Download or read book Caspian Tern Hydroprogne Caspia Foraging Ecology and Predation on Juvenile Salmonids in San Francisco Bay California written by Lindsay J. Adrean and published by . This book was released on 2011 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: Brooks Island, located in central San Francisco Bay, California, currently supports the largest breeding colony of Caspian terns (Hydroprogne caspia) in the Bay Area, and is one of several proposed relocation sites for some Caspian terns from the world's largest colony in the Columbia River estuary of Oregon. Juvenile salmonids have been identified in the diet of Caspian terns nesting at Brooks Island, so I investigated whether the colony, at its current or an enhanced size, poses a threat to the recovery of several runs of salmonids (Oncorhynchus spp.) in San Francisco Bay that are listed under the U.S. Endangered Species Act (ESA). I also examined the foraging ecology of Brooks Island Caspian terns to 1) determine whether the colony is suitable for expansion based on availability of forage fish resources, a factor potentially limiting the size and productivity of the colony, and 2) investigate how Caspian terns nesting at this colony exploit forage fish resources. I used a bioenergetics modeling approach, employing estimates of tern energy requirements and proportions of energy supplied by various prey types, to estimate consumption of juvenile salmonids by Caspian terns nesting on Brooks Island during 2008 and 2009. Estimated salmonid consumption was 205,000 smolts (95% CI: 175,000 - 245,000 smolts) in 2008 and 167,000 smolts (95% CI: 144,000 - 191,000 smolts) in 2009. Predation rates on ESA-listed Central Valley spring-run Chinook salmon (O. tshawytscha; 0.08%) were lower than those on unlisted fall-run Chinook salmon (1.0%). Average per capita predation rates on juvenile salmonids by Brooks Island Caspian terns (2008: 126 fish; 2009: 123 fish) were less than half those of Caspian terns nesting in the Columbia River estuary. If the current downward trend in the number of Caspian terns nesting on Brooks Island continues until the colony is no longer extant, the resulting declines in predation on salmonids would lead to increases in annual population growth rates ([delta lambda]) of salmonid runs of just small fractions of one percentage point. The proposed enhancement of the Brooks Island Caspian tern colony to 3,000 individuals would at most cause declines in annual population growth rates of 0.3% for fall-run Chinook salmon and 0.02% for threatened spring-run Chinook salmon, assuming that smolt mortality from tern predation is 100% additive. This level of impact to the ESA-listed spring-run Chinook salmon stock is less than the level considered acceptable by the National Marine Fisheries Service ([delta lambda] = 0.05%). Radio-tracking of Caspian terns nesting on Brooks Island revealed that the maximum foraging distance from the colony was 80 km. The median foraging distance from the colony was greater in 2009 compared to 2008 (20.6 km vs. 14.0 km), average number of foraging trips per day was higher (4.4 vs. 3.4 foraging trips), and average adult colony attendance was lower (43% vs. 52% of daylight hours). These results indicate that the colony was more food-limited during the 2009 breeding season, concurrent with anomalous downwelling along the coast of northern California and reduced availability and size of marine forage fishes, such as herring, sardines, and anchovies. Caspian terns used a number of core foraging areas within 30 km of the Brooks Island colony, both inside and just outside the Bay. Two large core foraging areas were close to or overlapped with the release site for juvenile salmonids in eastern San Pablo Bay, where> 10 million hatchery-raised smolts were released from net pens during both the 2008 and 2009 tern nesting seasons. This finding supports the hypothesis that most juvenile salmonids consumed by terns nesting at the Brooks Island colony were captured at or near the release site. Individual Caspian terns displayed foraging site fidelity, suggesting that foraging at the release site for hatchery-raised salmonids was a learned behavior by some terns. The Brooks Island colony site is within foraging distance of adequate marine forage fish resources in most years, and Caspian terns nesting there are not dependent on juvenile salmonids as a food resource. Consumption of juvenile salmonids by Brooks Island terns would be largely curtailed by modification of hatchery release practices.
Download or read book Caspian Tern Management to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary written by and published by . This book was released on 2005 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Caspian Tern Management to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary written by Wyoming. Game and Fish Department and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alaska Seabird Information Series ASIS written by and published by . This book was released on 2006 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Compilation of seabird species accounts for all seabirds breeding in Alaska and five important nonbreeders. Conservation status, life history, distribution, population size and trends, conservation concerns, and recommended management actions are included in the accounts"--Leaf i.
Download or read book Marine Birds of the Southeastern United States and Gulf of Mexico Charadrillformes written by Roger B. Clapp and published by . This book was released on 1982 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecological Assessment of Selenium in the Aquatic Environment written by Peter M. Chapman and published by CRC Press. This book was released on 2010-05-06 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Based on the work and contributions of 46 scientists, managers, and policymakers, Ecological Assessment of Selenium in the Aquatic Environment documents the state of the science and explores how to use this information when assessing and managing the environmental effects of Se. A focused discussion on the fate and effects of Se in aquatic ecosyste
Download or read book Birds of the North Gulf Coast Prince William Sound Region Alaska written by M. E. Isleib and published by University of Alaska Press. This book was released on 1973 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Report on status, abundance, habitat, and seasonal occurrence of 219 species of birds as observed on the North Gulf Coast of Alaska-Prince William Sound. An annotated list of birds is provided.
