Today is International Whale Shark Day! When most people think of sharks, they think of predators: the top carnivores of the sea. But whale sharks (Rhiniodon typus), the largest species of extant fish, don’t necessarily fit this description. Although they are carnivores, they don’t chomp down on their prey like most sharks. Instead, they open their wide mouths and suction water in. As the water moves through the shark’s mouth, it passes over filter pads that separates small organisms, like plankton, out of the water and the whale shark then expels the water out through its gills. They are also known to feed on small fishes, shrimp, and squid.
Like many other species of sharks, the International Union for Conservation of Nature (IUCN) estimates that the total number of living whale sharks has decreased drastically over the last century. Researchers studying whale sharks believe this population decline is due to overfishing and the unintentional killing of whale sharks as they are hit by propellers of large vessels or accidentally captured in fishing nets. In 2016, the IUCN added the whale shark to their red list of threatened species.
For International Whale Shark Day, learn more about these remarkable animals and what you can do to help conservation efforts. Additional resources are below. Feature photo is credited to Abe Khao Lak.