpoise/whale species and baleen whale species. It concludes with a discussion of potential conservation efforts and ways to help especially beleaguered species and populations the world over. The volume is intended as a major primer of cetacean sex for undergraduate and graduate students, new and established researchers in the field, and the public wishing to learn more.
Download or read book Characterizing Site Fidelity and Habitat Use of the Eastern North Pacific Gray Whale Eschrichtius Robustus in Clayoquot Sound British Columbia written by Jacqueline Ann Clare and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A small number of eastern north Pacific gray whales (Eschrichtius robustus), known as the Pacific Coastal Feeding Group (PCFG) forage during the summer months in the coastal waters between California and Alaska. Although several studies have analyzed the population structure of the PCFG, maternal learning and predator/prey dynamics have not been studied in detail. In this study I characterize fine scale habitat use and site fidelity of eastern north Pacific gray whales in one foraging site within the PCFG's foraging range. I approach this study by examining site fidelity to Clayoquot Sound in increasing detail at different time scales. Using the variability recorded in 17 field seasons of whale census surveys (1997-2013) as a proxy for fluctuations in prey, I suggest that the combination of physical properties of the study area and the life history characteristics of the primary prey species type enable Clayoquot Sound to persist as a foraging site through time.
Download or read book Genetic Population Structure of Gray Whales eschrichtius Robustus that Summer in Clayoquot Sound British Columbia microform written by Steeves, Tammy Elaine and published by Ann Arbor, Mich. : University Microfilms International. This book was released on 1998 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book E Robustus written by James L. Sumich and published by . This book was released on 2014-08-14 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conservation Genetics of Long lived Mammal Populations written by Uma Ramakrishnan and published by . This book was released on 2002 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Population Status of the Eastern North Pacific Stock of Gray Whales in 2009 written by André E. Punt and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: An age- and sex-structured population dynamics model is fitted using Bayesian methods to data on the catches and abundance estimates for the eastern North Pacific (ENP) stock of gray whales (Eschrictius robustus). The prior distributions used for these analyses incorporate revised estimates of abundance for ENP gray whales and account explicitly for the drop in abundance caused by the 1999-2000 mortality event. A series of analyses are conducted to evaluate the sensitivity of the results to different assumptions. The baseline analysis estimates the ENP gray whale population to be above the maximum net productivity level (MNPL), because the posterior mean for the ratio of 2009 abundance to MNPL, termed the optimal sustainable population ratio, is 1.29 (with a posterior median of 1.37 and a 90% probability interval of 0.68-1.51), indicating the population is estimated to be well above MNPL. The baseline analysis estimates a probability of 0.884 that the population is above its MNPL, which means there is a 0.884 probability that it is at its optimum sustainable population size as defined by the U.S. Marine Mammal Protection Act. These results are consistent across all the model runs. The baseline model also estimates the 2009 ENP gray whale population size (posterior mean of 21,911) to be at 85% of its carrying capacity (posterior mean of 25,808), and this is also consistent across all the model runs.
Download or read book The Journal of Cetacean Research and Management written by and published by . This book was released on 2008 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gray Whales written by Robert Busch and published by Heritage House Publishing Co. This book was released on 1998 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tells the complete natural history of the gray whale that is illustrated with over 80 colour photographs, including a number of underwater shots. Along with the details of the life history of the whale, this book covers man's exploitations of the whale, its comeback from the brink of extinction, and its current and future management issues.
