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RORQUAL
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RORQUAL , a See also:whale of a See also:long and elongated shape, with a small back-fin and a number of See also:longitudinal pleatings or folds on the See also:throat (see See also:CETACEA). The name rorqual refers to these folds, while the alternative See also:title of finner, or fin-whale, marks an important difference between these whales (for there are several See also:species) and right-whales. The furrows on the throat are numerous and See also:close-set, the flipper is comparatively small, and the dorsal fin distinct. The See also:head is relatively small, See also:flat and pointed in front, the See also:whalebone See also:short and coarse, the See also:body long and slender, and the tail much compressed before it expands into the "flukes." Rorquals are the most abundant and widely distributed of all whales, being found in all seas, except the extreme See also:Arctic and See also:Antarctic regions. There are four distinct species of this genus in See also:British seas. Firstly, See also:Sibbald's rorqual, or See also:blue whale (Balaenoptera sibbaldi), the largest of all animals, attaining a length of 8o or even sometimes 85 ft. Its See also:colour is dark bluish See also:grey, with small whitish spots on the See also:breast; the whalebone is See also:black; the flippers are larger proportionally than in other rorquals, measuring one-seventh of the See also:total length of the body; and the dorsal fin is small and placed far back. This whale has usually 64 vertebrae, of which z6 See also:bear ribs. Like the others, this species seems to pass thewinter in the open seas, and approaches the See also:coast of See also:Norway at the end of See also:April or beginning of May. At this See also:time its See also:sole See also:food is a small crustacean (Euphausia inermis), which swarms in the fjords. Secondly, we have the See also:common rorqual (B. musculus, or B. physalus) with a length of from 65 ft. to 70 ft., and of a greyish See also:slate-colour above and See also: This is the commonest of all the large whales on the British coasts; scarcely a See also:winter passing without the body of one being washed ashore, usually after stormy See also:weather, and frequently on the See also:south coast, as this species has a more See also:southern range than the last, and enters the Mediterranean. It feeds largely on See also:fish, and is frequently Common Rorqual (Balaenoptera musculus). seen feasting among shoals of See also:herrings. Thirdly comes Rudolphi's rorqual (B. borealis), a smaller species, scarcely attaining a length of 50 ft. It is bluish black above, with oblong See also:light-coloured spots, whilst the under-parts are more or less white; the whole of the tail and both sides of the flippers are black; the whalebone is black, and the bristly ends See also:fine, See also:curling and white; the flippers are very small, measuring one-See also:eleventh of the total length of the body. There are 56 vertebrae, with 14 pairs of ribs. This species, according to Dr. C. Collett, feeds chiefly on See also:minute crustaceans, mainly Calanus finmarchicus and Euphausia inermis, and not on fish. Down to the last See also:quarter of the 19th See also:century it was considered the rarest of the whales of See also:European seas, and was only known from a few individuals stranded on the coasts of See also:northern See also:Europe at long intervals. The most southern point at which it has been met with is See also:Biarritz. Since the See also:establishment of the whaling station near the See also:North Cape it has been shown to be a See also:regular summer visitor. Lastly, the lesser rorqual, B. rosirala, the See also:sharp-nosed finner of See also:American whalers, is the smallest species found in the northern seas, rarely exceeding 30 ft. in length. Its colour is greyish black above, whilst the under-See also:side is white, including the whole of the See also:lower side of the tail; the inner side of the flippers is also white, and there is a broad white See also:band across the See also:outer side, which is a very characteristic See also:mark of the species; the whalebone is yellowish white. The dorsal fin in this and the preceding species is comparatively high, and placed far forwards on the body. This whale has usually 48 vertebrae, of which 11 bear ribs. It is common in summer in the fjords of Norway, and is often seen around the British Isles. It has been taken, though rarely, in the Mediterranean, and ranges as far north as See also:Davis Strait. Rorquals are met with in almost all seas, and nearly all the individuals carefully examined, whether from the North Pacific, the Australian seas or the See also:Indian Ocean, come very near in structure to one or the other of the See also:Atlantic forms described above, so much so that some zoologists believe that there are but four species, with an almost See also:cosmopolitan range. Other naturalists, on the contrary, have described and named almost every individual specimen captured as belonging to a different species. See WHALE and HUMP-BACK WHALE. (R. Additional information and CommentsThere are no comments yet for this article.
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