An Age-Structured Model of Fish Population Enhancement

Abstract

The addition of young fish to the ocean to enhance depleted populations and to compensate for the exploitation of larger, commercially valuable animals is an alluring idea. It is also not a new idea, having been practiced since the development of rearing techniques for various species of fish in the nineteenth century (Shelbourne 1964). Many of the marine laboratories in both the United States and Europe were, in fact, established as fish hatcheries for the propagation and release of larval and juvenile fish to rectify a perceived demise of the local fish populations (Galtsoff 1962; Solemdal et al. 1984; Kirk 1987).

Traditionally, the marine biologists involved in management of fish stocks have not been confronted with the question of economic return. With the introduction of stock enhancement and especially sea ranching the situation is quite different. A. Hallenstvedt, from Management of Enhanced Stocks: Social, Economic and Access Issues