Safari Sri Lanka: Migrants of Sri Lanka.

Sri Lanka supports a rich avifauna that stands at 495 species at present. This includes 240 species that are confirmed breeding residents who live year round and breeds in Sri Lanka. Out of the 240 breeding residents 33 are found only in Sri Lanka (endemic to Sri Lanka). Further, 21 species that are listed as breeding residents, also have migrant populations which include migrants of different races that occur in the country. The remaining species are considered as migrants.

The migrant birds can be further categorized in to

· Regular winter visitors that arrives in Sri Lanka around September and departs Sri Lanka around April (the period that coincides with winter season in the Northern hemisphere). Around 125 bird species recorded in Sri Lanka can be considered in this category. They can be further classified as very rare, rare, common, uncommon and very common migrants depending on the numbers that arrive and extent their distribution within Sri Lanka. Out of the regular winter visitors to Sri Lanka 10 species listed as very rare 44 are listed rare, 28 are listed as common, 22 are listed as uncommon and the rest as very common species. Further about 21 species that are listed as migrants also has small breeding populations, some of which are restricted to one or few locations. Sometime winter visitors may not exit Sri Lanka at the end of the migrant season. Such individuals are referred to as loiterers.

· Out of the 495 species recorded in Sri Lanka, 79 species are recorded only several times or periodically therefore, these birds though comes within the migrant category are classified as Vagrants as they do not show a regular pattern of visitation to Sri Lanka.

· Out of the 495 species recorded in Sri Lanka, 22 species are recorded only once or their inclusion in the Sri Lankan bird list is based on unconfirmed reports and therefore they are listed in the category defined as status unknown at present.

· Out of the 495 species recorded in Sri Lanka, 28 species (Such as Petrel’s Shearwater’s tropic birds, Booby’s, Frigate birds etc..) are recorded off the cost as they are mainly oceanic birds and use the maritime zone of Sri Lanka. Some of these species rarely come to land or get blown inland by wind and has been recorded at the site inlands.

The migrants that come to Sri Lanka arrive via two major routes, eastern and western route. The eastern route is used by birds arriving from Siberia, East Asia, northern and eastern India. They fly across the eastern edge of the Indian subcontinent and arrive on the north-eastern coast of Sri Lanka. Some of the birds that arrive through the eastern route include ducks, birds of prey and some waders. The majority of the birds that arrive in Sri Lanka use this route.

The western route is used by birds arriving from western Siberia, western part of India, middle east, eastern Europe and enters Sri Lanka via the north-western coast of Sri Lanka. Some of the species arriving through the western route includes Crakes, Plovers, Curlews, Godwits, Red Shanks, Snipes and harriers.

In addition to these routes is used by birds arriving from the far eastern region where they come through Andaman Islands, Birds that arrive from this route include Black-capped Kingfisher, Long-toed stint and Philippine shrike.

Having arrived in Sri Lanka disperses within the country. Some of these birds are restricted to the coastal zone while others will occupy both coastal as well as inland habitats. The migrants can be categorized in to two major groups depending on the habitats, those who predominantly occupy wetland habitats such as lagoons, estuaries, mangroves, salt marshes, mud flats, tanks, paddy fields and marshes and those who occupy terrestrial habitats such as forest, open scrublands, grasslands, and home gardens. Around 65 species of the regular migrants occupy wetland habitats while the rest occupy predominantly terrestrial habitats.

In terms of numbers, the largest migratory groups are the waders, ducks and coastal birds. In the family Charadriidae (Plovers) 42 out of 47 species are migrants. Likewise in the family Anatidae (Ducks) 11 out of 14 species are migrants. In the family Laridae (Gulls and Terns) 15 out of the 19 species are migrants of which many are restricted to coastal habitats such as slatterns, lagoons and beaches.

In terms of inland species that are occupying predominantly terrestrial habitats, Family Muscicapidae (Flycatchers) have the largest number of migrants were 24 out of the 46 species recorded in Sri Lanka is listed as migrant species. These include flycatchers, Tree-warblers, Thrushes, Warbles and Reed warblers. Likewise in Family Motacillidae (Wagtails and Pipits), 6 out of the 7 species are migrants. Further, among the family Hirundinidae (Swallows) 5 out of 7 species are migrants. Also among the members of the family Accipteridae (Eagles, Kites, Kestrels, Harriers etc...) 11 out of 25 species are migrants. Finally in the family Falconidae, except the resident Shahin falcon all other five species are migrants. Some of these terrestrial migrants such as Indian Pittas, Brown Shrikes, Wagtails, Blue-tailed bee eaters, Flycatchers, and Cuckoos can also be seen commonly in home gardens. Recent studies using bird banding shows that many of these migrants how site tenacity, i-e year after year they return to the same location.

Many of the habitats occupied by migrants, especially wetlands are being converted to other land uses. Further, many of these habitats also undergo change due to influence processes that are taking place elsewhere. A classic example is the Bundala National Park where, implementation of the Lunugamvehera project has resulted in a significant change in the salinity of the lagoons which has resulted in the habitat being unsuitable for many migrant species. Spread of invasive alien plant species such as Proposips juliflora in Bundala National Park, Vankali Sanctuary and aquatic invasive such as Ipomea Crassipes in Anavilundawa and many other wetland habitats has also rendered these habitat less attractive to migrant species. Likewise, conversions of coastal habitats such as mangroves, mud flats and salt marshes to prawn farms and slatterns have also resulted in loss of habitats for migrant species.

Therefore, Identifying habitats that are critically important for migrant species and conserving them would be a very important step towards the conservation of migrant birds in Sri Lanka.

Here are some migrant species we have captured....

Asian Paradise Flycatcher - Female.