Records of 'land-birds at sea': A review

Abstract

162 short reports on 'land-birds at sea' scattered in ornithological literature were reviewed with annotation (Those the original was not available were listed by titles only), with the divisions of: Western Atlantic (42), Eastern Pacific (8), Eastern Atlantic (37), Western Indian Ocean (13), the Mediterranean (28) (Most of reports before comprehensive paper of Moreau, 1953 were listed by titles only), the Red Sea (9), Western Pacific and Japanese waters (18) and South Asian Seas and Eastern Indian Ocean (7).Land birds, chiefly Passerines, have been recorded at sea mostly during migration seasons from several to some hundred miles offshore, but accidentally over a thousand miles. Even not far from the coast, less than some 20 miles, birds have been reported to come to ships exhausted and were seen dead on the water. These cases suggest that they migrate off the shore rather than along complicated coastal lines, even though they may encounter stormy weather and become exhausted. Some of them may be drifted hundreds of miles over the ocean by seasonal winds blowing out from the continent. The records plotted on the map suggest the pattern of such drifts along both sides of North America, east coast of Kamchatka, in Western Indian Ocean and North Atlantic.However, regular over-sea migrants have also been recorded in which the birds may not come to the ship or only some of them resting for a while or staying on board to feed on insects or food given by the passengers. Migratory hawks may live on such small birds on board. They have sometimes been brought back many miles by ship and reports of American birds crossing the Atlantic to the British Isles on board are increasing in literature. A Peregrine Falcon is supposed to have reached Japan from Hawaii on board a ship feeding on petrels and terns.Although rare, even resident birds have been recorded at sea. As suggested by Williams in New Zealand birds, these may be due to winds, but in some cases birds may first fly out to the sea by some innate factors. The accidental records of highly migratory birds such as the House Swallow, Lanius cristatus, Halcyon sancta, etc. (see the map) to unusual direction far over the ocean may also involve innate factors.