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 Saving the Gray Whale written by Serge Dedina and published by University of Arizona Press. This book was released on 2000-01-01 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Once hunted by whalers and now the darling of ecotourists, the gray whale has become part of the culture, history, politics, and geography of Mexico's most isolated region. After the harvesting of gray whales was banned by international law in 1946, their populations rebounded; but while they are no longer hunted for their oil, these creatures are now chased up and down the lagoons of southern Baja California by whalewatchers. This book uses the biology and politics associated with gray whales in Mexican waters to present an unusual case study in conservation and politics. It provides an inside look at how gray whale conservation decisions are made in Mexico City and examines how those policies and programs are carried out in the calving grounds of San Ignacio Lagoon and Magdalena Bay, where catering to ecotourists is now an integral part of the local economy. More than a study of conservation politics, Dedina's book puts a human face on wildlife conservation. The author lived for two years with residents of Baja communities to understand their attitudes about wildlife conservation and Mexican politics, and he accompanied many in daily activities to show the extent to which the local economy depends on whalewatching. "It is ironic," observes Dedina, "that residents of some of the most isolated fishing villages in North America are helping to redefine our relationship with wild animals. Americans and Europeans brought the gray whale population to the brink of extinction. The inhabitants of San Ignacio Lagoon and Magdalena Bay are helping us to celebrate the whales' survival." By showing us how these animals have helped shape the lifeways of the people with whom they share the lagoons, Saving the Gray Whale demonstrates that gray whales represent both a destructive past and a future with hope.
Download or read book The Grey Whale Eastern North Pacific Population written by Canada. Department of Fisheries and Oceans and published by . This book was released on 2009 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 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 230 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 Status Review of the Eastern North Pacific Stock of Gray Whales written by and published by . This book was released on 1999 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Migrating Eastern North Pacific Gray Whale Behavior Compared Over Multiple Timescales written by Regina Anne Guazzo and published by . This book was released on 2018 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mysticetes (baleen whales) often make long, annual migrations from high latitude summer feeding areas to low latitude wintering areas. Eastern North Pacific gray whales (Eschrichtius robustus) migrate within a few kilometers from shore for most of their route from summer feeding areas in the Bering, Chukchi, and Beaufort Seas to wintering areas in the lagoons along the south-western coast of the Baja California Peninsula in Mexico. This dissertation combines passive acoustic recordings, infrared camera video, and visual sightings to investigate gray whale behavior and how it changes across different timescales. I use a four-element hydrophone array in central California to present the first published full-season acoustic monitoring and tracking of migrating gray whales. I describe the characteristics of calls produced by migrating gray whales and analyze how these characteristics change due to propagation. I show that gray whale behavior changes on diel and seasonal timescales. Notably, gray whales increase their vocalizations at night but their mean swimming behavior does not change, contrary to previous assumptions used in population size estimates. Over seasonal timescales, vocalizing gray whale swimming behavior aligns with previous observations. I explore how passive acoustic and infrared camera monitoring can help quantify whales by calculating cue rates or call and blow rates for migrating gray whales. Acoustic calling rates indicate that the gray whale population size is greater than estimated using visual sightings alone and that calling rate increases over the southbound migration. Infrared camera blow rates are less affected by whale behavior and are useful for daytime and nighttime monitoring, but are limited by visibility and distance. To understand gray whale behavior over seven migration seasons, I use visual daily counts at two sites and single-hydrophone call detections which indicate that migratory behavior seems to be driven more by intrinsic than the tested environmental factors. I find that the proportion of the population using a coastal route through the Southern California Bight, especially past Los Angeles, increased over these years. Understanding the behavior of migrating gray whales will help improve abundance estimates and determine how these whales may be impacted by nearshore anthropogenic activities and climate change.
Download or read book Washington State Status Report for the Gray Whale written by Scott A. Richardson and published by . This book was released on 1997 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Five year Plan for Research and Monitoring of the Eastern North Pacific Population of Gray Whales written by United States. National Marine Fisheries Service. Gray Whale Monitoring Task Group and published by . This book was released on 1993 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Eye of the Whale written by Dick Russell and published by Simon and Schuster. This book was released on 2001 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Eye of the Whale focuses on one great whale in particularthe coastal-traveling California gray whale. Gray whales make the longest migration of any mammal - from the lagoons of Baja California to the feeding grounds of the Bering Strait between Alaska and Siberia (nearly 6,000 miles). That the gray whale exists today is nothing short of miraculous. Whaling fleets twice massacred the species to near extinction - first during the nineteenth century and again during the early part of the twentieth century."--BOOK JACKET.Title Summary field provided by Blackwell North America, Inc. All Rights Reserved
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 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 Lagoon Time written by Steven L. Swartz and published by Laguna San Ignacio Ecosystem Science Program. This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lagoon Time is an extraordinary first-hand account of the experiences and discoveries made by Dr. Steven Swartz and his colleagues in San Ignacio Lagoon, Baja California Sur, Mexico, that provides visitors a look into the human and natural history of Laguna San Ignacio. It is also a field guide to gray whale behavior and the diverse botanical and avian wildlife in the area. All of the net proceeds will support the Laguna San Ignacio Ecosystem Science Program, a project of The Ocean Foundation.
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 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 Marine Mammals of Eastern North Pacific and Arctic Waters written by Delphine Haley and published by Seattle, Wash. : Pacific Search Press. This book was released on 1986 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