Download or read book Geomorphology of the Lower Copper River Alaska written by Timothy P. Brabets and published by . This book was released on 1997 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Freshwater Biodiversity written by David Dudgeon and published by Cambridge University Press. This book was released on 2020-05-21 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: Growing human populations and higher demands for water impose increasing impacts and stresses upon freshwater biodiversity. Their combined effects have made these animals more endangered than their terrestrial and marine counterparts. Overuse and contamination of water, overexploitation and overfishing, introduction of alien species, and alteration of natural flow regimes have led to a 'great thinning' and declines in abundance of freshwater animals, a 'great shrinking' in body size with reductions in large species, and a 'great mixing' whereby the spread of introduced species has tended to homogenize previously dissimilar communities in different parts of the world. Climate change and warming temperatures will alter global water availability, and exacerbate the other threat factors. What conservation action is needed to halt or reverse these trends, and preserve freshwater biodiversity in a rapidly changing world? This book offers the tools and approaches that can be deployed to help conserve freshwater biodiversity.
Download or read book Indicators of Climate Change in California written by Carmen Milanes (Environmentalist) and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Great Salt Lake Biology written by Bonnie K. Baxter and published by Springer Nature. This book was released on 2020-07-03 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: Great Salt Lake is an enormous terminal lake in the western United States. It is a highly productive ecosystem, which has global significance for millions of migrating birds who rely on this critical feeding station on their journey through the American west. For the human population in the adjacent metropolitan area, this body of water provides a significant economic resource as industries, such as brine shrimp harvesting and mineral extraction, generate jobs and income for the state of Utah. In addition, the lake provides the local population with ecosystem services, especially the creation of mountain snowpack that generates water supply, and the prevention of dust that may impair air quality. As a result of climate change and water diversions for consumptive uses, terminal lakes are shrinking worldwide, and this edited volume is written in this urgent context. This is the first book ever centered on Great Salt Lake biology. Current and novel data presented here paint a comprehensive picture, building on our past understanding and adding complexity. Together, the authors explore this saline lake from the microbial diversity to the invertebrates and the birds who eat them, along a dynamic salinity gradient with unique geochemistry. Some unusual perspectives are included, including the impact of tar seeps on the lake biology and why Great Salt Lake may help us search for life on Mars. Also, we consider the role of human perceptions and our effect on the biology of the lake. The editors made an effort to involve a diversity of experts on the Great Salt Lake system, but also to include unheard voices such as scientists at state agencies or non-profit advocacy organizations. This book is a timely discussion of a terminal lake that is significant, unique, and threatened.
Download or read book Management and Ecology of River Fisheries written by Ian G. Cowx and published by John Wiley & Sons. This book was released on 2008-04-30 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this edited work, international experts in fisheries management and ecology review and appraise the status of river fisheries, assessment methodology, constraints on development, issues and options regarding management and associated problems in both temperate and tropical countries. Recommendations are made to improve management and an attempt is made to provide guidelines for formulating policy, for planning methodology and for evaluating future activities. Assessment of fish community structure and dynamics. Factors constraining stock recruitment. Fish habitat requirements. Instream flow needs. Impact of water resource schemes. Rehabilitation of river fisheries. Enhancement of fish stocks. Exploitation of stocks. Management of migratory fish stocks. Conservation of endangered species. Integrated river management. Bioeconomic issues. Legislation. Multinational management of rivers. Case studies.
Download or read book Explorations in Ethnobiology written by Marsha Quinlan and published by . This book was released on 2012-12-01 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of 12 ethnobiological papers compiled in honor of ethnobiologist Amadeo Rea, plus an essay by Rea himself, reflect the depth and breadth of the field of ethnobiology. Each chapter explores some aspect of the rich and complex relationship of indigenous and other subsistence-based peoples with their biological worlds. The volume's chapters are authored by some of today's leaders in ethnobiology and cover a range of ethnobotanical and ethnozoological topics from the distant past to the immediate present. Using a variety of methods from interviews with knowledge holders to cutting edge quantitative linguistic analyses, the papers cover broadly relevant themes such as conservation and the linkages between biological diversity, cultural diversity, and their resilience. This book is the first volume in the Contributions in Ethnobiology series.
Download or read book Patterns in the Ocean written by Andrew Bakun and published by . This book was released on 1996 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Status Ecology and Conservation of Marine Birds of the North Pacific written by Kees Vermeer and published by . This book was released on 1993 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seabird Bycatch written by Edward F. Melvin and published by Alaska Sea Grant College Program. This book was released on 2001 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seabird Bycatch significantly adds to the knowledge base of seabird mortality in commercial fisheries, and emphasizes the importance of comprehensive solutions. The product of a 1999 symposium held by the Pacific Seabird Group, Seabird Bycatch is a response to escalating bycatch, a global conservation and fisheries management issue.
Download or read book Bird Conservation Implementation and Integration in the Americas written by Asilomar California and published by . This book was released on 2005 with total page 651 pages. Available in PDF, EPUB and Kindle. Book excerpt:
