MIGRATIONS OF COD 
39 
many of the cod present on the shoals in the spring and early summer were still 
there in the fall, and also that the abundance of the cod did not diminish during any 
of these summers. It is very likely that fewer cod were involved in any one of these 
summer emigrations to the eastward than in any one of the fall migrations to the 
westward. 
This summer migration of cod may be summarized as follows: 
1. A summer emigration of cod from Nantucket Shoals to the Chatham-South 
Channel region occurred each of the years from 1923 to 1925, during which period 
many of the adult fish on the shoals were more than 25 inches in length, while the 
emigration was scarcely noticeable from 1926 to 1928, when the fish averaged below 
this size. 
2. According to tagged-fish records, few Nantucket cod move eastward before 
May. 
3. Scarcely any of the Nantucket cod which summer in the Chatham -South 
Channel region remain there for the winter. Where they go is problematical, but 
many of them may return westward in the fall either to remain on the shoals or to 
continue on to the wintering grounds between Rhode Island and North Carolina. 
A few probably straggle to the northward. 
4. During the summers when this emigration occurred the numbers of cod which 
took part were probably smaller than the numbers of those that went westward each 
fall to spend the winter. 
SCATTERING OF NANTUCKET-CHATHAM COD TO THE NORTHWARD AND EASTWARD 
From a total of 22,228 cod tagged on Nantucket Shoals during 1923-1928 and 
501 tagged on the Chatham grounds during 1927-28 miscellaneous recaptures were 
reported as follows: 
Tagging year, 1923: 7,514 Nantucket cod tagged; 276 recaptured; of these 7, 
or 2.5 per cent, were from miscellaneous localities: 1 on Georges Bank, April, 1923; 
1 off Gloucester, August, 1923; 1 on Jeffreys Ledge, August, 1923; 1 off Plymouth, 
November, 1923; 1 off Hampton Beach, N. H., May, 1924; 1 off Portland, June, 
1923; and 1 on La Have Bank, April, 1925. 
Tagging year, 1924: 3,105 Nantucket cod tagged; 104 recaptured; of these 4, 
or 4 per cent, were from miscellaneous localities: 2 on Georges Bank, November, 
1924, and June, 1926; 1 in Barnstable Bay, May, 1925; and 1 on Stellwagen Bank, 
March, 1925. 
Tagging year 1925: 4,010 Nantucket cod tagged; 143 recaptured. Of these, 11, 
or 7.7 per cent, were from miscellaneous localities: 1 on Georges Bank, December, 
1925; 1 off Highland Light, October, 1926; 3 on Stellwagen Bank, August, 1925, and 
February and July, 1926; 1 off Marblehead, May, 1926; 1 in Ipswich Bay, May, 
1927; 1 in Salem Harbor, July, 1925; 1 off Monhegan, September, 1925; and 2 off 
Mount Desert, February, 1926, and fall of 1927. 
Tagging year 1926: 1,606 Nantucket cod tagged; 18 recaptured. Of these, 1 fish, 
or 5.5 per cent, was retaken on Georges Bank in May, 1927. 
Tagging year 1927 : 5,020 Nantucket cod tagged; 149 recaptured. Of these, 5, or 
3.4 per cent, were from miscellaneous localities, as follows: 3 on Georges Bank, 
December, 1927, and September and October, 1928; 1 on Stellwagen Bank, November, 
1927; and 1 off Nahant, April, 1928. On the Chatham ground 475 cod were tagged 
of which 16 were recaptured, 1 of them being in Ipswich Bay in May, 1928. 
