A RING-BILLED GULL ON THE GALAPAGOS ISLANDS

Abstract

On 30 June 1983, on South Plaza Island, Galápagos Archipelago, we observed a gull obviously different from the resident Swallow-tailed (Creagrus furcatus) and Lava (Larus fuliginosus) gulls of the islands. We initially found the gull in one of the abundant tide pools along the island’s rocky shore. From there, it flew a short distance to a sea lion carcass, where it supplanted a Lava Gull and fed on the maggots covering the rotting carcass. The gull then flew a few hundred meters to a pool where several members of our party took close-up photographs (e.g., Figure 1) that show the bird to have been a Ring-billed Gull (Larus delawarensis) in adult plumage.