Management, escapement levels and carrying capacity in some salmon producing systems in Bristol Bay, Alaska
Mathisen O and Poe P. 1983. Management, escapement levels and carrying capacity in some salmon producing systems in Bristol Bay, Alaska. University of Washington, Fisheries Research Institute. Seattle
Salmon management in Bristol Bay has reached a degree of perfection whereby a pre-assigned escapement goal can be reached regardless of levels of exploitation. As a result research is now directed more toward determination of proper escapement goals or escapement sequences. These can be obtained indirectly from estimates of the carrying capacity of the nursery areas based on measurements of primary and secondary production. An empirical apprach to assess escapements through actual counts and relate these to the progeny of fry the first summer after spawning. Relative fry abundance can be determined by the catches made in standardized tow net hauls in the limnetic zone of nursery areas or by acuoustic means. The indicated spawner-fry relationship defines a first measure of optimal escapement level in peak years of a salmon cycle. The consequences of this in an evolutionalry strategy of the species is discussed together with some management implications.