Caspian Tern
Hydroprogne caspia
It is the world's largest tern with a length of 48–60 cm (19–24 in), a wingspan of 127–145 cm (50–57 in) and a weight of 530–782 g (18.7–27.6 oz). Adult birds have black legs, and a long thick red-orange bill with a small black tip. They have a white head with a black cap and white neck, belly, and tail. The upper wings and back are pale grey; the underwings are pale with dark primary feathers. In-flight, the tail is less forked than other terns, and wingtips are black on the underside.
ID text from Wikipedia, CC BY-SA 4.0
Common Gull
Larus canus
Adult common gulls are 40–46 cm (16–18 in) long and a wingspan of 100–115 cm (39–45 in), noticeably smaller than the herring gull and slightly smaller than the ring-billed gull. It is further distinguished from the ring-billed gull by its shorter, more tapered bill, which is a more greenish shade of yellow and is unmarked during the breeding season. The body is grey above and white below. The legs are yellow in breeding season, becoming duller in the winter.
ID text from Wikipedia, CC BY-SA 4.0
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