Genus CabalusHutton 1874 Higher classification Gallirallus | Phylum Chordata Family Rallidae Scientific name Cabalus modestus Rank Species | |
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Similar Bird, Dieffenbach's rail, Rallidae, Gallirallus, Tahiti rail | ||
The Chatham rail (Cabalus modestus) is an extinct flightless species of bird in the family Rallidae. It was endemic to New Zealand. Genetic similarity with Gallirallus dieffenbachii is why many view this species as part of the genus Gallirallus.
Cabalus modestus was endemic to Chatham, Mangere and Pitt Islands, New Zealand. It was first discovered on Mangere in 1871, and 26 specimens collected there are known from museum collections. It became extinct on the island between 1896 and 1900. The species is also known from 19th century bones from Chatham and Pitt Islands. It is likely to have occurred in scrubland and tussock grass.
Extinction
Its extinction was presumably caused by predation by rats and cats (which were introduced in the 1890s), habitat destruction to provide sheep pasture (which destroyed all of the island's bush and tussock grass by 1900), and from grazing by goats and rabbits. On Chatham and Pitt Islands Olson has suggested that its extinction resulted from competition with the larger Dieffenbach's rail Gallirallus dieffenbachii (also extinct), but the two species have been shown to have been sympatric on Mangere. Gallirallus dieffenbachiii and G. modestus had a common volant ancestor but both were flightless, their sympatry suggests parallel evolution after separate colonisation of the Chatham Islands .