Lord Howe Woodhen
From Wikipedia, the free encyclopedia
 |
||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||
|
|
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Gallirallus sylvestris Sclater, 1869 |
The Lord Howe Island Rail, Gallirallus sylvestris, also known as the Lord Howe Rail or popularly in Australia as the Lord Howe Island Woodhen, is a flightless bird of the rail family (Rallidae). It is endemic to Lord Howe Island off the Australian coast. It is a small olive brown bird, with a short tail and a downcurved bill. The Lord Howe Island Rail lives in sub-tropical forests, feeding on earthworms, crustaceans, fruit, and taking the eggs of shearwaters and petrels.
Woodhens mate for life and are usually encountered in pairs. They are territorial and will appear from the forest's understorey to investigate the source of any unusual noise. A mated pair will defend an area of approximately 3 hectares, with offspring being expellled from this area once grown. The population of birds is thus restricted by the amount of available territory.[1]
[edit] Decline and recovery
When explorers first discovered Lord Howe Island in 1788, they identified 15 bird species including the then common woodhen. Being flightless, curious, and having never been hunted, they became a readily available source of food for visiting sailors and the island's early human population. Since its discovery and the arrival of settlers on the island in 1834), nine of these 15 species became extinct. The woodhen declined in numbers until in the late 1970s, when surveys showed that the population had dropped to less than 30 birds, confined to the difficult to access summit regions of the island's two mountains, Mount Gower and Mount Lidgbird.[2]
A comprehensive study was done to determine the cause of the decline, which was eventually tied in to the introduction of feral pigs. The elimination of the pigs and other disruptive animals (goats), plus a programme of ex-situ conservation (captive breeding) which commenced in May 1980 (the first egg was laid in June 1980), allowed the Lord Howe Rail to recover its numbers. Today there are now about 250 birds,[3] which may be the optimal population size for the island.[4]
The analysis of the threats to the Lord Howe Rail, and the solution, is considered a model for conservation biology. A number of possible causes of the decline were on the island, from introduced rats to Tasmanian Masked Owls. However, only the elimination of the pigs would have saved the species from extinction, and identifying the cause and solution in a timely manner was crucial to the success of the programme.
Following the success story of the woodhen, there have been recovery efforts for other endemic species on Lord Howe Island, including the Lord Howe Island land snail (Placostylus bivaricosus) and the Lord Howe Island Currawong (Strepera graculina crissalis).
[edit] References
- BirdLife International (2006). Gallirallus sylvestris. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes a brief justification of why this species is endangered and the criteria used
