Download or read book Age Determination Manual of the Alaska Fisheries Science Center Age and Growth Program written by Mary Elizabeth Matta and published by . This book was released on 2012 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Age and Growth Program at the Alaska Fisheries Science Center is tasked with providing age data in order to improve the basic understanding of the ecology and fisheries dynamics of Alaskan fish species. The primary focus of the Age and Growth Program is to estimate ages from otoliths and other calcified structures for age-structured modeling of commercially exploited stocks; however, the program has recently expanded its interests to include numerous studies on topics ranging from age estimate validation to the growth and life-history of non-target species. Because so many applications rely upon age data and particularly upon assurances as to their accuracy and precision, the Age and Growth Program has developed this practical guide to document the age determination of key groundfish species from Alaskan waters. The main objective of this manual is to describe techniques specific to the age determination of commercially and ecologically important species studied by the Age and Growth Program. The manual also provides general background information on otolith morphology, dissection, and preparation, as well as descriptions of methods used to measure precision and accuracy of age estimates. This manual is intended not only as a reference for age readers at the AFSC and other laboratories, but also to give insight into the quality of age estimates to scientists who routinely use such data.
Download or read book Age Determination Manual of the Alaska Fisheries Science Center Age and Growth Program written by and published by . This book was released on 2012 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Age and Growth Program at the Alaska Fisheries Science Center is tasked with providing age data in order to improve the basic understanding of the ecology and fisheries dynamics of Alaskan fish species. The primary focus of the Age and Growth Program is to estimate ages from otoliths and other calcified structures for age-structured modeling of commercially exploited stocks; however, the program has recently expanded its interests to include numerous studies on topics ranging from age estimate validation to the growth and life-history of non-target species. Because so many applications rely upon age data and particularly upon assurances as to their accuracy and precision, the Age and Growth Program has developed this practical guide to document the age determination of key groundfish species from Alaskan waters. The main objective of this manual is to describe techniques specific to the age determination of commercially and ecologically important species studied by the Age and Growth Program. The manual also provides general background information on otolith morphology, dissection, and preparation, as well as descriptions of methods used to measure precision and accuracy of age estimates. This manual is intended not only as a reference for age readers at the AFSC and other laboratories, but also to give insight into the quality of age estimates to scientists who routinely use such data.
Download or read book Age Determination Manual of the Alaska Fisheries Science Center Age and Growth Program written by Mary Elizabeth Matta and published by . This book was released on 2012 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Age and Growth Program at the Alaska Fisheries Science Center is tasked with providing age data in order to improve the basic understanding of the ecology and fisheries dynamics of Alaskan fish species. The primary focus of the Age and Growth Program is to estimate ages from otoliths and other calcified structures for age-structured modeling of commercially exploited stocks; however, the program has recently expanded its interests to include numerous studies on topics ranging from age estimate validation to the growth and life-history of non-target species. Because so many applications rely upon age data and particularly upon assurances as to their accuracy and precision, the Age and Growth Program has developed this practical guide to document the age determination of key groundfish species from Alaskan waters. The main objective of this manual is to describe techniques specific to the age determination of commercially and ecologically important species studied by the Age and Growth Program. The manual also provides general background information on otolith morphology, dissection, and preparation, as well as descriptions of methods used to measure precision and accuracy of age estimates. This manual is intended not only as a reference for age readers at the AFSC and other laboratories, but also to give insight into the quality of age estimates to scientists who routinely use such data.
Download or read book Stock Identification Methods written by Steven X. Cadrin and published by Academic Press. This book was released on 2013-10-04 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stock Identification Methods, 2e, continues to provide a comprehensive review of the various disciplines used to study the population structure of fishery resources. It represents the worldwide experience and perspectives of experts on each method, assembled through a working group of the International Council for the Exploration of the Sea. The book is organized to foster interdisciplinary analyses and conclusions about stock structure, a crucial topic for fishery science and management. Technological advances have promoted the development of stock identification methods in many directions, resulting in a confusing variety of approaches. Based on central tenets of population biology and management needs, this valuable resource offers a unified framework for understanding stock structure by promoting an understanding of the relative merits and sensitivities of each approach. - Describes 18 distinct approaches to stock identification grouped into sections on life history traits, environmental signals, genetic analyses, and applied marks - Features experts' reviews of benchmark case studies, general protocols, and the strengths and weaknesses of each identification method - Reviews statistical techniques for exploring stock patterns, testing for differences among putative stocks, stock discrimination, and stock composition analysis - Focuses on the challenges of interpreting data and managing mixed-stock fisheries
Download or read book Marine Freshwater Research written by and published by . This book was released on 2016 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Species and Age of Fish Aboard the Cyi Yang No 1 as Determined from Scales Scraped from the Freezers Hold and Fishing Gear written by John H. Helle and published by . This book was released on 1989 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 2012 with total page 828 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Latitude Crabs written by Alaska Sea Grant College Program and published by Computer Technology Research Corporation. This book was released on 1995 with total page 736 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings builds on knowledge brought together during four previous north latitude crab symposia, and has recommendations for future crab research. Forty-eight papers were presented at the 1995 symposium in Anchorage, Alaska. Research is included from Argentina, Australia, Canada, Japan, Norway, Russia, and the United States. Long-term goals of the symposium are to better conserve the resource, strengthen the industry, and provide accessible healthful protein to the consumer. Winner of a Gold Award for editing, Agricultural Communicators in Education.
