Experimental Harvest of the Steller Sea Lion in Alaskan Waters (Classic Reprint)

Experimental Harvest of the Steller Sea Lion in Alaskan Waters (Classic Reprint) PDF

Author: Fredrik V. Thorsteinson

Publisher: Forgotten Books

Published: 2018-02-08

Total Pages: 22

ISBN-13: 9780267220434

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Excerpt from Experimental Harvest of the Steller Sea Lion in Alaskan Waters Sea lion harvesting should take place during the pupping and breeding season when the animals are most available and least wary. On large rookeries specific areas should be hunted alternately for a greater yield. On a hunt-rest basis animals would not vacate an area quickly and would therefore be available for along period of time. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Decline of the Steller Sea Lion in Alaskan Waters

Decline of the Steller Sea Lion in Alaskan Waters PDF

Author: National Research Council

Publisher: National Academies Press

Published: 2003-05-04

Total Pages: 217

ISBN-13: 0309086329

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For an unknown reason, the Steller sea lion population in Alaska has declined by 80% over the past three decades. In 2001, the National Research Council began a study to assess the many hypotheses proposed to explain the sea lion decline including insufficient food due to fishing or the late 1970s climate/regime shift, a disease epidemic, pollution, illegal shooting, subsistence harvest, and predation by killer whales or sharks. The report's analysis indicates that the population decline cannot be explained only by a decreased availability of food; hence other factors, such as predation and illegal shooting, deserve further study. The report recommends a management strategy that could help determine the impact of fisheries on sea lion survival-establishing open and closed fishing areas around sea lion rookeries. This strategy would allow researchers to study sea lions in relatively controlled, contrasting environments. Experimental area closures will help fill some short-term data gaps, but long-term monitoring will be required to understand why sea lions are at a fraction of their former abundance.

Decline of the Steller Sea Lion in Alaskan Waters

Decline of the Steller Sea Lion in Alaskan Waters PDF

Author: National Research Council

Publisher: National Academies Press

Published: 2003-04-04

Total Pages: 216

ISBN-13: 0309168724

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For an unknown reason, the Steller sea lion population in Alaska has declined by 80% over the past three decades. In 2001, the National Research Council began a study to assess the many hypotheses proposed to explain the sea lion decline including insufficient food due to fishing or the late 1970s climate/regime shift, a disease epidemic, pollution, illegal shooting, subsistence harvest, and predation by killer whales or sharks. The report's analysis indicates that the population decline cannot be explained only by a decreased availability of food; hence other factors, such as predation and illegal shooting, deserve further study. The report recommends a management strategy that could help determine the impact of fisheries on sea lion survival-establishing open and closed fishing areas around sea lion rookeries. This strategy would allow researchers to study sea lions in relatively controlled, contrasting environments. Experimental area closures will help fill some short-term data gaps, but long-term monitoring will be required to understand why sea lions are at a fraction of their former abundance.

Ocean Acidification

Ocean Acidification PDF

Author: National Research Council

Publisher: National Academies Press

Published: 2010-09-14

Total Pages: 200

ISBN-13: 030916155X

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The ocean has absorbed a significant portion of all human-made carbon dioxide emissions. This benefits human society by moderating the rate of climate change, but also causes unprecedented changes to ocean chemistry. Carbon dioxide taken up by the ocean decreases the pH of the water and leads to a suite of chemical changes collectively known as ocean acidification. The long term consequences of ocean acidification are not known, but are expected to result in changes to many ecosystems and the services they provide to society. Ocean Acidification: A National Strategy to Meet the Challenges of a Changing Ocean reviews the current state of knowledge, explores gaps in understanding, and identifies several key findings. Like climate change, ocean acidification is a growing global problem that will intensify with continued CO2 emissions and has the potential to change marine ecosystems and affect benefits to society. The federal government has taken positive initial steps by developing a national ocean acidification program, but more information is needed to fully understand and address the threat that ocean acidification may pose to marine ecosystems and the services they provide. In addition, a global observation network of chemical and biological sensors is needed to monitor changes in ocean conditions attributable to acidification.

