Although over 190 different species of bird have been seen on or around the central islands of Seychelles (and the number is increasing all the time), many of these are occasional visitors or vagrants while others, including all of the shore birds are migrants; they come here every year but do not breed here. Only 38 bird species breed here, and of these nine were introduced. Species that arrived in Seychelles with no help from man, and breed here, are called native species.
There are 19 native land bird species; the other natives are seabirds that spend much of their time at sea, returning to breed on the islands. Long distances over sea from mainland Africa and Asia, or from other islands in the Indian Ocean, are easily crossed by ocean-going seabirds, but are a big barrier to land birds that cannot feed as they fly, and will drown if they land in the sea. So it is very rare for new land bird species to reach Seychelles (although two species have reached the islands in recent years), and there are relatively few native land birds in Seychelles.
