Tahitian Red-billed Rail

Taxobox
name = Tahitian Red-billed Rail
status = EX
status_system = iucn3.1
extinct = late 18th - 19th century


regnum = Animalia
phylum = Chordata
classis = Aves
ordo = Gruiformes
familia = Rallidae
genus = "Gallirallus"
species = "G. pacificus"
binomial = "Gallirallus pacificus"
binomial_authority = (Gmelin, 1789)
synonyms =
*"Rallus pacificus"Gmelin, 1789
*"Hypotaenidia pacifica"Rothschild, 1907
*"Rallus ecaudatus"("non" Miller 1783; "nomen nudum")

The Tahitian Red-billed Rail ("Gallirallus pacificus") or Tahiti Rail is a poorly-known extinct species of rail. It once occurred on Tahiti, where, apparently on the second voyage of James Cook in 1773, one was acquired and described by Johann Reinhold Forster as well as painted by his son Georg. What became of Forster's specimen is not known. This flightless species was probably derived from the ubiquitous Buff-banded Rail stock. The Tahitian name was transcribed as "ebōnā" or "ōmnā" (see also below).

Due to a major taxonomic mix-up, the name "Rallus ecaudatus" was commonly used in the mid-late 20th century to refer to this bird. This is, however, in error, as that taxon is an extant subspecies of the Buff-banded Rail, today known as "Gallirallus philippensis ecaudatus". Also, at least once, the Tahitian bird has been referred to by the scientific name of the Samoan Wood Rail, "Gallinula pacifica", in a major scientific work.

Extinction

Little can be said about the species' disappearance. As with most extinct Pacific rails still encoutered alive by scientists, introduced predators are the most likely suspects for its extinction. It may have become extinct soon after Cook's visit, but the bird was still reported to have existed until recently in 1844. Considering that the bird was probably very cryptic, this may have been true. Even more astounding is the claim by locals that it was found until approximately the 1920s on the islet of Mehetia, although this seems hardly true since the distance between Tahiti and Mehetia is about 100 km and the Red-billed Rail was, as mentioned above, flightless. The native name "tevea" seems to refer to the Mehetia bird. If indeed a rail existed on Mehetia, it is more probable that it was a closely related, but distinct species. Considering that Mehetia was not permanently inhabitedVerify source|date=August 2007 and thus probably free from predators, it is even quite likely that the late extinction date of that bird is correct. Whether a distinct species could evolve and persist on tiny (2.3 km²) Mehetia is less certain, especially as the island seems to have been subject to heavy volcanic activity in the last 2000 years ; an alternative explanation could be that birds were translocated from Tahiti by Polynesian woodcarvers for provisioning during their stays on Mehetia.

References

* Database entry includes justification for why this species is extinct
* Gmelin, Johann Friedrich (1879): [Description of "Gallirallus pacificus"] . "In: Systema Naturae (13th edition)" 1, part 2: 717.