On Estimating Mortality Coefficients in Exploited Fish Populations, Given Two Censuses
- 1 July 1962
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 91 (3) , 283-294
- https://doi.org/10.1577/1548-8659(1962)91[283:oemcie]2.0.co;2
Abstract
Biologists frequently assume that the number of individuals in a “discrete” population follows an exponential relationship with respect to time, at least over the latter part of the life of the members. Such a discrete population may be, for example, a year class of a particular species of fish in a particular body of water. In an exploited population some individuals die from natural causes, and others are harvested. To estimate the extent of natural mortality a common assumption is that total, natural, and fishing mortality coefficients are all constant over the period of study. The present paper differs in that it assumes that only the natural mortality coefficient is constant throughout the period. It assumes that the fishing mortality coefficient is zero when no harvesting occurs, finite and constant when harvests are made over an extended period, and almost infinitely large when large harvests are made in short periods.This publication has 0 references indexed in Scilit: