Okinawa rail (Gallirallus okinawae)

KingdomAnimalia
PhylumChordata
ClassAves
OrderGruiformes
FamilyRallidae
GenusGallirallus (1)
SizeLength: 30 cm (2)
Wingspan: 50 cm (2)
Weight435 g (2)

Classified as Endangered (EN) on the IUCN Red List 2007 (1).

By far the most conspicuous feature of the Okinawa rail is the vivid red colour of its bill and legs, which provide an exciting contrast against the black, white and brown plumage. Upperparts are olive-brown, while underparts are black, and strongly barred with white from the lower neck to the tail. The sides of the head are also black, with a distinctive white stripe extending from the base of the eye down the side of the neck (3). This almost flightless rail has an extremely short tail and long, strong legs (2) (3). Juveniles have paler upperparts with mottled white underparts (3).

As implied by its name, this rare bird is endemic to the southern Japanese island of Okinawa in the Nansei Shoto (Ryukyu) islands, where it is confined to the northern quarter of the island (4).

Found in a variety of habitats from sea level to the highest parts at 500 meters, mainly in primary and secondary subtropical broadleaf evergreen forest, often with a dense undergrowth of ferns. Damp areas and the margins of streams, pools or reservoirs are also frequently visited, as well as cultivated areas, scrub, meadows and grasslands close to forest (4). The bird requires standing water for bathing, and roosts in trees (2).

This almost flightless bird spends most of its time on the ground, where it forages for insects, snails, amphibians and lizards on the forest floor, although some food may also be taken from shallow water when it visits pools to bathe and drink (2) (4).

Monogamous, territorial pairs breed from May to July, building a nest on the ground or in the cavity of a tree stump, lined with dead leaves, grass and fern fronds (4). The usual clutch size is three to five eggs (3) (5).

The Okinawa rail only has one very small population with a tiny range on a single island, rendering it extremely vulnerable. Furthermore, both its range and population are undergoing continuing declines due to introduced predators and loss of forest to logging, dam construction and associated road-building and agriculture (3). Predation by mongooses, originally introduced to kill the poisonous habu snake, is thought to be having a significant impact on this bird, along with possible predation by feral dogs and cats (3) (4) (6).

The Okinawa rail is legally protected in Japan. Yonaha-dake and parts of Mount Ibu and Mount Nishime are designated as protected areas and in 1996 Yambaru was designated as a national park. Since 1970, conservation organisations have been campaigning for the protection of Okinawa’s forests and have bought some sites on Mount Yonaha to establish private wildlife reserves (3). The Ministry of the Environment of Japan has recently drawn up a protection plan for this rare bird, which includes an artificial breeding programme and culling of the bird’s predators (6). Only time will tell how successful these plans will prove to be in saving the species from extinction.

For more information on the Okinawa rail see:

Authenticated (26/09/07) by Mr Kiyoaki Ozaki, Bird Migration Research Center, Yamashina Institute for Ornithology, Japan.
http://www.yamashina.or.jp

  1. IUCN Red List (September, 2007)
    http://www.iucnredlist.org
  2. del Hoyo, J., Elliott, A. and Sargatal, J. (1996) Handbook of the Birds of the World – Hoatzin To Auks. Vol. 3. Lynx Edicions, Barcelona.
  3. BirdLife International (September, 2007)
    http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=2852&m=0
  4. BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.
  5. Yamashina Institute for Ornithology (September, 2007)
    http://www.yamashina.or.jp/yambarukuina/yambaru_mokuji.html
  6. Ministry of Foreign Affairs of Japan (September, 2007)
    http://www.mofa.go.jp/announce/announce/2007/6/1173808_828.html