Excerpt from Blood Types in Pacific Salmon One of the most important problems in fishery biology is recognition of races or reproductively isolated subpopulations, of fishes. Since there may be little or no interbreeding or recruitment between such populations, successful regulation or management of fishery resources must be con ducted in such a way as to recognize their independence. 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.