The Quest for a Biological Optimum Escapement for Sockeye Salmon

摘要

A study was made of the way in which sockeye salmon Oncorhynchus nerka runs are managed in North America by regressing escapement on catch. The intercept is a provisional estimate of the escapement needed to maintain the run under the prevailing management system. Since they are very close to stated escapement goals, managers are today able to secure a preset number of spawners. In order to preserve bio diversity, management must consider other attributes in addition to numbers, like spatial distribution of the escapement and conservation of minor age groups. The fishing power of the fleet is high enough to remove all salmon present in a district during a long fishing period. An alternative strategy would be continuous fishing throughout the seasonwith sufficient reduction in units of gear. Optimum escapement goals cannot be based solely on the needs of the commercial fishery; but other user groups must be considered.