Download or read book Variations in Gray Whale Feeding Behavior in the Presence of Whale watching Vessels in Clayoquot Sound 1993 1995 written by Joanna Bass and published by . This book was released on 2000 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Variations in Gray Whale Feeding Behaviour in the Presence of Whale watching Vessels in Clayoquot Sound 1993 1995 written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Exploratory Investigation of Gray Whale Eschrichtius Robustus Spatial Foraging Strategy and the Effect of Vessel Traffic written by Steven Garner and published by . This book was released on 1994 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 13th Biennial Conference on the Biology of Marine Mammals written by and published by . This book was released on 1999 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feeding Behavior of Gray Whales in Relation to Patch Dynamics of Their Benthic Prey written by Jo A. Guerrero and published by . This book was released on 1989 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gray Whale Monitoring Study written by and published by . This book was released on 1989 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2001 with total page 820 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gray Whales Eschrichtius Robustus and Mysids family Mysidae written by Stephanie Secord Olsen and published by . This book was released on 2006 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, I present a new approach to prey quantification in the context of the predator-prey relationship between an apex marine predator, the gray whale, (Eschrichtius robustus) and one of its primary prey, mysids (Family Mysidae) in a tertiary foraging area, in Clayoquot Sound, on the west coast of Vancouver, Island, British Columbia. With the use of a remote acoustical sounder, I first quantify mysid patches in the presence of foraging gray whales. Second, I address the biomass in those patches using a new approach to quantification. By creating an estimate of total biomass of mysids in the study area concurrently with the presence of gray whales, I demonstrate the effect that the foraging whales have on their prey. Tracking the changes of the number of whales and the number of patches, including the overall biomass of the patches provides evidence for this relationship. As the number of gray whales in the study area increases steadily from May to July, 2004, the number of mysid patches and biomass decrease during the same period. The number of foraging whales located in the study area ranged from only five in May to thirty-one on July 18th, in a region covering only 25 km of the southwest coast of Flores Island. After this period of foraging, the whales deserted the study area completely, and only one whale was seen during the month of August. The mysid population regroups slightly after the pressure of foraging whales is released, the number of patches and biomass increase a small amount, exhibiting the expected behavioral response of the prey to re-aggregate into tight swarms. The acoustic method for prey quantification is described in detail as this is a first application of this technology to the mysid-gray whale relationship. In this approach, l demonstrate that the Distorted Wave Borne Approximation model (DWBA) is useful to estimate mysid populations. This study provides a key piece in the progression of eight years of ongoing research on the foraging ecology of gray whales in Clayoquot Sound, British Columbia.
Download or read book Gray Whales Eschrichtius Robustus and Mysids family Mysidae written by Stephanie Secord Olsen and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, I present a new approach to prey quantification in the context of the predator-prey relationship between an apex marine predator, the gray whale, (Eschrichtius robustus) and one of its primary prey, mysids (Family Mysidae) in a tertiary foraging area, in Clayoquot Sound, on the west coast of Vancouver, Island, British Columbia. With the use of a remote acoustical sounder, I first quantify mysid patches in the presence of foraging gray whales. Second, I address the biomass in those patches using a new approach to quantification. By creating an estimate of total biomass of mysids in the study area concurrently with the presence of gray whales, I demonstrate the effect that the foraging whales have on their prey. Tracking the changes of the number of whales and the number of patches, including the overall biomass of the patches provides evidence for this relationship. As the number of gray whales in the study area increases steadily from May to July, 2004, the number of mysid patches and biomass decrease during the same period. The number of foraging whales located in the study area ranged from only five in May to thirty-one on July 18th, in a region covering only 25 km of the southwest coast of Flores Island. After this period of foraging, the whales deserted the study area completely, and only one whale was seen during the month of August. The mysid population regroups slightly after the pressure of foraging whales is released, the number of patches and biomass increase a small amount, exhibiting the expected behavioral response of the prey to re-aggregate into tight swarms. The acoustic method for prey quantification is described in detail as this is a first application of this technology to the mysid-gray whale relationship. In this approach, l demonstrate that the Distorted Wave Borne Approximation model (DWBA) is useful to estimate mysid populations. This study provides a key piece in the progression of eight years of ongoing research on the foraging ecology of gray whales in Clayoquot Sound, British Columbia.
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.
