504 BULLETIN OF THE BUREAU OF FISHERIES 



This flatfish is catholic in its choice of bottoms. Perhaps most are caught on 

 mud, especially when broken by patches of eelgrass, but it is common enough on 

 sand and clay, and even on pebbly and gravelly ground. On soft bottom it usually 

 lies buried, all but its eyes, working itself down into the mud almost instantly when 

 it settles from swimming. Flounders that live on the flats usually lie motionless 

 over the low tide to become more active on the flood when they scatter in search 

 of food. 



Winter flounders keep near the bottom. We have never heard of them com- 

 ing up to the surface as the summer flounder so often does (p. 493), but though 

 they spend most of their time lying motionless they can dash for a few yards with 

 surprising rapidity, to snap up any luckless shrimp or other victim that comes 

 within reach, or to snatch a bait, as any one may see who will take the trouble to 

 watch them on the flats on a calm day. It is in this manner and not by rooting 

 in the sand that they usually feed. 



Food. — According to Sullivan 78 diatoms are the first food taken after the 

 yolk of the larval flounder is absorbed. A little later they begin preying on the 

 smaller Crustacea, and Sullivan invariably found isopods in the stomachs of fry 

 just past their metamorphosis. A series of young flounders 1 to 43-^ inches long 

 from Casco Bay were found by Welsh to have fed as follows, mentioning the 

 major items only: Crustaceans, chiefly isopods with lesser amounts of copepods, 

 amphipods, crabs, and shrimps, 36 per cent; worms, 39 per cent; mollusks, only 

 2 per cent; various unidentifiable material, 22 per cent. Linton 77 who examined 

 about 398 young flounders of various sizes at Woods Hole, likewise found them 

 feeding chiefly on amphipods and other small Crustacea, together with annelid 

 worms, and his tables of stomach contents show an increase in ratio of mollusks to 

 Crustacea as the fish grow. The adult winter flounder, like the dab (p. 498), is 

 constrained by its small mouth to a diet of the smaller invertebrates and fish fry. 

 Sometimes they are full of shrimps, amphipods, small crabs, or other crustaceans; 

 sometimes of ascidians, bivalve or univalve mollusks (Linton says it seems that 

 they often bite off clam siphons which protrude from the sand) , bloodworms (Nereis) , 

 or other annelids. They also eat squid, holothurians, hydroids, and sometimes bits 

 of seaweed, and occasionally they capture small fish. Examination of the stomachs 

 of adults taken at Woods Hole in February, 1921, by C. M. Breder 78 showed that 

 they cease feeding when about to spawn. 



In spite of its small mouth the winter flounder bites clams very readily pro- 

 vided that bait and hook are not too large, and great numbers are caught thus in 

 harbors all along the coast. 



Rate of growth. — Judging from a large series from Casco Bay measured by 

 Welsh, the fry of the previous winter grow to an average length of 13^ to 334 inches 

 by August with an occasional specimen as long as 4 inches, and to about 234 to "& X A 

 inches by September, while in January and February, when 1 year old, the winter 

 flounders are 4 to 6 inches long off southern New England, which probably applies 



'• Transactions, American Fisheries Society, Vol. XLIV, 1914-15, No. 1, p. 135. 



" Appendix IV, Report, United States Commissioner ol Fisheries, 1921 (1922), pp. 3-14 



; » Bulletin, United States Bureau of Fisheries, Vol. XXXVIII, 1921-22 (1923), p. 311. 



