The status of Black Oystercatchers Haematopus bachmani on Middleton Island, Alaska, in 2016

Since the first pair of Black Oystercatchers Haematopus bachmani was recorded breeding on Middleton Island, Alaska, in 1976, the island has become one of the species’ key nesting areas. I conducted a survey of the whole island in July 2016 and found a total of 860 individuals, comprising 536 territorial birds (268 pairs) and 324 birds in non-breeding flocks. This is the first count to have exceeded 800 and shows that the island now supports about 8% of the most recent estimate of the global population of the species. The most recent increase can mostly be attributed to more non-breeders, not more breeding pairs. Future work should focus on monitoring the productivity of the breeding population. Conservation concerns include disturbance by people using all-terrain vehicles and depredation of eggs and young by Common Ravens Corvus corax and Glaucous-winged Gulls Larus glaucescens.