Spawning Escapement Of Okanogan River Blueback Salmon Oncorhynchus Nerka 1957 PDF Download

Excerpt from Spawning Escapement of Okanogan River Blueback Salmon (Oncorhynchus Nerka), 1957 The 1957 return of blueback was of special interest since the he's were the progeny of the 1953 escapement which was one of the largest in recent years. The most unusual feature of the 1953 run was that over 86 percent of the Okanogan spawners were 3-year-old fish whose sex ratio of males to females was The bulk of these 3-year-old fish escape the fishery and continue to the Okanogan where in normal years they comprise about 22 percent of the spawning population. These small fish seem to be peculiar to the Okanogan and are seldom encountered in the other two systems. Table 6 demonstrates the occurrence of 3-year-old Columbia River blueback for the last 7 years. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.