Author: Kenneth H. MosherPublisher:
ISBN:
Category : Pacific salmon
Languages : en
Pages : 28
Book Description
Identification of Pacific Salmon and Steelhead Trout by Scale Characteristics
Author: Kenneth H. MosherPublisher:
ISBN:
Category : Pacific salmon
Languages : en
Pages : 28
Book Description
Identification of Pacific Salmon and Steelhead Trout by Scale Characteristics (Classic Reprint)
Author: Kenneth H. MosherPublisher: Forgotten Books
ISBN: 9781334746970
Category : Science
Languages : en
Pages : 26
Book Description
Excerpt from Identification of Pacific Salmon and Steelhead Trout by Scale Characteristics In the following sections various subjects bearing on the use of scales for identification of species will be discussed. 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.
Identification of Pacific Salmon and Steelhead Trout ByScaleCharecteristics
Author: K. H. MosherCircular
Author: Sport Fishery Abstracts
Author: Racial Identification of Chinook Salmon (Oncorhynchus Tshawytscha) and Juvenile Steelhead Trout (Salmo Gairdneri)
Author: James T. MartinPublisher:
ISBN:
Category : Salmon
Languages : en
Pages : 64
Book Description
Efforts to manage stocks of salmonids in Pacific Northwest stream systems are complicated by the occurrence of several runs of a species thought to represent races rearing sympatrically as juveniles. In order to collect the population statistics needed to properly manage these stocks, managers need a method of identifying juvenile salmonids by race. In an effort to determine if taxonomic or morphological differences exist between these races, wild juvenile summer and winter steelhead trout (Salmo gairdneri) and wild juvenile spring and fall chinook salmon (Oncorhynchus tshawytscha) from the Rogue River (Oregon) were studied. The goal of the study was to determine if differences in taxonomic characters would allow racial identification of individual fish with 90% accuracy. The wild juvenile summer steelhead trout had significantly fewer vertebrae and larger nuclei, greater average intracircular spacing, and a larger length at first annulus formation of scales than winter steelhead trout. No differences between juvenile summer and winter steelhead trout were found in otolith nuclear diameter, total lipids or fatty acid composition of the muscle tissue. Wild juvenile spring chinook salmon exhibited significantly lower vertebral counts, larger otolith nuclear diameter, greater average intracircular spacing, larger scale nuclei, and a larger first and second band of five intracircular spaces than juvenile fall chinook salmon. Mesentary fat deposition was highly variable between fish from the same streams and was not useful in separating juveniles by race. Although significant differences between races were found for both species, none of these differences were sufficient to allow the racial identification of individual fish with 90% accuracy. It is not known if the differences found were caused by genetic or environmental effects or both. One experiment showed that summer and winter steelhead showed no difference in vertebrae or otolith dimensions when incubated under the same conditions, suggesting that differences found in wild steelhead trout were caused by environmental effects. The lack of distinct phenotypic differences between individual fish of different races may be caused by extensive interbreeding between races of salmonids in the Rogue Basin due to large environmental variability during the spawning season for chinook salmon and steelhead trout. It is also possible that environmental variation in the early life history masked genetic differences between the races.
NOAA Technical Report NMFS CIRC.
Author: Racial Identification of Juvenile Summer and Winter Steelhead and Resident Rainbow Trout (Salmo Gairdneri Richardson)
Author: Brian D. WinterPublisher:
ISBN:
Category : Fishes
Languages : en
Pages : 36
Book Description
Pacific Salmon & their Ecosystems
Author: Deanna J. StouderPublisher: Springer Science & Business Media
ISBN: 1461563755
Category : Science
Languages : en
Pages : 681
Book Description
The symposium "Pacific Salmon and Their Ecosystems: Status and Future Options',' and this book resulted from initial efforts in 1992 by Robert J. Naiman and Deanna J. Stouder to examine the problem of declining Pacific salmon (Oncorhynchus spp.). Our primary goal was to determine informational gaps. As we explored different scientific sources, state, provincial, and federal agencies, as well as non-profit and fishing organizations, we found that the information existed but was not being communicated across institutional and organizational boundaries. At this juncture, we decided to create a steering committee and plan a symposium to bring together researchers, managers, and resource users. The steering committee consisted of members from state and federal agencies, non-profit organizations, and private industry (see Acknowledgments for names and affiliations). In February 1993, we met at the University of Washington in Seattle to begin planning the symposium. The steering committee spent the next four months developing the conceptual framework for the symposium and the subsequent book. Our objectives were to accomplish the following: (1) assess changes in anadromous Pacific Northwest salmonid populations, (2) examine factors responsible for those changes, and (3) identify options available to society to restore Pacific salmon in the Northwest. The symposium on Pacific Salmon was held in Seattle, Washington, January 10-12, 1994. Four hundred and thirty-five people listened to oral presentations and examined more than forty posters over two and a half days. We made a deliberate attempt to draw in speakers and attendees from outside the Pacific Northwest.
Proceedings of the Annual Conference, Southeastern Association of Game and Fish Commissioners
Author: Southeastern Association of Game and Fish CommissionersPublisher:
ISBN:
Category : Fishing
Languages : en
Pages : 880
Book Description