Download or read book Environmental Factors Influencing Recruitment of Walleye in Iowa s Interior Rivers written by Louise Marie Mauldin and published by . This book was released on 1999 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: A questionnaire was distributed to Iowa Department of Natural Resource biologists in 1998 to determine current distribution of walleye in Iowa's interior rivers, and to obtain their opinions of factors affecting natural recruitment. Responses from the survey indicated that walleye were mainly present in larger rivers of the Mississippi River and Missouri River drainages. Poor quality and lack of spawning and nursery habitat and effects of sedimentation were identified by biologists as important factors influencing low reproductive success. Walleye abundance and distribution seems to be directly related to quality of habitat in Iowa rivers. In 1998, environmental factors influencing success of natural recruitment in the Cedar and Wapsipinicon rivers was evaluated. Walleye eggs and larvae were collected. The study showed that spawning substrate was adequate, but nursery habitat was lacking. Few walleye eggs and larvae were collected. Starvation of larval walleye was presumed, because there was a low abundance of zooplankton, the initial food of first feeding walleye, in early spring and suitable nursery areas did not seem to be present in the study reaches. Backwaters, sloughs, lakes, and large impoundments provide refuge from high river currents, and are capable of supplying an abundant food source, critical to survival of young walleye of these rivers. In general, fragmentation of critical habitat for walleye in Iowa rivers results in limited movement and successful natural reproduction. Management efforts should focus on establishing riparian wetlands to provide refuge and a source of food for young walleye, and large, in-stream pools, to provide seasonal habitat for potential walleye broodstock.
Download or read book Synchronous Recruitment of Walleye in the Great Lakes and the Influence of Climate on Recruitment written by Samantha Lee Fedor and published by . This book was released on 2008 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Current concerns about the repercussions of global climate change have stimulated efforts to understand how changing abiotic conditions influence natural populations. Walleye (Sander vitreus) populations have shown marked annual variability that can not be predicted by the size of the spawning population. Previous research has associated this variability with environmental factors such as spring warming rate, river discharge, and storm frequency and intensity. Frequently, however, the predictability of models developed from these studies falters as new data points are added and previous relationships are weakened. Relationships between recruitment and abiotic variables may disintegrate because of the interaction between local and large-scale variables that may not be detected in short time series but become more apparent when many more years are added. By comparing multiple populations within a region, the effects of large-scale variables and local variables should be possible to distinguish, with years of covariation representing years in which climate (or other large-scale factors) is influencing recruitment. We examined the effects of climate on recruitment of walleye by comparing four populations of walleye in the Great Lakes (west basin, Lake Erie, Saginaw Bay, Lake Huron, Green Bay, Lake Michigan, and Bay of Quinte, Lake Ontario) for synchrony of recruitment. Synchrony in recruitment among populations was determined using Pearson's product moment coefficient, and both single site and multi site models were created to test a set of a priori hypotheses regarding various local and large-scale factors influencing recruitment. Synchrony of recruitment occurred between three sites: west basin, Lake Erie, Green Bay, Lake Michigan, and Bay of Quinte, Lake Ontario during 2000-2004. El Niño-Southen Oscillation and the North Atlantic Oscillation were the best predictors of recruitment during 2000-2004. These results suggest that in addition to local weather conditions, large-scale factors influence walleye recruitment in the Great Lakes, and were the dominant variables influencing recruitment during this time. Understanding whether future changes in climate will cause overall increases or decreases in recruitment may help managers choose between more conservative and more liberal management strategies.
Download or read book Commencement written by Iowa State University and published by . This book was released on 1998 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biology Management and Culture of Walleye and Sauger written by Bruce A. Barton and published by . This book was released on 2011-01-01 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Restoration of Aquatic Ecosystems written by National Research Council and published by National Academies Press. This book was released on 1992-01-01 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aldo Leopold, father of the "land ethic," once said, "The time has come for science to busy itself with the earth itself. The first step is to reconstruct a sample of what we had to begin with." The concept he expressedâ€"restorationâ€"is defined in this comprehensive new volume that examines the prospects for repairing the damage society has done to the nation's aquatic resources: lakes, rivers and streams, and wetlands. Restoration of Aquatic Ecosystems outlines a national strategy for aquatic restoration, with practical recommendations, and features case studies of aquatic restoration activities around the country. The committee examines: Key concepts and techniques used in restoration. Common factors in successful restoration efforts. Threats to the health of the nation's aquatic ecosystems. Approaches to evaluation before, during, and after a restoration project. The emerging specialties of restoration and landscape ecology.
Download or read book Dabbling Duck Recruitment in Relation to Habitat and Predators at Union Slough National Wildlife Refuge Iowa written by Joseph P. Fleskes and published by . This book was released on 1991 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Missouri River Natural Resources Bibliography written by Vincent J. Burke and published by . This book was released on 1997 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Muskellunge Management written by Kevin L. Kapuscinski and published by . This book was released on 2017 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Global Climate Change Impacts in the United States written by U.S. Global Change Research Program and published by Cambridge University Press. This book was released on 2009-08-24 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarizes the science of climate change and impacts on the United States, for the public and policymakers.
Download or read book Habitat Suitability Information written by Thomas E. McMahon and published by . This book was released on 1984 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reservoir Fish Habitat Management written by Leandro Miranda and published by . This book was released on 2017-01-02 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fish Passage Technologies written by and published by Office of Technology Assessment. This book was released on 1995 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Classification of Wetlands and Deepwater Habitats of the United States written by U.S. Fish and Wildlife Service and published by . This book was released on 1979 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rapid Bioassessment Protocols for Use in Wadeable Streams and Rivers written by United States. Environmental Protection Agency. Office of Water and published by . This book was released on 1999 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Inland Fisheries Management in North America written by Christopher C. Kohler and published by . This book was released on 1999 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The book covers fishery assessments, habitat and community manipulations, and common practices for managing stream, river, lake, and anadromous fisheries. Chapters on history; ecosystem management; management processes; communications with the public; introduced, undesirable, and endangered species; and the legal and regulatory frameworks provide the context for modern fisheries management." From fisheries.org.
Download or read book Fish and Fisheries Management in Lakes and Reservoirs written by and published by . This book was released on 1993 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Garrison Diversion Unit written by United States. Department of the Interior and published by . This book was released on 1960 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt:
