A Sinuous Line Of Sea SnakesIn the Malacca Straits, on May 4, 1932, a surface congregation of sea snakes 10 feet wide and 60 miles long was observed. Helicopter pilots off Viet Nam and Pakistan have reported similar but much smaller concentrations. Groups of several thousand have also been noted in Panama Bay. This tendency to gather in great numbers at the surface is an enigmatic aspect of sea snakes. One possible answer may lie in the surface feeding habits of some species, such as the yellow-bellied sea snake. These creatures seem to float passively on the sea surface, feeding and reproducing, letting the winds and currents accumulate them in long drift lines.
(Minton, Sherman A., and Heatwole, Harold; "Snakes and the Sea," Oceans, 11:53, April 1978.)