The Life-history and Growth of the Pismo Clam

The Life-history and Growth of the Pismo Clam

Author: Frank Walter Weymouth

Publisher:

Published: 1923

Total Pages: 688

ISBN-13:

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Commercially the Pismo clam (Tivela stultorum)ranks first in importance in California among the clams and third among all the mollusks, being exceeded only by the oyster and the abalone. A second reason for considering this species is that there has been such evidence of depletion as to lead to increasingly more stringent protective laws, all of which have been urged by the residents of the county in which the clam is most abundant. ... An accurate study of the cause and extent of this apparent diminution must await knowledge of at least the fundamental facts of the life history of this clam. ... The more important features are considered to be: the habits, enemies and mortality of the adult; the rate of growth and the factors affecting it; the age at certain significant periods, particularly at sexual maturity and at the time when the legal size is reached; the most common age of clams forming the commercial catch; the season of spawning and the productivity; and the habits, enemies and mortality of the young.


Reproductive Biology and Early Life History of Fishes in the Ohio River Drainage

Reproductive Biology and Early Life History of Fishes in the Ohio River Drainage

Author: Thomas P. Simon

Publisher: CRC Press

Published: 2003-12-29

Total Pages: 229

ISBN-13: 0203497643

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This series fills immense gaps in knowledge of issues related to early life development of fishes in the Ohio basin. Volume III addresses the developmental and morphological issues of catfish and madtoms. This volume describes the characteristics of the Ictaluridae family, and provides a detailed pictorial guide. Subtopics within each species description includes range, distribution, occurrence, spawning, eggs, development, ecology of early life phases, and more. This book serves as both a guide to help identify individual larval fish and as a reference for environmental managers concerned with the overall health of the ecosystem that they are monitoring.