Author: Frank Walter Weymouth
Publisher:
ISBN:
Category : Clams
Languages : en
Pages : 688
Book Description
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.
The Life-history and Growth of the Pismo Clam
Author: Frank Walter Weymouth
Publisher:
ISBN:
Category : Clams
Languages : en
Pages : 688
Book Description
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.
Publisher:
ISBN:
Category : Clams
Languages : en
Pages : 688
Book Description
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.
The Life History of Leuresthes Tenuis, an Atherine Fish with Tide Controlled Spawning Habits
Author: Frances Naomi Clark
Publisher:
ISBN:
Category : Atheriniformes
Languages : en
Pages : 72
Book Description
Publisher:
ISBN:
Category : Atheriniformes
Languages : en
Pages : 72
Book Description
The Structure and Growth of the Scales of the Squeteague and the Pigfish as Indicative of Life History
Author: Harden Franklin Taylor
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 70
Book Description
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 70
Book Description
Migrations and Other Phases in the Life History of the Cod Off Southern New England
Author: William Charles Schroeder
Publisher:
ISBN:
Category : Codfish
Languages : en
Pages : 144
Book Description
Publisher:
ISBN:
Category : Codfish
Languages : en
Pages : 144
Book Description
Contributions to the Life Histories of Sciaenidae of the Eastern United States Coast
Author: William Welsh Welsh
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 72
Book Description
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 72
Book Description
Life History of the Lake Herring (Leucichthys Artedi Le Sueur) of Lake Huron as Revealed by Its Scales
Author: John Van Oosten
Publisher:
ISBN:
Category : Herring
Languages : en
Pages : 198
Book Description
Publisher:
ISBN:
Category : Herring
Languages : en
Pages : 198
Book Description
Special Scientific Report
Biological Report
Coregonid Fishes of the Great Lakes
Author: Walter Koelz
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 1082
Book Description
Publisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 1082
Book Description
Bulletin of the United States Bureau of Fisheries
Author: United States. Bureau of Fisheries
Publisher:
ISBN:
Category : Fish culture
Languages : en
Pages : 556
Book Description
Publisher:
ISBN:
Category : Fish culture
Languages : en
Pages : 556
Book Description