Birds of Thailand; A Myna Dilemma

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Birds of Thailand; A Myna Dilemma
Birds of Thailand; A Myna Dilemma

The Common Myna is a bird frequently seen in Thailand. It will be one of the first species that any visiting bird watcher will notice as it forages around villages, farmland, parks and cities. However despite an apparently harmless disposition, it is a highly invasive species and has been declared as one of the greatest threats to native birds after land clearing.

The Myna (or Mynah), Indian Myna or Shepherds Starling (Acridotheres tristis) is an Asian songbird of the starling family. The specific name tristis is Latin for ‘sad‘or gloomy‘.

The species is placed in the genus Acridotheres (grasshopper hunters) by the French ornithologist Louis Jean Pierre Vieillot in 1816. Originally a native to open forests and woodland, the Myna proved to be synanthropic; that is a species that live near, and benefit from, an association with manmade habitats. The Myna is extremely well adapted to urban ecosystems. The number of Mynas has increased so rapidly that in 2010 the International Union for Conservation of Nature declared Mynas the world’s most dangerous neozoon; that is a species which establishes itself where they were not previously native to displace native plants or animals. Appearance The Mynah is typically 25 centimetres long with an average weight of 110 grams and a wing span of 140 mm. The bird is mainly brown in colour with a black hooded head and a chest of dark grey.

There is a white patch on the outer primaries and the wing lining on the underside is also white. The bare skin around the eyes, strong legs and the beak are yellow. Males and females look alike. This bird is a passerine, that is a species distinguished from other birds by the arrangement of their toes (three pointing forward and one back), which facilitates perching. Occurrence The Common Myna is originally from southern Asia, from Afghanistan to India to Sri Lanka. This is an abundant species typically found in open woodlands, savannahs, scrublands and fields, but also in populated urban areas.

Around Hua Hin they can be found in gardens, parks, downtown streets or even on the balconies of shopping malls. At sunset you can hear hundreds of them chatting together, for example around the municipality precinct. Behaviour The Common Myna is a gregarious bird outside the breeding season. At twilight large flocks gather to sleep in trees and call with gurgling, squeaking and clicking end tones. The function of communal roosting is to synchronise various social activities, avoid predators and to exchange information about food sources. The bird can imitate human voices and has a number of sharp calls and chatter.

This includes croaks, squawks, chirps, clicks, whistles and ‘growls’, and the bird often fluffs its feathers and bobs its head in singing. Common Mynas have been sold as cage birds all over the globe. Large flocks gathering at sunset may be seen AND heard around Hua Hin The Common Mynah screeches warnings to its mate or other birds in cases of predators in proximity or when it’s about to take off flying. Common Mynas are popular as cage birds for their singing and “speaking” abilities. Before sleeping in communal roosts, Mynas vocalise in unison, known as ‘communal noise’. Reproduction Common Mynas are believed to pair for life. The bird has a strong territorial instinct.

During the breeding season there is considerable competition for nesting sites. Favoured locations are in the walls and ceilings of buildings, making these birds a nuisance to humans. Nests are also placed in tree hollows used by native birds. Nests are quite messy and consist of a variety of materials. Leaves, grasses, feathers and assorted items of rubbish are common materials. Violent battles often erupt between occupants of nesting sites and the couple that wishes to evict an existing occupant. Each partner grapples with its opposite number and contestants drop to the ground secured in each other’s claws. Bills are jabbed ruthlessly at the opponent.

Finally, the defeated couple leaves to search for another site. Mynas are noted for their aggressive nesting behaviour and messy nests! The common myna uses the nests of other birds and easily takes to nest boxes. Evicting the chicks of previously nesting pairs has been recorded. This aggressive behaviour contributes to its success as an invasive species. Eggs are colored bright turquoise blue. Two to five eggs are incubated by both parents for about 17 to 18 days. The young birds fledge after a period from 22 to 24 days, but are still fed by their parents. Food and feeding The bird feeds on insects, arachnids, crustaceans reptiles and small mammals, but also seeds, grain and fruits. It forages on the ground and in foliage for insects, especially grasshoppers.

There’s much to admire about the success of this species and its ability to take advantage of the human habitat. However the Mynah’s dominance and impact on more vulnerable native species remains a dilemma yet to be resolved. About the Author George F. Gross niklaus or Dr George, as we like to call him, is a resident of Hua Hin who lists his special interests as ornithology, botany and morphology. Dr George has a PhD from Harvard and is the author of a book about tropical botany and compendiums of his interests in a very wide range of subjects including our diverse wildlife.

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