Guadalupe Storm-petrel (Oceanodroma macrodactyla)
Justification Predation by feral cats may have extirpated this species from the one island where it was known to breed. If it is still extant, the population is likely to be tiny and it consequently qualifies as Critical. Thorough and unsuccessful surveys will result in the species being listed as Extinct.Identification 23 cm. Largish, fork-tailed storm-petrel with white rump. Generally blackish-brown above with paler grey wing-bar. White uppertail patch with darker median stripe extending to lateral coverts. Moderately forked tail. Underparts slightly paler than upperparts. Similar spp. Intermediate Leach's Storm-petrel O. leucorhoa has darker underwing, but very difficult to separate.
Range & Population Oceanodroma macrodactyla may persist on Guadalupe, Mexico, 280 km west of Baja California. It was abundant in 1906, but the last record of a breeding bird was in 1912. Searches in 1922, 1925 and the early 1970s failed to find the species. However, there has been no thorough survey in the appropriate season since 1906. Relatively recent reports of storm-petrels calling at night and the apparent persistence of breeding Leach's Storm-petrel O. leucorhoa on the island raises some hope that it may survive. Its non-breeding range is unknown
Ecology It nested in burrows in soft soil under pines Pinus radiata var. binata and cypress Cupressus guadalupensis groves. Eggs are known to have been laid between early March and late June.
Threats The main cause of its demise is thought to be heavy predation by feral cats, compounded by goats destroying and degrading nesting habitat.
