70 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



northern Nova Scotia to Virginia, in coastal waters 

 and on the shoaler of the offshore banks. 



Occurrence in the Gulf of Maine. — This, the 

 smallest of our skates, is the commonest and the 

 most familiar from its habit of coming up into 

 very shoal water in summer and of stranding on 

 the beaches, where dried skate carcasses are often 

 to be seen. It occurs all along the coast in the 

 southern side of the Gulf of St. Lawrence and 

 along outer Nova Scotia; is very abundant both on 

 the New Brunswick and on the Nova Scotia sides 

 of the Bay of Fundy, and is to be caught every- 

 where and anywhere along the coasts of Maine 

 and of Massachusetts ; far more commonly, indeed, 

 than one might suspect from the few definite 

 records that have found their way into scientific 

 literature. 



An average catch of about 88 per haul (about 

 60 percent of all the skates taken) in 42 trawl 

 hauls by the Eugene H, in late June 1951, fishing 

 eastward from Nantucket Lightship suggests that 

 this is the most plentiful skate on the south- 

 western part of Georges Bank and on the Nan- 

 tucket grounds. But it seems to be far less 

 numerous on the northeastern part of the Bank, 

 if it is present there at all; at least we failed to 

 find a single one, among 495 skates of other kinds 

 caught there in 37 hauls by the otter trawler 

 Kingfisher in September 1929. And we have 

 never found it (nor has it been reported) in the 

 deeper basins and troughs of our Gulf, probably 

 because it is restricted in general to depths less 

 than 40 to 50 fathoms (p. 69). 



In our Gulf many of the little skates appear to 

 carry out an irregular migration into shoal water 

 in April and May, where they remain throughout 

 the summer, autumn, and early winter, to retire 

 again to somewhat deeper, hence, warmer water 

 in December or January. Its migration schedule 

 appears to be more complex in Long Island Sound 

 waters where summer temperatures are higher; 

 i. e., inshore in spring, offshore in mid- or late 

 summer, inshore again in late autumn and offshore 

 again in midwinter. 74 Doubtless little skates 

 breed throughout the shoaler parts of the Gulf, 

 and on the offshore banks. 



They are of no commercial importance in our 

 Gulf except as they form a part of the landings of 

 trash fish. 



" Information from Dr. Daniel Merriman, Dr. Y. H. Olsen, the Misses 

 S. B. Wheatland and L. H. Calhoun of the Bingham Oceanographic Lab- 

 oratory. 



Smooth-tailed or prickly skate Raja senta 

 Garman 1885 



Bigelow and Schroeder, 1953, p. 264. 

 Garman, 1913, pi. 25, fig. 1. 



Description. — By the time this skate has grown 

 to one-fourth its adult size it is made recognizable 

 by the fact that the middorsal line of thorns runs 

 back only to about the middle of the tail, where the 

 thorns so dwindle in size that they are not dis- 

 tinguishable from the tiny prickles with which the 

 tail is clothed, generally. Newly hatched speci- 

 mens in which this character is not yet established 

 are separable from all other Gulf of Maine skates 

 by the color pattern of the tail, which has two pale 

 crossbars, each outlined in front and behind by a 

 dark band or blotch. 



There is a single row of 16 or more medium- 

 sized to large thorns along the midline of the back, 

 spaced irregularly, and usually about 20 to 30 

 along the anterior one-half or so of the tail ; about 

 10 to 13 around the inner ridge of each eye; and 

 3 to 5 on each shoulder. Immature specimens of 

 both sexes are also closely and uniformly rough- 

 ened with small prickles over the disc as a whole, 

 on the pelvics and on the upper side of the tail. 

 But irregular bare areas develop on the shoulders 

 and around the outer parts of the pelvics of females 

 as they approach maturity while mature males 

 lose the prickles from the central part of the disc 

 as a whole, but develop a few thorns on the mid- 

 ridge of the snout besides larger thorns over a 

 roughly triangular area on either side of the head 

 abreast of the eyes and farther forward. They 

 also develop two rows of the usual curved sexual 

 spines on either side on the pectorals, about 13 

 to 14 per row. The lower surface of the disc is 

 smooth, except that a few prickles develop, with 

 growth, along the margins near the snout 



The lower surface of the tail as a whole is 

 prickly on females and on immature males, but 

 tends to become smooth on males by the time 

 they mature sexually. 



The anterior angle of the snout is a little more 

 obtuse than a right angle (about 110°); the tip of 

 the snout is sharper than in either the big skate, 

 the little skate, or the thorny skate. There are 38 

 to 40 series of teeth in the upper jaw, 36 to 38 

 series in the lower jaw; those of females are low, 

 with only faintly indicated points, but those of 

 mature males are longer, sharper, recurved, and 