Human Impacts on Seals, Sea Lions, and Sea Otters

Human Impacts on Seals, Sea Lions, and Sea Otters PDF

Author: Todd J. Braje

Publisher: Univ of California Press

Published: 2011-03-23

Total Pages: 328

ISBN-13: 0520267265

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“The bones recovered from the middens of the northeastern Pacific shorelines have important stories to tell biologists, marine mammalogists, and those concerned with marine conservation. This volume unearths a wealth of information about the historical ecology of seals, sea lions, and sea otters in the North Pacific that spans thousands of years. It provides fascinating insights into how the world once looked, and how it may one day look again as seals, sea lions, and sea otters reclaim and recolonize their former haunts.”—Andrew Trites, Director, Marine Mammal Research Unit, University of British Columbia “Braje and Rick have assembled a compelling set of case studies on the long-term and complex interactions between people, marine mammals, and environments in the Northeast Pacific. The promise of zooarchaeology as historical science is on full display, as researchers use geochemistry, aDNA, morphometrics, and traditional analytic methods to address questions of utmost importance to the long-term health of coastal ecosystems. If this book doesn't convince conservation biology about the need to take the long view of animal histories and ecosystems into account in developing conservation management plans, I'm not sure what will.”—Virginia L. Butler, Department of Anthropology, Portland State University

Responding to Oil Spills in the U.S. Arctic Marine Environment

Responding to Oil Spills in the U.S. Arctic Marine Environment PDF

Author: National Research Council

Publisher: National Academies Press

Published: 2014-08-01

Total Pages: 343

ISBN-13: 030929889X

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U.S. Arctic waters north of the Bering Strait and west of the Canadian border encompass a vast area that is usually ice covered for much of the year, but is increasingly experiencing longer periods and larger areas of open water due to climate change. Sparsely inhabited with a wide variety of ecosystems found nowhere else, this region is vulnerable to damage from human activities. As oil and gas, shipping, and tourism activities increase, the possibilities of an oil spill also increase. How can we best prepare to respond to such an event in this challenging environment? Responding to Oil Spills in the U.S. Arctic Marine Environment reviews the current state of the science regarding oil spill response and environmental assessment in the Arctic region north of the Bering Strait, with emphasis on the potential impacts in U.S. waters. This report describes the unique ecosystems and environment of the Arctic and makes recommendations to provide an effective response effort in these challenging conditions. According to Responding to Oil Spills in the U.S. Arctic Marine Environment, a full range of proven oil spill response technologies is needed in order to minimize the impacts on people and sensitive ecosystems. This report identifies key oil spill research priorities, critical data and monitoring needs, mitigation strategies, and important operational and logistical issues. The Arctic acts as an integrating, regulating, and mediating component of the physical, atmospheric and cryospheric systems that govern life on Earth. Not only does the Arctic serve as regulator of many of the Earth's large-scale systems and processes, but it is also an area where choices made have substantial impact on life and choices everywhere on planet Earth. This report's recommendations will assist environmentalists, industry, state and local policymakers, and anyone interested in the future of this special region to preserve and protect it from damaging oil spills.

Tropical Pinnipeds

Tropical Pinnipeds PDF

Author: Juan J. Alava

Publisher: CRC Press

Published: 2017-07-12

Total Pages: 285

ISBN-13: 1351647636

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Pinnipeds are a fascinating group of marine mammals that play a crucial role as apex predators and sentinels of the functioning and health of marine ecosystems. They are found in the most extreme environments from the Polar regions to the tropics. Pinnipeds are comprised of about 34 species, and of those at least 25% live permanently in tropical zones. This book reviews and updates current research on the biology, marine ecology, bio-monitoring, and conservation of tropical pinniped populations, including their behavior, anthropogenic stressors, and health. It also looks at challenges to be faced for the conservation of tropical pinnipeds, many of which are threatened species.

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