Fishes of the Western North Atlantic 385 



Like other Sting Rays, T>. say is a bottom feeder. Specimens taken in estuarine 

 waters near Beaufort, North Carolina, contained chiefly annelid worms and small 

 bivalves, including many detached siphons of the latter, probably bitten off while pro- 

 truding from the sand; they had also eaten lesser amounts of gastropods, amphipods, 

 shrimps, crabs and fish. Otherwise we know only that in French Guiana it eats small 

 mollusks, as well as mud, no doubt for the animals contained therein. 



Doubtless this species is a year-round resident throughout the tropical-subtropical 

 part of its habitat northward to middle Florida. But it visits the more northerly sector 

 of its range along the Atlantic Coast of the United States only as a warm-season 

 migrant, appearing on the North Carolina Coast early in May and remaining there all 

 summer. At least some specimens reach the mouth of Chesapeake Bay and the adjacent 

 coast nearly as early as they reach North Carolina, for they have been reported on May 

 15139 from Smith's Island, Virginia. June 10 is the earliest recorded capture from any 

 part of the coast farther north."" Apparently such of the stock as visits Delaware Bay 

 and the coast of New Jersey have withdrawn again by early autumn, the few dated 

 records published thus far being for June, July, and August. However, they are plenti- 

 ful during late September and early October in the lower part of Chesapeake Bay. 

 Available information suggests that it is not until the latter part of October that they 

 move southward from the North Carolina Coast, where some linger until November. 

 It is also likely (to judge from winter temperatures) that T). say withdraws from the 

 Louisiana and Texas shores at some time during early winter, but definite information 

 is lacking. 



The dates of arrival of T). say in the vicinity of Cape Lookout, North Carolina, 

 and in the general vicinity of Chesapeake Bay (p. 385) suggest that its northward disper- 

 sal in spring keeps pace with the northerly advance of the isotherm of about 19-20° C 

 (about 66—68° F). The time of its disappearance from the northern part of its range 

 in autumn suggests that it tends to withdraw as soon as the water cools to approx- 

 imately this same temperature. And its presence in shallow water within the tropics, 

 as in French Guiana, shows that it is at home in the highest temperatures normally 

 occurring anywhere along the western shores of the Atlantic or of the Caribbean. 



D. say differs from T>. sabina in that it has never been reported from fresh water. 

 But it does occur over a wide range of salinities, from brackish situations as in the 

 Indian River, Florida, to salinities of 32—33 "/oo along the open coasts of the Middle 

 Atlantic United States, and among the West Indies it appears in water that is consider- 

 ably more saline than that. 



Numerical Abundance. For Florida and North Carolina waters D. say has been 

 termed abundant, and it has been referred to as common northward even to Chesapeake 

 Bay. But the only precise information as to its actual numbers anywhere is that we 

 have seen as many as 40 individuals taken in one lift of a pound net in Lynnhaven 

 Roads, Virginia. 1" 



139. Fowler, Occ. Pap. Mus. Zool. Univ. Mich., 56, 1918: 16. 140. Sea Island City, New Jersey. 



141. Hildebrand and Schroeder, Bull. U. S. Bur. Fish., 43, 1928: 66. 



