Critically Endangered
Mariana Crow
Corvus kubaryi
Mariana Crow is a perching bird in the family Corvidae (order Passeriformes) — Corvus kubaryi, recorded as Critically Endangered.
Appearance
The Mariana crow is a small black crow with a bluish-black gloss on its tail, and a greenish-black gloss on its back, underparts, head, and wings.
An adult weighs about 9 ounces (260 g) and is about 15 inches (38 cm) long.
Range and habitat
The Mariana crow inhabits second growth and mature forests, as well as coastal strand vegetation, but nests only in native limestone forest. The crow currently is only found on the island of Rota. It disappeared from southern Guam in the 1960s and from central Guam in the 1970s, mostly inhabiting Andersen Air Force Base.
The Mariana crow is also persecuted by residents of both islands who see it as an obstacle to development. In 1993, a National Wildlife Refuge was established on Guam to preserve the remaining forest, and birds were translocated from Rota.
Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.
Habits
Perching birds hold with three toes forward and one back. A named island starling or leafbird in this catalog is a wild population, not a cage type.
In crisis
On Guam there are no remaining native Mariana crows, the population having been wiped out by the introduction of the brown tree snake. On Rota the population has declined to fewer than 200 individuals, the main threats here being the reduction of suitable habitat because of development and predation. The International Union for Conservation of Nature has rated the bird as being "critically endangered".
On Guam, the Mariana crow's decline is primarily due to predation by the introduced brown tree snake (Boiga irregularis). On Rota, many other threats endanger the crow, among them homestead development, resort and golf-course construction, agricultural settlement, nest-predation from introduced rats, the Mariana monitor lizard (Varanus tsukamotoi), typhoons, predation from feral cats, disease, and competition with the black drongo (Dicrurus macrocercus).
Mariana Crow is Critically Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.
Sources
Written for this catalog from the English Wikipedia article on Mariana Crow, Wikidata item Q1196375. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.
