Identification
Extinct. Formerly endemic to Tristan, in the Tristan da Cunha island group, and not known from other islands. Likely survived until the 1870s, and last observed in 1873. The causes of extinction include rats, cats, and humans. The moorhen was a medium-sized, black bird, similar to Eurasian Moorhen, which is an occasional vagrant to the mid-Atlantic islands. It superficially resembled Gough Moorhen, and was formerly considered conspecific. Gough Moorhen was later introduced to Tristan, and this led to confusion as to whether the original Tristan Moorhen went extinct at all, until DNA studies showed significant differences between the two.