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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



fathoms, although one has been taken as deep 

 as 105 fathoms. 9 



The geographic and vertical ranges of the sea 

 raven suggest that the upper limit to its preferred 

 temperature is about 58°-60°. At the other 

 extreme their wide dispersal over the Magdalen 

 Shallows in the southern side of the Gulf of St. 

 Lawrence shows that they can winter in tempera- 

 ture close to the freezing point of salt water, 

 unless they descend then into considerably deeper 

 water, a possible shift in depth on their part of 

 which there is no direct evidence. 



Presumably the sea raven breeds throughout its 

 geographic range. Off southern New England the 

 eggs are deposited from early October (earliest 

 date, October 2) on until late December; probably 

 in autumn and early winter in the more northern 

 part of its range as well. 10 Warfel and Merriman, 

 who made a special study of the breeding of the 

 sea raven, have made the very interesting dis- 

 covery that it deposits its eggs chiefly at the bases 

 of the finger-like branches of the finger sponge 

 (Chalina) ; less often on the smaller sponge Hali- 

 chondria, where they stick together in clusters and 

 to the sponge. Since the eggs average only about 

 242 per cluster (minimum 141, maximum 478, 

 among many clusters counted), whereas adult 

 females contain something like 15,000 maturing 

 eggs on the average, and occasionally as many as 

 40,000, it appears that a female does not lay all 

 her eggs at one time, but deposits many clusters 

 during each spawning season. 



The eggs are large, averaging 3.9 to 4 mm. in 

 diameter, with tough egg membrane, yellow when 

 first spawned, but soon changing to an amber hue; 

 so heavy that they sink; and very sticky and re- 

 sistant to injury. 11 Eggs brought in to the labora- 

 tory by Warfel and Merriman hatched a few at a 

 time, and some of those of a cluster collected on 

 January 23 and left thereafter in a bottle fastened 

 to a buoy (i. e., in the normal winter temperature 

 of Long Island Sound) did not hatch until 

 March 12. 



• A specimen about 14 inches (360 mm.) long was trawled by the U. S. 

 Fish and Wildlife vessel Delaware August 24, 1951, in 105 fathoms, latitude 

 42°06' N., longitude 67°50' W. 



i° Warfel and Merriman (Copeia, 1944, p. 202) probably were correct in 

 their suggestion that a 20-inch female, containing ova of 2 sizes, caught by 

 us off Boothbay, Maine, in April, was simply one that had failed to spawn 

 at the proper time during the preceding winter. 



» Described by Bean (Bull. 60, New York State Mus., Zool. 9, 1903, p. 647). 

 The buoyant eggs referred to this species by Agassiz and Whitman (Mem. 

 Mus. Comp. Zool., vol. 14, No. 1, 1885, p. 10) belonged to some other fish. 



The sizes of the few young sea ravens that have 

 been taken in the Gulf of Maine suggest that 

 they reach a length of 2 to 4 inches by the middle 

 of their first summer, when 6 to 8 months old, 

 and about 6 inches by the following April, at 

 an age of 1% years. Their subsequent rate of 

 growth has not been followed. 



General range. — Atlantic Coast of North America, 

 southward to Chesapeake Bay; north to Anticosti 

 in the northern side of the Gulf of St. Lawrence, 

 to the Strait of Belle Isle on the Newfoundland 

 side 12 and to the Grand Banks. 13 



Occurrence in the Gulf of Maine. — Sea ravens 

 are to be caught all around the coastal belt of the 

 Gulf, from a fathom or two down to about 50 

 fathoms, including the passages among the islands 

 that fringe the coasts of Maine and of Nova 

 Scotia, as well as the larger estuaries such as 

 St. Mary, Passamaquoddy, Machias, Penobscot 

 (it runs up the latter to the head at Bucksport), 

 and Casco Bays; also in the deeper harbors, for 

 example Boston, Salem, Eastport, and St. Johns. 

 Fishermen also report them on Cashes Ledge, 

 while the otter trawlers and long liners pick them 

 up in small numbers over the shoaler parts of 

 Georges Bank; likewise on Browns. But they are 

 not known to occur on the soft mud bottoms of the 

 deep troughs and basin of the Gulf. 



Presumably the sea raven breeds in the Gulf 

 wherever it occurs, young fry having been taken 

 from the Bay of Fundy to Cape Cod. 



Off the southern shores of New England sea 

 ravens work inshore in autumn and out again 

 into slightly deeper water in spring, but no season- 

 al movement of this sort (which means merely 

 that shoal water is too warm for their comfort in 

 summer) has been reported for them in the cooler 

 waters of the Gulf of Maine. 



Although they are distributed so generally 

 in the Gulf, sea ravens are not so numerous as the 

 shorthorn sculpins and longhorn sculpins; this 

 is as true in the Bay of Fundy as it is in Mas- 

 sachusetts Bay, where one expects to catch a few 

 ravens around any of the fishing ledges, but 

 where it would be unusual for one person to land 

 any considerable number in a day. Similarly, the 

 schedules of the catches made bv certain otter 



■» Jeflers (Contrib. Canadian Biol. N. Ser., vol. 7, No. 16, (Ser. A, No. 

 13,) 1932, p. 208). 



" Bean (Proc. U. S. Nat. Mus., vol. 3, 1881, p. 86) lists a specimen from the 

 Grand Banks. 



