# Basking Shark (*Cetorhinus maximus*)

> The basking shark (Cetorhinus maximus) is the world's second-largest fish, a gentle filter feeder that swims open-mouthed through plankton blooms in cool temperate seas including the UK, Ireland, California, and New Zealand. Adults may reach 8 m and several tonnes and are listed Endangered after historic fisheries and slow reproduction.

- **Category:** Fish
- **Conservation status (IUCN):** Endangered
- **Range:** Cool temperate oceans worldwide, including the UK, Ireland, California, and New Zealand.
- **Canonical page:** https://globalanimalguide.org/animals/basking-shark/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Chondrichthyes
- **Order:** Lamniformes
- **Family:** Cetorhinidae
- **Genus:** Cetorhinus

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Cetorhinus maximus |
| Diet | Filter feeder (plankton) |
| Habitat | Coastal and shelf surface waters |
| Lifespan | Around 50 years in the wild (varies by population and captivity). |
| Weight | About 4000 kg typical adult mass (sex and region vary). |
| Top speed | Up to roughly 20 km/h when moving at speed. |
| Conservation status | Endangered (IUCN) |

## Ocean sun-filterer

Enormous gill rakers strain zooplankton while the shark cruises at the surface — the habit that inspired the name. Dorsal fins breaking the surface are often mistaken for great whites at a distance.

## Plankton, not seals

Diet is copepods and other zooplankton; teeth are tiny and unused for biting large prey. They may dive deep between surface feeding bouts. Across its range it is tied to coastal and shelf surface waters, and field accounts emphasise this species’ distinctive ecology rather than generic habitat labels.

## Cool coastal shelves worldwide

Temperate coastal and shelf waters including the UK, Ireland, California, New Zealand, and other cool seas where plankton aggregations form.

## Endangered slow breeder

Targeted historically for liver oil and meat. Late maturity and long gestation keep recovery slow; IUCN lists basking sharks Endangered. Many range states now protect them.

## Frequently asked questions

### Do basking sharks eat people?

No — they filter plankton and pose virtually no predatory threat to humans.

### How big do basking sharks get?

Commonly 6–8 m; only the whale shark grows larger among fish.

### Why are basking sharks Endangered?

Past commercial hunting and very slow life history left depleted populations.

### Where can you see basking sharks in the UK?

Summer surface feeding off western Scotland, Isle of Man, Cornwall, and other plankton-rich coasts.

### Are basking sharks related to great whites?

Both are lamniform sharks, but basking sharks are filter feeders, not active seal hunters.

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Source: Global Animal Guide (https://globalanimalguide.org/animals/basking-shark/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.