Abstract

The reproduction situation of chum salmon in Alaska has not been studied because of its lowest economical value and small size of stock. However, it has a important meaning to estimate the effect of artificial propagation for chum salmon in Japan and also it is neces-sary to know the situation of fishery management for chum salmon in Alaska. In this paper, the reproduction situations of chum salmons both in Central and Southeast-ern Alaska are studied using Ricker's formula (R=aEa-bE), in which the numbers on es-capements (E) and returns (R) are estimated by the catch statistics from 1920 to 1961 under the adequate assumption of fishing rate, which is 0.5 for Central Alaska and 0.5-0.65 for Southeastern Alaska. Following tables and figures resulted from above estimations show that 1) the number of returns per spawner in MSY is about 3.2-3.6 fishes, and 2) the reproduction situation in South-eastern Alaska has fallen since 1950, while 3) the recent exploitation in Central Alaska does not realize full utilization.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.