White Tailed Tropic Bird

Spotted this White tailed Tropic Bird (Phaethon lepturus) some 600 NM (1100 KM )off the Somalian Coast. The bird merely flew above my ship and did not land ,perch or return back for another sortie. The bird, is the smallest of the three other closely related tropic birds.The bird I believe is not native to India and may not be spotted here but is very common in the tropical oceans and its islands.