About the Tree Martin
The tree martin (Petrochelidon nigricans) is a member of the swallow family of passerine birds. It breeds in Australia, mostly south of latitude 20°S, and on Timor island. It is migratory, wintering through most of Australia, New Guinea, Indonesia east of the Wallace Line, and the Solomon Islands. It is a vagrant to New Zealand, where it has bred, and New Caledonia. This species is frequently placed in the genus Hirundo as Hirundo nigricans.
This is a bird of open woodland, preferably with large trees to provide nest holes. It is increasingly common in urban and suburban areas. The tree martin was formally described in 1817 by the French ornithologist Louis Vieillot under the binomial name Hirundo nigricans. The specific epithet is Latin meaning "blackish". Vieillot gave the type locality as "Nouvelle-Hollande" (New South Wales) but this has been corrected to Hobart, Tasmania. The tree martin is now one of ten swallows placed in the genus Petrochelidon that was introduced in 1851 by the German ornithologist Jean Cabanis.
Three subspecies are recognised: Wikipedia →