Amazing footage of a whale shark "surfing" on top of a school of mackerel off the coast of Mafia Island in Tanzania.

The video, filmed on December 3, shows the giant creature appearing to rest on top of the thick school of fish, essentially gliding through the sea.

A whale shark (Rhincodon typus) feeds on zooplankton alongside a school of fish (Indian mackarel - Rastrelliger sp.) off Mafia Island in Tanzania. Here, whale sharks often feed on sergestid shrimps in the same area as smaller, plankton-feeding fishes. The whale shark did not eat any of the fish. Smaller fishes also sometimes use the large whale sharks to hide from predatory fishes.

Whale sharks are the largest fish in the world, growing up to 20 m in length, although most whale sharks that are seen by marine tourists are juveniles less than 8 m long. Whale sharks aggregate in certain coastal areas, including at Mafia Island in Tanzania where I shot this video earlier in December 2016. They are filter feeders that prey chiefly on very small zooplankton.