Whale Shark (Rhincodon typus)

Status: needs expert review. Conservation claims below cite the IUCN Red List and CITES; a science reviewer should confirm the assessment is current before this page is marked approved. The whale shark (Rhincodon typus) is the largest living fish — a slow-moving, filter-feeding shark of warm oceans worldwide.

At a glance

Field	Value	Source
Scientific name	Rhincodon typus	—
Guild	sharks-rays	—
IUCN status	Endangered (assessed 2016)	IUCN, 2016
Population trend	Decreasing	IUCN Red List
International trade	CITES Appendix II (since 2003)	CITES
Range	Tropical and warm-temperate oceans worldwide	IUCN Red List

Identification

The whale shark is unmistakable: a very large shark (the largest fish species), dark grey above with a distinctive pattern of pale spots and stripes, a broad flattened head, and a huge terminal mouth used for filter feeding. The spot pattern is individually unique — which is the basis for photo-identification citizen science (see below).

Ecology and behavior

Whale sharks are filter feeders, straining plankton and small fishes from the water. They are highly migratory and form seasonal aggregations at predictable feeding sites in several regions. Despite their size they are harmless to people. Detailed behavioral claims should be cited to published research and confirmed in review.

Conservation status and threats

The whale shark was assessed Endangered on the IUCN Red List in 2016, with a decreasing population trend. The IUCN update reported an inferred decline of more than 50% over roughly the last 75 years globally; the Indo-Pacific subpopulation was assessed as Endangered (a larger inferred decline) and the Atlantic subpopulation as Vulnerable. Principal threats are fisheries pressure (target and bycatch) and vessel strikes on these slow, surface-feeding sharks. International trade is regulated under CITES Appendix II (listed 2003).

These figures are reported as the cited authorities state them. A science reviewer should confirm whether a more recent assessment supersedes the 2016 listing.

How to observe responsibly

Whale shark tourism exists in several regions and is often regulated. This page does not provide approach guidance — follow the reviewed observation guide and the local regulations for your region, which set minimum distances, no-touch rules, and seasonal limits. Where aggregation sites are sensitive, this page intentionally keeps to regional granularity (ETHICS.md). If an operator encourages touching, feeding, or riding animals, that is a red flag, not an experience.

How you can help

• Contribute fluke/flank photos to recognized whale-shark photo-ID programs, which use the unique spot patterns to track individuals.
• Log sightings to a recognized citizen-science platform (see the iNaturalist dataset card).
• Support fisheries-bycatch reduction and vessel-strike mitigation through credible organizations.