STRANDED ON THE BRITISH COASTS. 



153 



(5) Bottle-nosed Whale {Hyperoodon rostratus Mull.). 



Fourteen records, mostly from the Northern coast of Scotland, 

 along the entire Eastern coast of Scotland and England, and in 

 the South of England as far west as Somerset. 



The Bottle-nosed Whale has long been hunted in Northern 

 seas (cf. Collett, 1906), and its movements are better known 

 than those of many other species. According to Hjort (1912, 

 p. 649, chart on p. 650) it is present in considerable numbers in 

 the Norwegian Sea during April-July; extending as far North as 

 Lat. 76° in June. In September, when it is migrating South, the 

 Faroe Islanders get their last Bottle-noses. The localities where 

 it is principally found are on the Western side of the Gulf 

 Stream water, in the transition-belt between the Arctic and 

 Atlantic currents. The individuals of this species are said to 

 follow the 800-fathom line during their migration. 



It has been pointed out by several authorities (cf. Turner, 

 1886, p. 45) that Bottle-nosed Whales are most commonly 

 stranded on the British coasts in the autumn, when on their 

 Southward migration ; the individuals recorded being either 

 young specimens of either sex or adult females, often accompanied 

 by a calf. The occurrence of the species, as shown by the British 

 Museum records, is in general agreement with this statement, 

 except that the sex of the majority of the specimens is not 

 definitely known and there are no records of females with calves. 

 There is one record for each of the months July (1917) and 

 August (1916), both from Scotland ; four for each of the months 

 September and October ; and one from the South of England 

 (Somerset) in November, 1914. The only others of which 

 evidence has been obtained are two in March (Northumberland, 

 1914 ; Caithness, 1915), and one near Nairn, in May, 1914. 



A remarkable alteration is known to occur in the male Bottle- 

 nosed Whale, with increasing age, both in external form and in 

 cranial characters. The changes in the skull are principally due 

 to the immense increase in the height and thickness of the 

 maxillary crests which are so characteristic a feature of % this 

 species, the adult males having formerly been described as a 

 distinct species, H. latifrons Gray. With this increase in the 

 maxillary crests is associated a corresponding change in the profile 

 of the head ; the " forehead " becoming more and more prominent 

 until in old age its anterior outline is quite vertical. The old 

 males appear to have a migration-route which is further from the 

 land than that of the adult females ; with the result that they are 

 hardly ever recorded on the British coasts (Turner, 1886, p. 45). 



According to Southwell (1883, p. 480) the young Bottle-nose is 

 black, the colour becoming lighter with age ; old specimens being 

 almost yellow, with a. greyish white ventral surface, while 

 the beak and front of the head are quite white. The oldest 

 males may become white all over (Millais, 1906, p. 298). 



This species is provided with a pair, or sometimes two pairs, of 



