Blokpoel H., Boersma DC., Hughes R.A. & Tessier G.D. (1992) Foraging by larids on Sand Crabs Emerita analoga along the coast of southern Peru. ARDEA 80 (1): 99-104

Observations were made of foraging by three larids on the sand crab Emerita analoga in the wave-washed zone of a sandy beach along the Pacific coast of southern Peru. Resident Gray Gulls Larus modestus foraged by probing the wet sand with their bill as well as by digging out prey that they had apparently seen. Wintering Franklin's Gulls L. pipixcan foraged on foot and on the wing and caught crabs by running towards them. Franklin's Gulls did not probe. Wintering Common Terns Sterna hirundo foraged only on the wing and caught crabs by quickly diving down to the wet sand. Sand crabs were of major importance in the diet of Gray Gulls and Common Terns but not of Franklin's Gulls.