Celebrating the World’s Biggest Fish: Whale Shark Day

August 30 is International Whale Shark Day! This day was established to raise awareness around the importance of whale sharks to marine ecosystems and their dwindling population numbers, and to encourage conservation efforts to protect these gentle sharks.

The whale shark, (Rhincodon typus), is the largest fish in the ocean, found in tropical and temperate oceans, in deep water and in coastal areas. Growing as large as 14 meters and 20 tonnes (45 feet, 6000 pounds) whale sharks are filter feeders, feeding on plankton, fish eggs but also small fish and squid.

According to the IUCN, the Indo-Pacific population of the whale shark is thought to have reduced 63 percent over the past 75 years. The population in the Atlantic is thought to have been reduced more than 30 percent. Globally, the populations are continuing to decrease. Because of this, whale sharks are classified as endangered.

Threats to this species include killed as bycatch, in fisheries for fins, oil, and meat, vessel strikes, and habitat loss. The fins are used as decoration. Loss of food source and climate change are adding pressure on whale shark’s survival increasing threat of extinction.

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Listed as “Endangered” under the International Union for Conservation of Nature and Natural Resources (IUCN), these sharks are listed under Appendix II of the Convention on the International Trade of Endangered Species (CITES). The whale shark population has declined over 50% in the last 50 years. However, areas of tourism may provide regional protection for this species.
Shark Stewards is working with the US Fish and wildlife and the Shark Research Institute to increase trade barriers and international protection for this species at the Convention for the International Trade of Endangered Species 2022.