Download or read book Trends in Fisheries and Fishery Resources Associated with the Monterey Bay National Marine Sanctuary from 1981 2000 written by Richard M. Starr and published by . This book was released on 2002 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Technical Report written by and published by . This book was released on 2000 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Female Sablefish Age at maturity in Alaska Applicable to Stock Assessment written by Cara J. Rodgveller and published by . This book was released on 2017 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report is a summary of results from sablefish maturity studies conducted in December 2011, July through August 2015, and December 2015. More thorough investigations and descriptions of these studies have been published or are in preparation for publication. Included here are descriptions of ovarian development, definitions used for microscopic and macroscopic maturity classification, and age-at-maturity results that may be applicable to sablefish stock assessment in Alaska. In winter 2011 and 2015, microscopic methods were used to categorize maturity. In summer 2015, maturity was classified three ways: macroscopically atsea by several scientists, macroscopically from photographs by a single expert observer (standardized macroscopic), and microscopically (with histology slides). Macroscopic methods, used during the summer, resulted in estimates of the age-at-50% maturity (A50) that were younger than histological and standardized macroscopic methods. Because the macroscopic method could not be validated by the microscopic method, classifications made at-sea may not accurately represent the current oocyte development. For the summer months, oocytes were in later stages of development in the second half of August and so this time period provides the most accurate predictions whether fish will spawn in the coming season. December proved to be an ideal time to sample for maturity because fish that would spawn were in advanced stages of vitellogenesis. In winter 2011, skipped spawning was more prevalent than in the summer or winter of 2015. For the 2011 samples, incorporating skip spawning into age-at-maturity models had a large effect on age-at-maturity. [doi:10.7289/V5AFSC-PR-2017-12 (https://doi.org/10.7289/V5/AFSC-PR-2017-12)]
Download or read book Conservation and Adaptive Management of Seamount and Deep sea Coral Ecosystems written by Robert Y. George and published by Rosenstiel School of Marine and Atmospheric Science University of Miami. This book was released on 2007 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Marine Mammals Ashore written by Joseph R. Geraci and published by National Aquarium in Baltimore. This book was released on 2005 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive manual for understanding and carrying out marine mammal rescue activities for stranded seals, manatees, dolphins, whales, or sea otters.
Download or read book Protocol for Estimating Age of Weathervane Scallops Patinopecten Caurinus in Alaska written by Christopher E. Siddon and published by . This book was released on 2017 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Age determination is an essential component to many fisheries stock assessments that provide the foundation for sound fisheries management. Although stock assessment models that include age data are generally an improvement over length-based models, errors in age data can have serious repercussions on fisheries management. Thus, a standardized methodology and formal quality control measures are essential. Here we present a standardized protocol to assess the age of weathervane scallops Patinopecten caurinus collected by the Alaska Department of Fish and Game's statewide scallop research and observer programs. These methods and analyses also provide measures and thresholds to test for precision (percent agreement and mean CV) and bias (Bowker's and Evans-Hoenig tests of symmetry) in age estimates, as well as quality control mechanisms for a long-term scallop age assessment program.
Download or read book Age at maturity and Fecundity of Female Sablefish Sampled in December of 2011 and 2015 in the Gulf of Alaska written by Cara J. Rodgveller and published by . This book was released on 2018 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: We compared published results of the age-at-maturity and relative fecundity of female sablefish Anoplopoma fimbria sampled just prior to the spawning season nearby Kodiak Island in 2011 to results from a study in the same geographic area in 2015. The rate of skip-spawning was higher in 2011 (21%) than in 2015 (6%) and, therefore, in 2011 there were larger effects on the estimates of age-at-maturity when skip-spawning fish were classified as mature or immature than in 2015. When skip-spawning fish were classified as mature, the age-at-50% maturity in 2011 was 0.5 years younger than in 2015. When skip-spawning fish were classified as immature, ageat-50% maturity was 1.9 years older in 2011 than in 2015. Generally, skip-spawning was at ages where a portion of the fish were not yet mature (i.e., the age at which fish were estimated to be
Download or read book Calculation of the Geographic Area Sizes Used to Create Population Indices for the Alaska Fisheries Science Center Longline Survey written by Katy Beth Echave and published by . This book was released on 2013 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The purpose of this document is to 1) provide a historical accounting of previous methods used to generate the current geographic area measurements, 2) provide comparable geographic area measurements for the full extent of the AFSC longline survey using modern GIS technology and more recent bathymetric data and 3) calculate area sizes for the shallow stratum 151-200 m, where sizes are not currently available. We present methodology used to create new area measurements using a single source of bathymetric data and ArcGIS® software. Results from these calculations are presented with the historical estimates for comparison. Finally, we include a series of maps for each of the management areas highlighting areas where definitions of area boundaries were difficult to interpret and redefine, such as gullies and passes"--Introduction.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1978 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
