Download or read book Standardizing the Southern Gulf of St Lawrence Bottom trawl Survey Time Series Adjusting for Changes in Research Vessel Gear and Survey Protocol written by Canada. Department of Fisheries and Oceans and published by Moncton, N.B. : Fisheries and Oceans. This book was released on 2003 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Calibration of Bottom Trawl Survey Vessels written by G. Mark Fowler and published by . This book was released on 2009 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adjustments to calibrate fish and invertebrate abundance estimates between two research survey vessels were determined using mixed-effects and fixed-effects modelling. The fixed-effects model assumes equal probability of a fish being available for capture between the two vessels for a given paired tow set, while the mixed-effects model assumes equal probability over the population of sets, including an estimate of within-set variability as random error. The mixed-effects approach appeared superior to the fixed-effects approach, being better able to resolve the high variability between sets characteristic of the stratified-random survey design in which the calibrartion experiment was conducted. Differences in catchability with length of animals was pervasive, the greatest differences in catchability between vessels being associated with the smallest animals. The influence of length on catchability was best portrayed as a curilinear relationship, as catchability tended to plateau for animals over about 26cm. For some species catchabilities between vessles differed according to the time of day and depth of a tow, though in most cases the differences were of fairly small magnitude.
Download or read book Standardizing the Southern Gulf of St Lawrence Bottom Trawl Survey Time Series written by Hugues Pascal Benoît and published by . This book was released on 2006 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Technical Report of Fisheries and Aquatic Sciences written by and published by . This book was released on 2009 with total page 34 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 2013 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Results from the 2011 Sentinel Bottom trawl Survey in the Southern Gulf of St Lawrence and Comparisons with Previous 2003 to 2010 Surveys written by Luc Savoie and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Northeast Fisheries Science Center Bottom Trawl Survey Protocols for the NOAA Ship Henry B Bigelow written by Philip J. Politis and published by . This book was released on 2014 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This document describes the standard operational protocols for conducting the Northeast Fisheries Science Center spring and autumn Multispecies Bottom Trawl Survey aboard the NOAA Ship Henry B. Bigelow. This manual documents current survey protocols and standard sampling gear implemented in spring 2009 after the 2008 survey calibration with the NOAA Ship Albatross IV and the NOAA Ship Henry B. Bigelow. It is intended to serve as a reference manual to ensure survey standardization and aid in the training of new personnel"--Executive summary.
Download or read book Evaluation of the Utility of Summer Trawl Surveys 1990 to 1994 in the Shediac Valley NAFO Unit Area 4Tl as an Index of Pre recruit Abundance for Southern Gulf of St Lawrence Cod written by and published by . This book was released on 1995 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper evaluates the potential of a juvenile cod survey as an independent index of pre-recruiting year class strength of southern Gulf of St. Lawrence cod. The evaluation is based on five surveys conducted with a bottom trawl in the Shediac Valley area of the southern Gulf in the summers of 1990 to 1994. Numbers per tow at age for ages 1 to 9 were obtained for all five years of the survey. Two types of analyses were used to attempt to evaluate the utility of the surveys as an index of year class strength: correlation analysis and application of two multiplicative models, an age & year class model and an age, year class, stratum, and age-stratum interaction model.
Download or read book A Review of Current International Approaches to Standardisation and Calibration in Trawl Survey Time Series written by Neil W. Bagley and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the North Pacific Symposium on Invertebrate Stock Assessment and Management written by National Research Council Canada and published by NRC Research Press. This book was released on 1998 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a symposium that focused on new, innovative evaluation of the implications and needs for changing management approaches and demands in invertebrate fishery science. Species covered in the presentations include crustaceans, gastropods, echinoderms, and bivalves. Presentations are organized in the following subject areas: assessment of abundance and related parameters; growth, mortality, and yield per recruit; spatial pattern and its implications; the fishing process; population dynamics; the fishery as a selective force; invertebrate fisheries management; and regional perspectives from the north Pacific. The proceedings conclude with a symposium overview.
Download or read book Improving Fish Stock Assessments written by National Research Council and published by National Academies Press. This book was released on 1998-02-27 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ocean harvests have plateaued worldwide and many important commercial stocks have been depleted. This has caused great concern among scientists, fishery managers, the fishing community, and the public. This book evaluates the major models used for estimating the size and structure of marine fish populations (stock assessments) and changes in populations over time. It demonstrates how problems that may occur in fisheries dataâ€"for example underreporting or changes in the likelihood that fish can be caught with a given type of gearâ€"can seriously degrade the quality of stock assessments. The volume makes recommendations for means to improve stock assessments and their use in fishery management.
Download or read book Evaluation of the Utility of Summer Trawl Surveys 1990 to 1994 in the Shediac Valley NAFO Unit Area 4TI as an Index of Pre recruit Abundance for Southern Gulf of St Lawrence Cod written by Canada. Department of Fisheries and Oceans and published by Moncton, N.B. : Department of Fisheries and Oceans. This book was released on 1995 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Method to Reduce Survey Bottom Trawl Variability written by A. Engas and published by . This book was released on 1991 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Workshop on Survey Trawl Mensuration written by and published by . This book was released on 1993 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the workshop, covering survey trawl mensuration research at Norwegian, Scottish, Icelandic, Swedish, and United States research institutes and the four federal Department of Fisheries and Oceans Atlantic Region stations; the sources of bias and variance associated with survey trawl efficiency; applications of trawl mensuration equipment and data to improve survey methodology and survey estimates; and standardization of trawl survey protocols. Recommendations were included.
Download or read book Factors Affecting Variability of Research Vessel Trawl Surveys written by C. J. Byrne and published by . This book was released on 1981 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Le Golfe Du Saint Laurent petit Oc an Ou Grand Estuaire written by Canada. Department of Fisheries and Oceans and published by Peches Et Oceans Direction Generale Des Communications = Fisheries and Oceans Communications Dir. This book was released on 1991 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a workshop, the scientific reviews and the contributed papers presented at the symposium. The document presents a brief historical summary of marine research in the Gulf; reports the discussions, conclusions and recommendations of the different working groups on oceanography (physics, biology, chemistry and sedimentology) and on the fishery (fish and invertebrates); then presents the discussions of each multidisciplinary working group, centered around how the St. Lawrence system may be used as a natural laboratory which will contribute to the solution of major long-term problems of conservation of natural resources and of the quality of the environment.
Download or read book Definici n Y Clasificaci n de Las Diversas Categor as de Artes de Pesca written by C. Nédélec and published by . This book was released on 1990 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:
