Bahama oriole

Bahama oriole
Conservation status
Critically Endangered  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Icteridae
Genus:	Icterus
Species:	I. northropi
Binomial name
Icterus northropi (J. A. Allen, 1890)

The Bahama Oriole (Icterus northropi) is a species of songbird in the New World blackbird family - Icteridae. It is endemic to the Bahamas. It is listed as critically endangered by IUCN (CR). The taxon was originally classified as its own distinct species in 1890 by Joel Asaph Allen before it was lumped with the Cuban Oriole (Icterus melanopsis), Hispaniolan Oriole (Icterus dominicensis), and Puerto Rican oriole (Icterus portoricensis) into a single species by the ornithologist James Bond in his book "Birds of the West Indies". It wasn't until 2010 that all four birds were again elevated to full species status based on a combination of evidence from DNA, plumage and song.^[2][3] Since it was not recognized as a distinct species for so long, the Bahama oriole's preferred non-breeding season habitat is unknown and current estimates of its exact numbers remain vague.

Historically, the Bahama oriole has been known to inhabit only two major islands in the Bahamas: Abaco and Andros. It became extirpated from Abaco in the 1990s, and today remains only on Andros.^[4] It can be found on the three major islands of Andros: North Andros, Mangrove Cay, and South Andros. It is likely the oriole also occurs on some of the smaller cays, but current documentation is lacking. The species was recognized as critically endangered by Birdlife International in 2011^[5] with population estimates of 300 or fewer individuals remaining.^[6][7] However, this population estimate conducted by Price et al. (2011) was exclusive to populations in developed habitats; new findings suggest that the population size could be larger than previously estimated. ^[8]

The Bahama oriole's habitats during the breeding season include human residential areas, although there is recent evidence that they also use other habitats including pine and broadleaf "coppice" forest. Developed habitats are important for nesting since the species often uses introduced Coconut Palm (Cocos nucifera).^[9] Bahama Orioles were recently discovered nesting within the pine foresr, building nests in understory palmsLeucothrinax morrisii. More recently the Bahama Oriole has been recorded nesting in many other tree species including palms (Sabal palmetto, Coccothrinax argentata and bananas (Musa). Though the general habitats of the Bahama oriole during the breeding season is known, the preferred habitat of the oriole during the non-breeding season is still unknown, although birds can be encountered in all terrestrial habitat types.^[10]

The future of the Bahama oriole remains tenuous. The Shiny Cowbird (Molothrus bonariensis), a brood parasite that lays its eggs in the nests of other bird species, is naturally expanding its South American and West Indies range northward, and reached Andros in the mid-1990s.^[11][12] Although still relatively uncommon, the cowbirds regularly parasitize the nests of orioles in developed habitats.^[13][14] Also, in developed areas orioles frequently nest in Coconut Palm (Cocos nucifera), which are dying off because of lethal yellowing disease brought in with introduced palms.^[15] As of 2017, lethal yellowing disease has not spread to Mangrove Cay or South Andros. The bigger threats, however, are continued habitat loss from human development, introduced predators (including cats, rats, dogs and hogs) and stochastic processes that, because of the oriole's small population size, increase the risk of extinction. Ongoing studies are continuing to assess these risks and better estimate the remaining population size. ^[16]

References