MIGRATIONS AND OTHER PHASES IN THE LIFE HISTORY 
OF THE COD OFF SOUTHERN NEW ENGLAND 
By WILLIAM C. SCHROEDER 
Assistant Aquatic Biologist, United States Bureau of Fisheries 
CONTENTS 
Introduction 
Historical 
Cod migrations in European waters. 
Review of cod tagging off the New 
England coast 
Definition of terms used 
Methods 
Tabulation of the fish tagged 
Significance of a recapture record 
Results 
Migrations of cod between Nantucket 
Shoals and North Carolina 
Evidence of migrations as shown by 
the commercial fishery 
Evidence of migrations as shown by 
tagging experiments 
Cod tagged on Nantucket Shoals, 
Cod tagged in the Woods Hole 
region 
Cod tagged on the Chatham 
grounds 
Evidence that many Rhode Island- 
North Carolina cod come from 
southern Massachusetts 
Southern limit of the cod 
Return migration of cod to New 
England from southern wintering 
grounds 
Migration of cod to the north and east 
of Nantucket Shoals 
Migrations to the Chatham-South 
Channel region 
Scattering of cod to the northward 
and eastward 
Cod which gave no evidence of migrat- 
ing — 
Localization as shown by tagged fish, 
Woods Hole region 
Nantucket Shoals 
Chatham grounds 
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Results — Continued. 
Localization as shown by length fre- 
quency distributions 
Lengths of Nantucket Shoals cod 
in 1923 
Lengths of Nantucket Shoals cod 
in 1924 
Lengths of Nantucket Shoals cod 
in 1925 
Lengths of Nantucket Shoals cod 
in 1926 
Lengths of Nantucket Shoals cod 
in 1927 
Lengths of Nantucket Shoals cod 
in 1928 
Lengths of Nantucket Shoals cod 
in 1929 
Possible causes for the migrations made 
by southern New England cod 
Winter migration 
Summer migration 
Size of the cod population on Nantucket 
Shoals 
Origin of Nantucket Shoals cod 
Local production of cod on Nantucket 
Shoals 
The probable drift of cod fry from 
other regions to Nantucket Shoals. 
Presence of juvenile cod on Nan- 
tucket Shoals 
Immigrations to Nantucket Shoals of 
adult and nearly adult cod 
Age and rate of growth of cod, partic- 
ularly those on Nantucket Shoals. 
Evidence from length frequencies 
Evidence from tagged fish 
Evidence from scale studies 
Resume of conclusions 
Tabulation of recaptures 
Bibliography 
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