Recognisable through its specialised feeding behaviour, Saunder’s gull flies over coastal mudflats 10 metres above the ground, searching for prey. On sighting a prey item it dives vertically, landing and pecking at the prey before it has time to enter its burrow. With this technique Saunder’s gull captures crabs and mudskippers, but during the winter it will also feed on fish and worms. It is known to steal prey from other bird species. The webbing on the feet on Saunder’s gull does not cover the whole foot, making this coastal species a poor swimmer. It appears to avoid water altogether, moving up the shore as the tide rises (4).
Saunder’s gull arrives at the breeding grounds in March and breeds from early April to early May. Monogamous pairs build a simple nest and defend their territory, attacking intruders. A clutch of two or three eggs is laid in May and is incubated for 21 to 23 days. Fledglings and adults leave the breeding grounds in October (4).