For example, on 12 May 1998, we observed from a boat 5 whale sharks circling a
large school of cubera snapper that were spawning just below the sea surface. These
whale sharks lifted their upper jaw above the sea surface, gulping in water, milky white with fish spawn.
An examination of video footage shot from the surface on 5 April 1999 revealed
that most sharks feeding at the surface maintained a forward motion while feeding. The top of their upper jaw was kept above the water surface, and the inside of the top of their mouth was just at the surface.
Two whale sharks were filmed swimming in this manner, leaving their jaws above the surface for 12 and 13 s, respectively.
On each of the 5 evenings that we witnessed this behavior, darkness halted observations while surface feeding was still continuing.