Population, distribution, habitat use and breeding of Gurney's Pitta Pitta gurneyi in Myanmar and Thailandстатья из журнала
Аннотация: Gurney's Pitta Pitta gurneyi was not seen in the wild for over 30 years before its rediscovery in a small area in southern Thailand in 1986. In 2003, it was found over a much larger area in southern Myanmar (Burma) after an even longer absence of records. This paper reports the results of recent research on both populations. In Myanmar, birds were found in a high proportion of visited sites, including sites up to 40 km further north than any previous records in the country. Occupied forest sites had a higher density of seedlings, saplings, bamboo and rattan than unoccupied forest sites, suggesting a preference for regenerating forest. There was no evidence of a decline in the species's likelihood of occurrence up to at least the highest visited altitude of 230 m. Maximum entropy models suggested a potential range size of between 3,200 and 5,800 km2 and the predicted range extended just over the border into Thailand, suggesting that birds might persist there. Population estimates for southern Myanmar ranged from 9,300 to 35,000 territories, with a mid-point estimate of 20,000 territories, based upon range sizes modelled from different parameters and a range of territory densities estimated from Thailand. The population in southern Thailand was estimated at between 15 and 20 territories in 2003, 2005 and 2007, and there was a reduction in the historic rate of forest loss in the core range over the same period, suggesting that long-term declines have been at least temporarily contained by recent conservation intervention. However, nesting success in Thailand was very low, due to heavy nest predation by cat snakes Boiga. Nests were usually built close to waterlogged areas and damp gullies, and nestlings were fed almost exclusively on earthworms. Occupied sites in Thailand had a higher density of seedlings, saplings, spiny palms and rattans, but sparser ground cover and a lower density of large trees and bamboo, than forests in Myanmar, indicating their secondary nature. Occupied and unoccupied sites in Myanmar were structurally more similar to each other than either was to occupied sites in Thailand. The results suggest that the species might inhabit a wider range of altitudes, slopes and forest types than previously thought, and so might persist in previously unsurveyed areas and might survive or even benefit from a degree of forest disturbance. However, the species's conservation-dependent status in Thailand and accelerating forest clearance in Myanmar suggest that forest protection measures are urgently needed to secure its long-term future.
Год издания: 2009
Авторы: Paul F. Donald, SIRIRAK ARATRAKORN, THURA WIN HTUN, Jonathan C. Eames, Htin Hla, Somying Thunhikorn, Kriangsak Sribuarod, PINYO TINUN, Sein Myo Aung, Sa Myo Zaw, Graeme M. Buchanan
Издательство: Cambridge University Press
Источник: Bird Conservation International
Ключевые слова: Wildlife Ecology and Conservation, Species Distribution and Climate Change, Avian ecology and behavior
Открытый доступ: bronze
Том: 19
Выпуск: 04
Страницы: 353–353