Abstract
An age structured production model of multicohort fish population dynamics based on the mean metabolic state of individuals and the average abundance of year-classes is proposed. The model allows variations in life stage basal metabolic rates by parameterizing their effects on total population abundance through a mortality function which itself depends upon an individual's status relative to an optimal metabolic state. The metabolic equations are derived in terms of age-specific individual weight. The interaction of individual status and intraspecific competition is allowed by coupling the metabolic equations for growth to those for population abundance. This coupling yields a second-order nonlinear equation in abundance or biomass. In model simulations, (1) increased numbers of cohorts decreased the stability of population biomass, (2) numerically 'strong' year- classes damped and sometimes caused collapse of proximal age-classes, (3) exploitation reduced competitive interactions and increased model stability, and (4) increases in natural mortality introduced greater recruitment variability. The transitional and steady state behaviors of the multicohort model are explored and compared to traditional fishery management models for a small pelagic species, northern anchovy Engraulis mordax.
| Original language | English |
|---|---|
| Pages (from-to) | 343-363 |
| Number of pages | 21 |
| Journal | Transactions of the American Fisheries Society |
| Volume | 125 |
| Issue number | 3 |
| State | Published - Dec 1 1996 |
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ASJC Scopus subject areas
- Aquatic Science
- Earth and Planetary Sciences(all)
- Environmental Science(all)
Cite this
A multicohort stock production model. / Ault, Jerald S; Olson, Donald.
In: Transactions of the American Fisheries Society, Vol. 125, No. 3, 01.12.1996, p. 343-363.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - A multicohort stock production model
AU - Ault, Jerald S
AU - Olson, Donald
PY - 1996/12/1
Y1 - 1996/12/1
N2 - An age structured production model of multicohort fish population dynamics based on the mean metabolic state of individuals and the average abundance of year-classes is proposed. The model allows variations in life stage basal metabolic rates by parameterizing their effects on total population abundance through a mortality function which itself depends upon an individual's status relative to an optimal metabolic state. The metabolic equations are derived in terms of age-specific individual weight. The interaction of individual status and intraspecific competition is allowed by coupling the metabolic equations for growth to those for population abundance. This coupling yields a second-order nonlinear equation in abundance or biomass. In model simulations, (1) increased numbers of cohorts decreased the stability of population biomass, (2) numerically 'strong' year- classes damped and sometimes caused collapse of proximal age-classes, (3) exploitation reduced competitive interactions and increased model stability, and (4) increases in natural mortality introduced greater recruitment variability. The transitional and steady state behaviors of the multicohort model are explored and compared to traditional fishery management models for a small pelagic species, northern anchovy Engraulis mordax.
AB - An age structured production model of multicohort fish population dynamics based on the mean metabolic state of individuals and the average abundance of year-classes is proposed. The model allows variations in life stage basal metabolic rates by parameterizing their effects on total population abundance through a mortality function which itself depends upon an individual's status relative to an optimal metabolic state. The metabolic equations are derived in terms of age-specific individual weight. The interaction of individual status and intraspecific competition is allowed by coupling the metabolic equations for growth to those for population abundance. This coupling yields a second-order nonlinear equation in abundance or biomass. In model simulations, (1) increased numbers of cohorts decreased the stability of population biomass, (2) numerically 'strong' year- classes damped and sometimes caused collapse of proximal age-classes, (3) exploitation reduced competitive interactions and increased model stability, and (4) increases in natural mortality introduced greater recruitment variability. The transitional and steady state behaviors of the multicohort model are explored and compared to traditional fishery management models for a small pelagic species, northern anchovy Engraulis mordax.
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UR - http://www.scopus.com/inward/citedby.url?scp=0030302936&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0030302936
VL - 125
SP - 343
EP - 363
JO - Transactions of the American Fisheries Society
JF - Transactions of the American Fisheries Society
SN - 0002-8487
IS - 3
ER -