The Socorro Dove (Zenaida graysoni) is a dove that is extinct in the wild. It was endemic to Socorro Island in the Revillagigedo Islands; the last sighting in its natural habitat was in 1972. There are not more than some 200 and probably fewer than 100 purebred birds in captivity. A reintroduction program is in the early stages of preparation.It is a close relative of the Mourning and Eared Doves, particularly the former and was at one time considered its subspecies. In captivity, it hybridizes vigorously with the former and almost all privately-owned birds as well as several of the captive breeding programme that lacked a pedigree are known or strongly suspected to be such hybrids; they are for the time being excluded from the reintroduction programme as there is evidence of unique adaptations in the Socorro species.The Socorro Dove is a medium-sized, principally terrestrial dove with long legs for a Zenaida dove. It is 26.5-34 cm long and weighs 190 g on average.In overall color pattern, it agrees with its relatives. It may be considered a stronger-colored insular representative of the Mourning Dove; the male is deep cinnamon on head and underparts, with an ear streak like in the two closest relatives. Its nape is blue-grey and the neck has an iridescent pink patch, most prominent after moult. The upperparts are rufous brown. Female and juvenile coloration is slightly duller. The most conspicuous differences to the Mourning Dove - darker coloration and more well-developed feet - were useful amid the dark lava rock and the shady forests of its island home, where native mammalian predators were absent but a constant threat from Red-tailed Hawks and maybe Great Frigatebirds was present. The advertising call begins with a disyllabic coo, followed by three single calls, and ends with another disyllabic coo: "Coo-oo, OO, OO, OO, Coo-oo". Each of these 5 elements takes a little less than one second.
