Tuesday, September 12, 2006


C D Kaluthota & S W Kotagama

Field Ornithology Group of Sri Lanka, Department of Zoology, University of Colombo.

The IBA programme produces inventories of internationally recognized sites, which are vital for conservation of birds. These sites are identified using set of four standard global criteria. These criteria are designed to select representative areas of most important bird habitats, principally those that are under the most severe pressure. As birds are the best indicators for overall biological diversity, most IBAs will be significant for other animals and plants too. The reason for initiating a global IBA programme was obvious as throughout the world important sites for wildlife conservation are being destroyed, polluted or disturbed at an increasing pace. Habitat loss and modification is the single largest threat to biodiversity. Many threatened species are in fact threatened by the same factors at particular sites. Therefore, site-based conservation measures can conserve many species at the same time.

First task for the IBA programme was the identification of important birds for first three categories i.e. globally threatened species, restricted range species and biome restricted species. Ten species of globally threatened species are considered for the IBA programme since 14 of 24 globally threatened species recorded from Sri Lanka are vagrants. Twenty-four restricted range species including newly discovered Serendib scops owl are included in the second category. All nationally threatened species are also included in this category. Nineteen species are listed under biome-restricted species for this programme.

In Sri Lanka, 70 Important Bird Areas have been identified all over the island. From these IBAs, 47 supports globally threatened species while 56 sites facilitate restricted range species. 46 IBAs contained biome restricted species. For bird aggregations, 26 sites have been identified. Four IBAs namely Yala, Bundala, Gal Oya and Udawalawe are qualified under all four categories. 39 sites qualify for three of the four categories. According to the area of the IBAs, 25 sites are less than 1000ha in size while 27 IBAs are between 1000 and 5000ha. This shows the severity of fragmentation of the important areas. 71% of the IBAs are located in the South Western part of the island showing the importance of protecting wet zone forests, which are highly threatened by human disturbances.

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