Download or read book Gray Whales Eschrichtius Robustus and Mysids family Mysidae the Predator prey Relationship and a New Approach to Prey Quantification in Clayoquot Sound British Columbia written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, I present a new approach to prey quantification in the context of the predator-prey relationship between an apex marine predator, the gray whale, (Eschrichtius robustus) and one of its primary prey, mysids (Family Mysidae) in a tertiary foraging area, in Clayoquot Sound, on the west coast of Vancouver, Island, British Columbia. With the use of a remote acoustical sounder, I first quantify mysid patches in the presence of foraging gray whales. Second, I address the biomass in those patches using a new approach to quantification. By creating an estimate of total biomass of mysids in the study area concurrently with the presence of gray whales, I demonstrate the effect that the foraging whales have on their prey. Tracking the changes of the number of whales and the number of patches, including the overall biomass of the patches provides evidence for this relationship. As the number of gray whales in the study area increases steadily from May to July, 2004, the number of mysid patches and biomass decrease during the same period. The number of foraging whales located in the study area ranged from only five in May to thirty-one on July 18th, in a region covering only 25 km of the southwest coast of Flores Island. After this period of foraging, the whales deserted the study area completely, and only one whale was seen during the month of August. The mysid population regroups slightly after the pressure of foraging whales is released, the number of patches and biomass increase a small amount, exhibiting the expected behavioral response of the prey to re-aggregate into tight swarms. The acoustic method for prey quantification is described in detail as this is a first application of this technology to the mysid-gray whale relationship. In this approach, l demonstrate that the Distorted Wave Borne Approximation model (DWBA) is useful to estimate mysid populations. This study provides a key piece in the progression of eight years of ongoing research on the foragi.
Download or read book Report of the Workshop on the Scientific Aspects of Managing Whale Watching written by and published by . This book was released on 1996 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Foraging Ecology of Gray Whales in Clayoquot Sound Interactions Between Predator and Prey Across a Continuum of Scales written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the ecology of an organism is fundamental for defining conservation and management priorities for wildlife and natural ecosystems. The most basic ecological framework identifies the key components of an organism's habitat, and the scale for measuring the quality of those features. How these core needs are expressed and vary in the surrounding ecosystem changes over time and space. In marine systems, the physical environment has few strict boundaries, and variations regularly occur on a scale from days to decades. The dynamic and patchy nature of marine habitat makes defining the ecological roles of an animal difficult, even where baseline data exists. In this study I analyze long term field records on the ecological interactions between foraging gray whales (Eschrichtius robustus), and their mysid prey (Family mysidae) in Clayoquot Sound, B.C. By looking at spatial and temporal shifts at both trophic levels, I measure foraging responses and requirements, and assess prey resource availability and resiliency in the marine environment at a series of scales. Appreciation for bottom-up and topdown trophic interactions provides the foundation for identifying natural variability in marine habitat, and a baseline for conservation measures that seek to use marine predators as a barometer of broader ecosystem health.
Download or read book Anthropogenic Disturbance of Western Gray Whale Behavior Off Sakhalin Island Russia written by Glenn Andrew Gailey and published by . This book was released on 2013 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: The western North Pacific population of gray whales (Eschrichtius robustus) is critically endangered of extinction. The population size is estimated to be 131 individuals with 31 reproductive females. Throughout their potential home range, the western gray whale population face several threats to their future survival. On their only known feeding grounds off the northeastern coast of Sakhalin Island, Russia, anthropogenic activity has increased in the past decade due to oil and gas exploration and platform/pipeline construction. This dissertation examines the influences of geophysical seismic surveys (pulse sounds) and platform/pipeline installation (continuous sounds). Each chapter progressively improves upon behavioral models that assess changes in gray whale movements and respirations relative to anthropogenic activity. Theodolite tracking and focal follow methodologies were employed to collect gray whales' movement and respiration information during and in the absence of anthropogenic activity. Spatial, temporal, environmental, and acoustic (pulse and/or continuous) sound levels and non-sound related anthropogenic variables were included as explanatory variables to examine their influence on movement and respiration response variables, such as speed, orientations, dive/surface time, breathing rates, etc. During the 3-D seismic activity, gray whales traveled faster, changed directions of movement less, were recorded farther from shore and stayed underwater longer between respirations as the received sound level exposure increased. During platform/pipeline installations, western gray whales increased their distance from shore with indicators of stress (rapid breathing) and observed to be sensitive to close distance of approach by vessels. No acoustic influence on western gray whale behavior was found during a 4-D seismic survey; however, sample sizes were small in this study to sufficiently detect more subtle to moderate changes in gray whale behavior. These studies illustrate short-term influences anthropogenic activity had on western gray whale behavior which could lead to longer-term responses that may be detrimental to the survival of certain individuals and/or the population. A comprehensive analyses are proposed to increase sample sizes to identify subtle to moderate behavioral changes as well as examine alternative hypotheses to the null hypothesis of no impact used in this dissertation. With the potential to displace individuals/population out of critical feeding habitats needed for their annual survival and the expected increase of anthropogenic activity in the future, this dissertation highlights the importance to monitor and identify problems and suggest alternatives to development/activities that may be impacting this endangered population of gray whales. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149559
Download or read book The Journal of Cetacean Research and Management written by and published by . This book was released on 2000 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biology of Marine Mammals written by John E. Reynolds and published by Smithsonian Institution. This book was released on 1999-09-17 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: Taking an integrated approach to the biology of marine carnivores, cetaceans, and sirenians, twenty-two prominent researchers compare marine mammals with one another and with terrestrial mammals, providing a framework for fundamental biological and ecological concepts. They describe functional morphology, sensory systems, energetics, reproduction, communication and cognition, behavior, distribution, population biology, and feeding ecology. They also detail the physiological adaptations—for such activities and processes as diving, thermo-regulation, osmoregulation, and orientation—that enable marine mammals to exploit their aquatic environment.
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.
