Basking Shark (Cetorhinus maximus) — Endangered

Basking shark (Cetorhinus maximus) feeding at the surface with its mouth wide open. — Basking shark (Cetorhinus maximus) filter-feeding.
Image: Greg Skomal / NOAA Fisheries Service, Public domain, via Wikimedia Commons.

At a glance

IUCN category: EN · Endangered
Animal group: Fish
Population trend: Decreasing
FaunaHub record reviewed: 2026-06-16
Checked against IUCN: Matches source — IUCN's 2021 global assessment of Cetorhinus maximus says EndangeredChecked 2026-10-09 against IUCN's Red List export published 2026-07-28 · assessment

Conservation overview

The basking shark is the second-largest fish in the world, a gentle filter-feeder that strains plankton with its huge open mouth. It is assessed as Endangered.

Despite its enormous size, it is harmless to people.

Range & habitat

Temperate coastal and open waters worldwide.

Major threats

Threats below are drawn from the authoritative sources listed on this page. For the current, complete assessment, see the IUCN Red List.

Past targeted fishing
Bycatch and disturbance
A very slow reproductive rate

Why it matters

A giant, slow-reproducing filter-feeder, the basking shark is a flagship for protecting plankton-rich seas and recovering from historical overfishing.

Gallery

A basking shark at the surface. — Basking shark (Cetorhinus maximus).
Image: , Public domain, via Wikimedia Commons.

Sources

Sources for Basking Shark

IUCN Red List — look up Basking Shark (authoritative status)
FishBase

Frequently Asked Questions

What does the basking shark eat?

Plankton. It swims slowly with its huge mouth open, filtering tiny organisms from the water through its gill rakers — it is harmless to humans despite its size.

Why is the basking shark Endangered?

Published assessments cite past targeted fishing, bycatch and disturbance, and a very slow reproductive rate that makes recovery slow. See the IUCN Red List.