Unutilized Fishes and Their Relation to the Fishing Industries (Classic Reprint)

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Excerpt from Unutilized Fishes and Their Relation to the Fishing Industries The destruction of food fishes by fishes of little or no commercial value is a subject of obvious importance to the fishing industries. To preserve for his own uses the species he values, it becomes necessary for man to control the depredations of his rivals. Under normal conditions the balance among the different forms of life is maintained by natural laws. Where great destructive forces are at work upon a species that species will be found to be endowed with great powers of reproduction. The lobster, for example, wholly defenseless in its early stages, and even when mature the prey of a host of enemies, is able to perpetuate itself because of its enormous fecundity, there being a biennial production of about 15, 000 eggs by each mature female lobster. The smooth dogfish, on the other hand, a most destructive enemy of the lobster but itself comparatively free from enemies, produces from four to a dozen young at a time, and these are practically adult in form at birth. The natural balance, however, is seriously disturbed by man, for whose purposes the supply of one species is exhaustively drawn upon, while another, perhaps destructive, form undergoes no diminution. To offset the drain upon the valuable species, close seasons have been created to afford them protection during the breeding periods, fish hatcheries have been established to replenish their numbers, and sometimes the destruction of their natural enemies has been sought by means of bounties or through the introduction of parasites. Effective methods of lessening the destructiveness of the useless marauders, however, are the important factor lacking in present conditions. While the struggle for existence has grown constantly more severe for the lobster, which has man as a new enemy, the smooth dogfish has continued unmolested, and thus increased in numbers. And so with the other commercial species and their nonvalued enemies. With the fish culturist's aid and the legislator's care a species may be able to maintain itself even against the combined agencies of its natural enemies and man, but the struggle is increasingly difficult, and it is ultimately hopeless in some cases. 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.