Behavior of Displaced Adult Pink Salmon

Abstract

Abstract Studies to show whether pink salmon (Oncorhynchus gorbuscha, Walbaum) will repeat their original choice of spawning area when captured and transported to another location were done in Olsen Creek, Prince William Sound, Alaska, in 1961, 1962, and 1963. Fish to be displaced were anesthetized with MS-222 (except in 1961 when no anesthesia was used) and marked with Petersen disk tags. Equal numbers of control fish were treated in an identical manner and left at the donor site. In 1961, 100 pink salmon were displaced from Olsen Creek beyond the entrance of the bay, a distance of more than 3 miles from the creek mouth. Of the 54 fish accounted for, 91% returned to Olsen Creek. In 1962 and 1963, the displacements were confined to Olsen Bay. Fish displaced “on-route” achieved a higher rate of return than fish displaced “off-route.” Further, under conditions of extremely low stream flow, displaced fish did not return to their original choice of spawning area. When stream flows were normal or high, they sh...