272 THE BLACK-HEADED GULL. 



against the brightness." ^ It may also be observed haunting 

 the streams immediately below Coldstream Bridge in search 

 of prey, where its sprightly and graceful motions lend addi- 

 tional beauty and interest to the lovely scenery. Mr. Lockie 

 remarks that it frequents the Leader about Earlstou. 



This species appears to be omnivorous, but its chief food 

 consists of earthworms, grubs, wire-worms, insects, crusta- 

 ceans, molluscs, and small fish. 



During the winter the head of this Gull is white, streaked 

 with grey, and there is a patch of grey before the eye and 

 behind the auricles. In March the head and upper part of 

 the neck become dark-brown, making the bird look as if it 

 had a black cap on its head ; hence several of its local names. 

 Both Yarrell and Seebohm state that the feathers of the 

 head actually change colour in spring, and do not moult. 

 Mr. Andrew Brotherston, bird-stuffer, Kelso, says : " That it 

 is the result of moulting, in some cases at least, I am 

 thoroughly satisfied. On the 15th of March 1876 I ex- 

 amined the head of an adult male, in which the change 

 was nearly completed, only a few scattered white feathers 

 were left, all of which were old and easily detached, so 

 much so that, excepting a few at the base of the bill, they 

 came off when I was skinning the bird. The black feathers, 

 on the contrary, were all young, new, and in various stages 

 of growth, some fully developed, others just appearing. I 

 examined several examples of the same species in March 

 1877, all of which showed unmistakable signs of moulting 

 on the head, and also on the rest of the body, excepting the 

 large feathers."^ 



The late Dr. Colville Brown of Berwick writes on the 

 9th of April 1879 : " For the last three years I have closely 

 watched the change of colour in the Black-headed Gull, and 

 I am now quite convinced this proceeds from moulting and 



1 Hist. Ber. Nat. Club, vol. x. p. 253. 2 mj,^ vol. viii. p. 187. 



Ji 



