FISHES OF CHESAPEAKE BAY 
157 
Color green to red brown above and on sides; pale below; sides and back with green, brown, 
or reddish irregular spots, usually of one color on any one fish; spots sometimes extending on dorsal 
fins; lateral line pale; fins usually the same as ground color. 
This species was not seen by us in the field. The above description is based on five specimens, 
350 to 497 millimeters (about 14 to 20 inches) in length, caught off Gay Head, Mass. The color 
of the cod is very variable. Out of 25,000 cod observed by the junior author during fish-tagging 
operations, the colors ranged from pale green to deep red brown and bright red. The greenish 
cod have dark green or reddish spots, while the reddish cod usually have dark brown spots. We 
have seen several specimens, as large as 30 inches, that were colored bright red everywhere on body, 
head, and fins, including the lower parts. 
The fin rays vary in number. A large series of Gulf of Maine fish examined by Welsh gave 
the following variation: First dorsal, 13 to 16; second dorsal, 19 to 24; third dorsal, 18 to 21; first 
anal, 20 to 24; second anal, 17 to 22. (Bigelow and Welsh, 1925 p. 410.) The cod is distinguished 
by its three dorsal fins, two anal fins, barbel at the chin, projecting upper jaw, nearly square tail, 
vent under the beginning of the second dorsal, and by the pale (not black) lateral line. 
The cod is typically a bottom feeder but at times rises to the surface in pursuit of schools of 
small fish and squid. The cod is omnivorous, including in its diet many species of fish, mollusks, 
crustaceans, worms, echinoderms (chiefly brittle stars), as well as hydroids and algae. Many foreign 
objects have been recorded from cod stomachs, including pieces of metal, gravel, wood, rope, and 
rubber, and fragments of clothing. Aboard the Halcyon in 1925, fishing 35 miles from shore, we 
were surprised to find an empty cigarette container in a cod stomach. It probably had been thrown 
from a vessel and was seized by the cod because of the bright tinfoil with which it was wrapped. 
However, the cod does have a preference for certain foods, among which are rock crabs (Cancer), 
hermit crabs, sea clams (Mactra), cockles (Lunatia), lobsters, brittle stars, blood worms (Nereis), 
sand launces (Ammodytes), and young herring (Clupea). The chief baits used in the western 
Atlantic for catching cod are fresh or frozen herring, squid, cockles, and clams ( Mya arenaria). 
The scales of cod form a good index for determining age, but this study is rendered complex 
because of the protracted spawning season (fall to spring) and because of the fish’s wide distribu- 
tion, wherein growth is more rapid in some localities than in others European cod average 5, 8.3, 
and 12.2 inches in length for the first, second, and third years, respectively. Bay of Fundy cod 
average 5.7, 14.2, and 19.6 inches, and we find the size of Nantucket Shoals cod to be about 8, 15, 
and 23 inches for the first, second, and third years, respectively. 
Spawning takes place along our coast from October to June, the height of the season, how- 
ever, occurring during the winter. Spawning begins earlier in the southern part of the range than 
farther north and also ends correspondingly earlier. An inshore migration of spawning fish has 
been noticed. The eggs of the cod are buoyant, transparent, 1.16 to 1.82 millimeters in diameter 
(Bigelow and Welsh, 1925, p. 428), and the incubation period extends over about 10 to 11 days at 
47° F. Lower temperatures lengthen this period and higher ones shorten it. The newly-hatched 
larvae are about 4 millimeters in length. When the cod first hatch they float about helplessly on 
their backs. An upright position is acquired in a few days, however. The dorsal and anal fin 
