Auks, Gulls, and Plovers 



419 



Plwto hy Scliola^iic Photo. Co.] 



[Payson'x Green. 



IIERRING-GULL. 



its egg on the leaf of a cocoanut-iialm— truly a wonderful site, and still more wonderful when 

 we reflect that it is chosen by one of the Gull Tribe. 



About six species of tern commonly occur in the British Islands, and some five or six 

 other species occasionally visit them. 



Skimmers. 



The Skimmers are tern-like birds, 

 with a very wide geographical distri- 

 bution, occurring in India, Africa, and 

 North and South America, and re- 

 markable for the very extraordinary 

 form of the beak. The upper jaw is 

 much shorter than the lower, and both 

 are compressed to the thinness of a 

 knife-blade. This beak is associated 

 with, and is probably an adaptation 

 to, an equally remarkable method of 

 feeding, which has been admirably 

 described by Darwin, who watched 

 them feeding in a lake near IMaldonado. So called from its h.-ibit of foiiowins the stioais of heniugs. 



" They kept their bills," he says, 



" wide open, and the lower mandible half liuried in the water. Thus skimming the surface, 

 they ploughed it in their course ; and it formed a most cm-ious spectacle to behold a flock, 



each bird leaving its narrow wake on the mirror-like surface. In their flight . . . they 

 dexterously manage with their projecting lower mandible to plough up small fish, which are 

 secured by the upper and shorter half of their scissor-like bills.'' 



The Gulls. 



Gulls are larger and 

 heavier birds than terns, with 

 longer legs, and shorter, 

 thicker beaks. Furthermore, 

 with one exception, the tail is 

 never forked. Like the terns, 

 gulls generally breed in 

 colonies, and these are often 

 of large size. Young gulls, 

 when newly hatched, are quite 

 active. Later, when their 

 feathers have grown, they are 

 found to wear a dress quite 

 different from that of the 

 parents. Sometimes the adult 

 plumage is gained at the end 

 of the first year of existence, 

 sometimes not until after the 

 third j^ear. Gulls feed on 



everything that comes in their way, from fish caught swimming at the surface of the sea to 

 worms picked up at the plough-tail. 



One of the commonest and best known of all the gulls is perhaps the species known 

 as the Black-headed Gull, which has become so common in the heart of busy London, 

 where hundreds may be seen, during the winter months, flying up and down the river, or 



Plwta by SchaOultc Pliulu. CVj.J [P'lr.^o.i's Gr 



TOUSG HEKKISG-GULLS IS THE GEEiT PHASE OF PLUMAGE. 

 In their dull grey plumage the young of all gulls are very ur]like the adults. 



