To the unsuspecting person this might appear to be a pretty little bird. I thought so too when I saw it on holiday. I think, when it is in its native territory in Asia, it must be a delightful little bird. However, I have since discovered that due to the unprecedented increase of its range, in the year 2000 the IUCN Species Survival Commission declared it "one of the world's most invasive species and one of only three birds in the top 100 species that pose an impact to biodiversity, agriculture and human interests.
The IUCN declared this myna as one of the only three birds among the world's 100 worst invasive species. (Other two invasive birds being Red-vented bulbul and European Starling) It has been introduced widely elsewhere, including adjacent areas in Southeast Asia, Madagascar, the Middle East, South Africa, Israel, North America, Europe, Australia, New Zealand and various oceanic islands, including a very prominent population in Hawaii.
The Common Myna is a pest in South Africa, North America, the Middle East, Australia, New Zealand and many Pacific islands. It is particularly problematic in Australia. Several methods have been tried to control the bird's numbers and protect native species.
The Common Myna or Indian Myna (Acridotheres tristis), sometimes spelled Mynah, is a member of the family Sturnidae (starlings and mynas) native to Asia. An omnivorous open woodland bird with a strong territorial instinct, the Myna has adapted extremely well to urban environments.
The Common Myna is an important motif in Indian culture and appears both in Sanskrit and Prakrit literature. "Myna" is derived from the Hindi language mainā which itself is derived from Sanskrit madanā.
Threat to native birds
The Common Myna is a hollow-nesting species; that is, it nests and breeds in protected hollows found either naturally in trees or artificially on buildings (for example, recessed windowsills or low eaves). Compared to native hollow-nesting species, the Common Myna is extremely aggressive, and breeding males will actively defend areas ranging up to 0.83 hectares in size (though males in densely populated urban settings tend to only defend the area immediately surrounding their nests).
This aggressiveness has enabled the Common Myna to displace many breeding pairs of native hollow-nesters, thereby reducing their reproductive success. In particular, the reproduction rates of native hollow-nesting parrots in the bush land of eastern Australia have been reduced by up to 80% by the Common Myna (which was even able to out-compete another aggressive introduced species in the area, the European Starling).
The Common Myna is also known to maintain up to two roosts simultaneously; a temporary summer roost close to a breeding site (where the entire local male community sleeps during the summer, the period of highest aggression), and a permanent all-year roost where the female broods and incubates overnight. Both male and female Common Mynas will fiercely protect both roosts at all times, leading to further exclusion of native birds.