FISHES OP THE GULF OF MAINE 35 



pass the southern elbow of Cape Cod, it is more often seen and taken in the Gulf of 

 Maine than is any other large shark except the mackerel shark (p. 36) or perhaps 

 the thresher. There is well-established record of its presence at Monomoy, North 

 Truro, Provincetown (where it has been caught often enough to have received the 

 local name of dogfish shark, appropriate because of its small size), Cohasset in 

 Massachusetts Bay (where the senior author caught one about 4 feet long years 

 ago), in Boston Bay, at Lynn, at the mouth of Casco Bay, and even near St. Andrews 

 in the Bay of Fundy — its most northerly outpost — where a stray specimen was taken 

 in a weir in 1913. Probably, were all the sand sharks that entangle themselves in 

 nets reported, we would find that it ranges northward as far as Casco Bay every 

 summer and in much greater numbers than the actual published record would 

 suggest. Any "shovelnose" reported from northern New England would probably 

 belong to this species; and no doubt it is represented among the "ground sharks" 

 taken by fishermen on Georges Bank, though definite information is lacking on this 

 point. 



Habits and food. — This shark, in the warm months at least, swims chiefly near 

 the bottom in shoal water, often coming right up on the beaches almost to tide mark 

 and even entering the mouths of rivers. Over certain bars, however, it often comes 

 to the surface, where it may be seen moving slowly to and fro with its dorsal and tail 

 fins projecting above the surface. It captures great numbers of small fish, which are 

 its chief diet, particularly menhaden, cunners, mackerel, skates, silver hake, flounders, 

 alewives, butterfish, and — south of Cape Cod — scup, weakfish, and bonito. It also 

 eats lobsters, crabs, and squid. Although comparatively sluggish in habit, as sharks 

 go, sand sharks have been seen surrounding and devouring schools of bluefish, and 

 have even been known to attack nets full of bluefish, which gives a measure of their 

 voracity. There is no record or even well-grounded rumor that this shark ever 

 attacks human beings. Indeed, it is looked upon merely as a harmless nuisance 

 wherever it is common enough to be familiar. So far as the Gulf of Maine and, 

 indeed, the southern coast of New England as a whole are concerned, the sand 

 shark occurs only as a summer visitor, moving away either southward or into deep 

 waters during the cold season. 



Breeding habits. — Nothing is definitely known of its breeding habits. Females 

 with unripe eggs have been taken at Woods Hole in July. 



Commercial value. — This shark has no commercial value except the negative 

 one of damaging nets, but so readily does it bite a hook that it is of some importance 

 as an object of sport, though hardly so in the Gulf of Maine, where it is never 

 plentiful enough to be worth fishing for. 



THE MACKEREL SHARKS. FAMILY ISURID^I 



This group of sharks is easily recognizable by the fact that the tail is very firm 

 and lunate in outline with the lower lobe but little smaller than the upper, suggest- 

 ing a swordfish's tail, and that there is a prominent keel on either side of the 

 caudal peduncle. The dorsal fins are spineless. 



