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The heads of species black-headed in 

 summer turn white in winter, while 

 the white-headed Gulls of the summer 

 usually have dark streaked heads 

 during the winter. 



Five species of Gulls are commonly 

 found along the China coast, at or near 

 the mouth of the Yangtse Eiver. 



YELLOW-LEGGED HEBEING 

 GULL. 



LARUS CACHINNANS (pALL). 



Description. — Length 23 inches. 

 Bill yellow with a red spot on the 

 lower mandible. Feet and legs yellow. 

 Skin around the eye vermilion. 



Head white in summer, streaked 

 with brown in winter. Neck and 

 under parts white. Mantle light blue 

 grey. The light pattern on the inner 

 webs of the primaries is very distinct 

 and wedge-shaped. Tail white. Wing 

 primaries black. 



Young birds are mottled grey and 

 brown. The bill is horn color and the 

 legs dark. The tail has a dark sub- 

 terminal band. Full adult plumage is 

 not assumed until the third year. 



This Gull resembles very closely 

 the European Herring Gull, (Larus 

 argentatus), differing only in the color 

 of the bill and feet, and that its mantle 

 is slightly darker. 



Distribution. — Eastern Siberia and 

 the coasts of China and Japan, west- 

 ward across Asia and down to the 

 Mediterranean Sea. In China, it is 

 occasionally found at some distance 

 from the sea. 



It winters in the Yangtse Valley and 

 nests in the North. 



