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Wildlife Guide · Asia & Oceans

Coconut Crab

Birgus latro

The world's largest land arthropod and tree-climbing island giant

IUCN: Vulnerable
Coconut crab climbing a palm tree trunk at night showing its large orange-brown body and powerful claws

Image: Photo: Franz Eugen Köhler, Köhler's Medizinal-Pflanzen / Wikimedia Commons (Public domain)

In brief

The coconut crab (Birgus latro) is the world's largest land-living arthropod, a giant terrestrial hermit crab found on tropical islands across the Indo-Pacific. Adults reach a leg span of about 1 m (3 ft) and weigh up to roughly 4 kg (9 lb).

By the WARN Research & Conservation TeamChecked against IUCN Red List & CITES sourcesLast updated

The coconut crab (Birgus latro) is the world's largest land-living arthropod, a giant terrestrial hermit crab found on tropical islands across the Indo-Pacific. Adults reach a leg span of about 1 m (3 ft) and weigh up to roughly 4 kg (9 lb). Famous for climbing trees and cracking open coconuts with powerful claws, it is a long-lived omnivore that may survive 40 to 60 years. The IUCN lists it as Vulnerable.

0.4 m

Typical length

4 kg

Typical weight

4 km/h

Top speed

40 yrs

Lifespan

Figures sourced from Wikipedia — Coconut Crab, Wikidata — Coconut Crab .

Coconut Crab: Quick Facts

Vital statistics and key facts about the Coconut Crab
Scientific name Birgus latro
Diet Omnivore (coconuts, fruit, seeds, carrion)
Habitat Tropical islands across the Indo-Pacific
Lifespan Possibly 40–60 years
Weight Up to about 4 kg (9 lb)
Leg span Up to about 1 m (3 ft)
Conservation status Vulnerable (IUCN)

Scientific Classification

Scientific classification of the Coconut Crab
Kingdom Animalia
Phylum Arthropoda
Class Malacostraca
Order Decapoda
Family Coenobitidae
Genus Birgus

Conservation Status

IUCN Status
Vulnerable (IUCN Red List category)
Population
Global population not compiled for this guide
Trend
See the IUCN Red List assessment
Assessed
See the IUCN Red List assessment
CITES
See CITES appendices

Conservation figures are drawn from the IUCN Red List and CITES; this guide links to the authoritative sources rather than restating population counts.

Key Facts: Coconut Crab

  • The coconut crab is the heaviest land arthropod on Earth, with a leg span reaching about 1 m (3 ft) and a body mass of up to roughly 4 kg (9 lb).
  • Coconut crabs are accomplished climbers that scale palm trunks and other trees, sometimes several metres up, to reach fruit or to escape the heat.
  • Despite the name, the coconut crab is a broad omnivore rather than a coconut specialist.

Size and body

The coconut crab is the heaviest land arthropod on Earth, with a leg span reaching about 1 m (3 ft) and a body mass of up to roughly 4 kg (9 lb). Unlike its smaller hermit-crab relatives, an adult no longer carries a borrowed shell, instead hardening its own abdomen for protection. Its front claws are extraordinarily strong, capable of a pinch measured among the most powerful of any animal for its size. The body is armoured in a thick exoskeleton that ranges from bluish to reddish-orange depending on the island population.


Climbing and coconuts

Coconut crabs are accomplished climbers that scale palm trunks and other trees, sometimes several metres up, to reach fruit or to escape the heat. They are named for their habit of husking and cracking coconuts, using their claws to strip the fibrous outer layer and hammer through to the flesh inside, a task that can take days. On the ground they are slow, moving at only around 4 km/h, so climbing gives them access to food that faster animals cannot reach. Their grip is strong enough to carry objects heavier than their own body.


Diet and feeding

Despite the name, the coconut crab is a broad omnivore rather than a coconut specialist. It eats fallen fruit, seeds, nuts, the pith of toppled trees, and carrion, and will scavenge almost anything organic it encounters at night. It also feeds on other crabs and has been recorded taking small live animals when the chance arises. A keen sense of smell, unusual among crustaceans and more like that of insects, guides it to food across the forest floor.


Life cycle and breeding

Coconut crabs are terrestrial as adults but remain tied to the sea for reproduction. After mating on land, a female carries her eggs on the underside of her abdomen and then releases the hatching larvae into the ocean, usually at high tide. The tiny larvae drift and develop in the water for several weeks before settling and, like young hermit crabs, occupying small shells while they mature on land. Once large enough, they abandon the shell for good and never return to the water, growing slowly over decades.


Distribution and habitat

The species is found on tropical islands and coastlines throughout the Indo-Pacific, from the western Indian Ocean to islands scattered across the central Pacific. It favours forested coastal areas with plenty of cover, sheltering by day in rock crevices or burrows lined with fibre and emerging to forage after dark. Because populations are isolated island by island, numbers vary widely from place to place. It has vanished from some islands where humans are numerous and survives best on remote, undisturbed land.


Conservation status

The coconut crab is listed as Vulnerable by the IUCN, with populations declining across much of its range. Its slow growth, late maturity, and long lifespan of possibly 40 to 60 years make it slow to recover from losses. Hunting for food, habitat loss, and predation of larvae and juveniles by introduced animals all put pressure on island populations. Several countries now regulate harvesting, setting size limits and protecting breeding females to keep local populations from collapsing.

What WARN Does

WARN does not run a dedicated coconut crab programme — this guide is part of the World Animal Rescue Network's free educational library. The coconut crab faces documented conservation pressure in the wild, which is why clear, sourced public information about it matters. Building public understanding of species like the coconut crab supports the broader conservation awareness that underpins WARN's partner-led rescue work across its network.

If clear, science-based wildlife guides like this help you understand and value animals, please consider supporting the World Animal Rescue Network's educational and rescue work so we can keep producing them.

Coconut Crab: Frequently Asked Questions

How big can a coconut crab get?

Coconut crabs are the largest land arthropods in the world. A full-grown adult can span about 1 m (3 ft) from leg tip to leg tip and weigh up to roughly 4 kg (9 lb).

Can coconut crabs actually open coconuts?

Yes. They use their powerful front claws to strip the fibrous husk and then hammer and pry at the shell until it cracks, reaching the flesh inside. The process can take several days for a single coconut.

Do coconut crabs climb trees?

They do. Coconut crabs regularly climb palms and other trees, sometimes several metres up, to reach fruit or escape the heat of the ground. Climbing is important because they move slowly on land, at only about 4 km/h.

How long do coconut crabs live?

They are remarkably long-lived for an invertebrate, possibly reaching 40 to 60 years. They grow slowly and mature late, which is one reason their populations recover slowly from over-harvesting.

Are coconut crabs dangerous to humans?

Their claws are among the strongest of any animal for their size and can deliver a painful, even injurious pinch, so they should be handled with care. They are not aggressive predators of people, but a grip from a large adult is difficult to break.

Where do coconut crabs live?

They live on tropical islands and coasts across the Indo-Pacific, from the western Indian Ocean to the central Pacific. As adults they are fully land-dwelling, returning to the sea only to release their larvae.

What do coconut crabs eat?

Coconut crabs are omnivores, eating coconuts, fruit, seeds and carrion. Despite the name, they are broad feeders rather than coconut specialists, using a keen sense of smell to locate fallen fruit, nuts and organic matter across tropical island forest floors at night.

Sources & References

Population figures, conservation status and biological facts on this page are drawn from authoritative scientific and intergovernmental sources.

Terms used on this page

Plain-English definitions, from our wildlife and conservation glossary.

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