Results 221 to 230 of about 38,641 (266)

Statistical Catch-at-Age Methods

1992
In the last chapter, we saw how historical stock sizes and fishing mortality rates could be estimated from catch-at-age data and an assumed natural mortality rate using vpa. There are two major problems with vpa: it can give unreliable estimates for cohorts that have not completely disappeared from the fishery, and it requires an assumption about the ...
Ray Hilborn, Carl J. Walters
openaire   +1 more source

Improving fishery catch statistics for Lake Victoria

Aquatic Ecosystem Health & Management, 2003
The fisheries of Lake Victoria are highly dispersed and catch statistical information is insufficient for supporting management. Catch assessment surveys for the three riparian countries were found to be weak or inadequate and a strategy for improving this source of information is proposed.
I. G. Cowx, M. van der Knaap, L. I. Muhoozi, A. Othina   +3 more
openaire   +1 more source

Using Catch Statistics to Investigate Effects of Seismic Activity on Fish Catch Rates

2012
Norway has been a petroleum nation for several decades, with most of its offshore activities originally concentrated in the North Sea. As these reserves diminish, focus is shifting to areas further north, some of which, particularly the Lofoten/Vesteralen area, are crucial for the reproduction of major fish stocks such as Gadus morhua (northeastern ...
Aud, Vold, Sven, Løkkeborg, Maria M, Tenningen   +2 more
openaire   +2 more sources

A simple statistical method for catch comparison studies

Fisheries Research, 2009
For analysing catch comparison data, we propose a simple method based on Generalised Linear Mixed Models (GLMM) and use polynomial approximations to fit the proportions caught in the test codend. The method provides comparisons of fish catch at length by the two gears through a continuous curve with a realistic confidence band.
Holst, René, Revill, Andrew S
openaire   +2 more sources

Is catch proportional to nominal effort? Conceptual, fleet dynamic, and statistical considerations in catch standardization

Canadian Journal of Fisheries and Aquatic Sciences, 2019
Often, catch-per-unit-effort (CPUE) standardizations are used to reflect fish abundance. This implies that catch is directly proportional to effort. We examine this using 78 reported catch and effort series in a meta-analysis, correcting for errors-in-variables in the relationship.
Aljafary, Michelle, Gillis, Darren M, Comeau, Peter   +2 more
openaire   +1 more source

Prediction of fish catch in the Danube River based on long-term variability in environmental parameters and catch statistics

Science of The Total Environment, 2017
The effects of physical factors on fish catch in the Serbian part of the Danube River were studied for period of six decades. The data on total catch for the Danube River from river kilometre 845 to river kilometre 1433 were collected from Statistical Office of the Republic of Serbia, while water level and water temperature data were collected from 16 ...
Smederevac-Lalić, Marija M., Kalauzi, Aleksandar J., Regner, Slobodan B., Lenhardt, Mirjana, Naunović, Zorana Z., Hegediš, Aleksandar E.   +5 more
openaire   +5 more sources

Six Years of Catch Statistics on Yellowstone Lake

Transactions of the American Fisheries Society, 1957
Abstract The U. S. Fish and Wildlife Service collected catch statistics on Yellowstone Lake and adjacent waters from 1950 to 1955 as part of an investigation on the status of the cutthroat trout fishery and the fish populations. Methods for estimating numbers of fishermen, hours of effort, and catch, were developed for each unit of the fishery and were
openaire   +1 more source

Statistical analysis of catch-at-age data with correlated errors

Canadian Journal of Fisheries and Aquatic Sciences, 1995
We extend the statistical model used to estimate abundance from commercial catch-at-age data for many of the major commercial fish species in the world. The model we consider combines commercial catch-at-age data and research survey estimates of fish abundance; we extend the model to allow correlated errors among ages within a year for the survey ...
Ransom A. Myers, Noel G. Cadigan
openaire   +1 more source

A Method of Collecting Statistics of Marine Sport Catches in California

Transactions of the American Fisheries Society, 1933
(1933). A Method of Collecting Statistics of Marine Sport Catches in California. Transactions of the American Fisheries Society: Vol. 63, No. 1, pp. 332-337.
G. H. Clark, Richard Croker
openaire   +1 more source

Evaluating the performance of a multispecies statistical catch-at-age model

Canadian Journal of Fisheries and Aquatic Sciences, 2013
Predation is a substantial source of mortality that is a function of the abundance of predator and prey species. This source of mortality creates a challenge of incorporating species interactions in statistical catch-at-age models in a way that accounts for the uncertainty in input data, parameters, and results.
Curti, Kiersten L., Collie, Jeremy S., Legault, Christopher M., Link, Jason S.   +3 more
openaire   +2 more sources