30 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



winter in deeper water where the temperature 

 does not fall so low. 



Next to its vast bulk and its curiously sluggish 

 habit, the most interesting peculiarity of the bask- 

 ing shark is its diet, for it subsists wholly on tiny 

 pelagic animals, which it sifts out of the water by 

 means of its greatly developed gill rakers, exactly 

 as plankton-feeders among fishes such as men- 

 haden do, and whalebone whales with their baleen 

 sieves. In several cases their stomachs have been 

 found packed with minute Crustacea; this was true 

 of the only western Atlantic specimen of which 

 the stomach contents have been examined. And 

 while digestion is so rapid that the food swallowed 

 is soon reduced to a soupy mass, this usually is 

 reddish, suggesting a crustacean origin. 



All that is known of the breeding of the basking 

 shark is that the structure of the internal sex or- 

 gans of the female accords with the nourishment 

 of the embryo within the maternal oviduct, 

 that the ovary of a female, with empty oviduct 

 contained something like 6 million immature ova 

 instead of the few that are usual in sharks that 

 bear "living" young, and that an embryo about a 

 foot long was said, long ago, to have been taken 

 from its mother. 64 



Basking sharks reported as "sea serpents" or as 

 other "monsters" . — The remains of basking sharks 

 have been reported as "sea serpents" on several 

 occasions; nor is this astonishing. "As the carcass 

 of the shark rots on the shore, or is buffeted 

 against the rocks, the whole of the gristly skeleton 

 of the jaws and gill arches ... as well as the 

 pectoral and pelvic fins, is soon washed away," 65 

 leaving only the cranium and the long backbone, 

 with larger or smaller amounts of muscle, so frayed 

 out as to suggest a hairy or bristly mane. As 

 a recent instance from the Gulf of Maine, we may 

 cite the newspaper and radio publicity, that was 

 given, as a supposed sea serpent, to a basking 

 shark skeleton, about 25 feet long, that beached 

 near Provincetown on the outer shore of Cape 

 Cod, in January 1937, that we examined. 66 



A more spectacular instance of the fanciful in- 

 terpretation that is likely to be placed on any 

 large stranded carcass that has decayed partially, 

 was the famous "Animal of Stronsa," that came 



« See Matthews, Philos. Trans. Eoy. Soc. London, Ser. B, No. 612, vol. 

 234, 1960, pp. 347—366 for detailed account. 



" Norman and Fraser. Giant Fishes, Whales and Dolphins, 1937, p. 21. 



* For account and photograph, see Schroeder, New England Naturalist, 

 No. 2, 1939, p. 1. 



ashore on the island of that name in the Orkneys, 

 in September 1808. It was pictured by an eye- 

 witness as having three pairs of limbs, but the 

 published illustration of its cranium, vertebrae, 

 and pelvic skeleton 6: show that it was only the 

 remains of some very large shark, probably a 

 basking shark. It has also been suggested repeat- 

 edly that some of the stories of sea monsters of 

 one sort or another may have been based on the 

 dorsal and caudal fins of two or more basking 

 sharks, swimming one behind another as they 

 often do (we dare not touch further on the contro- 

 versial subject of the "sea serpent"). 



General range. — This enormous fish, formerly 

 thought to be an Arctic species, straying south- 

 ward, is now known to be an inhabitant of the 

 temperate-boreal zone of the North Atlantic. 68 

 It is represented in the corresponding thermal 

 belts of the South Atlantic and of the North 

 and South Pacific by a similar great shark (or 

 sharks), whose exact relationship to the basking 

 shark of the North Atlantic is still an open question. 



The northern boundary of the normal range 

 of the basking shark of the North Atlantic appears 

 to follow the line of transition from waters of 

 predominately Atlantic influence to those of 

 Arctic origin. This, roughly, runs from the outer 

 coast of Nova Scotia (1 record), and from southern 

 Newfoundland (4 positive records) to western and 

 southern Iceland, to the Orkney and Faroe Islands, 

 and skirts the Norwegian coast to the North 

 Cape, while basking sharks stray now and then 

 to the Murman coast. To the southward, in the 

 North Atlantic, they range as far as the Mediter- 

 ranean and Morocco in the east, to North Carolina 

 in the west. 



Occurrence in the Gulf of Maine. — Before the 

 coming of the white man this great shark seems 

 to have been a regular inhabitant of the southern 

 part of the Gulf of Maine. And tradition has 

 it that large numbers were taken in Massachusetts 

 waters, especially off the tip of Cape Cod, during 

 the first half of the eighteenth century, for their 

 liver oil which was then in demand for illuminating 

 purposes. However, the local stock seems soon 

 to have gone the same way as the local stock of 

 the North Atlantic right whale; that is, into the 

 try pot. And basking sharks seem never to have 



i Barclay, Mem. Wernerlan Soc, Edinburgh, vol. 1, 1811, p. 418. 



• ! It has long been realized that old tales of a tremendous whale-eating 

 shark, on which Fabricius based his statement that the basking shark occurs 

 In Greenland waters, were fiction. 



