Birds of Singapore
by the Bird Society of Singapore
Chroicocephalus ridibundus
Family: Skimmers, Noddies, Terns, and Gulls · Status: Rare migrant · Size: 35–39 cm · Conservation: Least Concern
Breeds inland across Europe, Asia, and small parts of Greenland and Iceland. Winters to coastal regions in northern Africa, the Middle East, the Indian subcontinent, China, Korea, Japan, Southeast Asia and the eastern coast of North America.
Non-breeding adult is mostly white all over the head and body, with prominent black ear spot and indistinct black markings around and above the eye. On the upperside, back, mantle, and inner flight feathers are grey. Eyes are dark and the bill is red with a black tip. In flight, outer primaries appear largely white with black only on the tips, appearing as a prominent flash of white on the leading edge. When visible, feet are webbed and dark red. Breeding adult has dark brown hood with a white eyering that is broken at the front and thicker towards the back. First-winter bird resembles non-breeding adult but has duller bill and legs, flight feathers are black at the tips forming a broad dark trailing edge, uppperwing coverts are dark brown with broad white edges giving a scaly appearance, and shows a black band at the tip of the tail. Very similar Brown-headed Gull is larger and bulkier, has pale eyes (not always visible at distance), and shows a solid black wingtip in flight, lacking the prominent white leading edge, although good views of the wingtips are needed.
During non-breeding season, found at coastal habitats including mudflats, also appears at reservoirs. In Singapore, recorded at Mandai Mudflat, Straits of Johor, Seletar Dam, and Chek Jawa.
Adaptable and has a varied diet, feeding on insects, earthworms and marine worms, marine invertebrates, fish, grains and berries, and shellfish. Sometimes found in large flocks following fishing boats for food.