Density-dependent marine processes in North Pacific salmonids: lessons for experimental design of large-scale manipulations of fish stocks

Density-dependent growth and survival processes occur within and among stocks and species of Pacific salmon (Oncorhynchus spp.) and other fishes. These processes, in addition to numerical responses of natural predators and fishermen, can generate lower benefits than expected from the increases in abundance that result from extensive mariculture. Benefit/cost analyses of proposed mariculture programmes should, therefore, take such processes into account. As well, such programmes should be designed as rigorous large-scale experiments so that managers can: (1) distinguish whether a change in stock abundance (or lack thereof) is due to mariculture or to changes in some natural processes such as ocean productivity, and (2) identify appropriate remedial actions, should they become necessary.

This article is part of Marine Science Symposia Volume 192 - "The ecology and management aspects of extensive mariculture". To access other articles from this volume, please use the link to the volume on the upper right hand side.