# Leatherback Turtle — Facts, Threats & Conservation

*Dermochelys coriacea (Vandelli, 1761) — family Dermochelyidae*

> The leatherback is the world's largest turtle at up to 700 kg, the only sea turtle without a hard shell, and the deepest-diving reptile at over 1,200 m; it feeds almost entirely on jellyfish and is Vulnerable globally, with Pacific subpopulations Critically Endangered.

**IUCN status:** Vulnerable globally — Pacific subpopulations Critically Endangered  ·  **WARN range:** All tropical and temperate oceans, Feeds as far north as Norway and Alaska

## Quick facts
| Fact | Value |
| --- | --- |
| Maximum weight | 916 kg recorded; typically up to ~700 kg |
| Deepest dive | 1,280 m |
| Longest migration | Around 16,000 km |
| Diet | Almost entirely jellyfish and gelatinous plankton |
| Shell | Leathery skin over small bone plates — no hard carapace |
| Main threats | Fisheries bycatch, plastic ingestion, egg harvesting, beach loss |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Reptilia
- **Order:** Testudines
- **Family:** Dermochelyidae
- **Genus:** Dermochelys
- **Species:** Dermochelys coriacea

## Conservation status
- **Status:** Vulnerable globally; East and West Pacific subpopulations Critically Endangered
- **Population:** Atlantic populations relatively stable; East Pacific in the hundreds of nesting females
- **Trend:** Decreasing in the Pacific; mixed elsewhere
- **Assessed:** 2013
- **CITES:** Appendix I
- Sand temperature determines hatchling sex, so warming nesting beaches are producing female-skewed clutches. Nesting-beach protection is the cheapest and fastest intervention available.

## Key facts: Leatherback Turtle
- The leatherback is the largest turtle alive — typically up to about 700 kg, with a record individual at 916 kg.
- It has no hard shell. The carapace is leathery skin over thousands of small interlocking bone plates, ridged into seven longitudinal keels.
- It is the deepest-diving reptile, with a recorded dive of 1,280 m, and one of the deepest-diving air-breathing animals of any kind.
- Leatherbacks maintain a body temperature well above the surrounding water through size, insulating fat and counter-current heat exchange — a strategy called gigantothermy.
- The diet is almost entirely jellyfish. Backward-pointing spines called papillae line the throat and oesophagus so prey cannot slip back out.
- That diet is why plastic is lethal: a floating carrier bag closely resembles a jellyfish, and a swallowed one blocks the gut.
- The global listing is Vulnerable, but East and West Pacific subpopulations are Critically Endangered, having declined by more than 90%.

## The turtle with no shell
Every other sea turtle has a rigid carapace of fused bony plates covered in keratin scutes. The leatherback does not. Its carapace is a layer of tough, oil-saturated skin over a mosaic of thousands of small dermal bones, arranged into seven pronounced ridges running the length of the body.

This is not a deficiency but a specialisation. A rigid shell would be crushed by pressure at depth; a flexible one compresses and recovers. The structure is also lighter and more hydrodynamic, which matters for an animal that swims continuously across ocean basins. The trade-off is that adult leatherbacks have far less physical protection than other sea turtles, which they compensate for with sheer size — a full-grown leatherback has few predators beyond large sharks and killer whales.

## A warm-blooded reptile, more or less
Leatherbacks feed in water that would immobilise any other reptile, ranging as far north as Norway and Alaska and as far south as New Zealand and Chile. They manage this through gigantothermy: a very large body has a low surface-area-to-volume ratio and loses heat slowly, and the leatherback adds a thick insulating fat layer plus counter-current heat exchangers in the flippers, which recycle heat from outgoing blood into returning blood.

Continuous swimming generates the heat in the first place. A leatherback in cold water can hold a core temperature up to 18°C above the sea around it. It is not endothermy in the mammalian sense — there is no metabolic thermostat — but the practical result is a reptile with access to feeding grounds no other reptile can use.

## Why plastic kills leatherbacks
Jellyfish are around 95% water and provide very little energy, so a leatherback has to consume an enormous daily volume — estimates run to hundreds of kilograms — simply to sustain itself. It feeds by taking in anything gelatinous that drifts within reach, and its throat is lined with backward-pointing papillae specifically to stop soft prey escaping.

A floating plastic bag looks like a jellyfish, feels like a jellyfish, and once swallowed cannot be regurgitated because of those same papillae. It blocks the digestive tract, and the animal starves with a full stomach. Studies of stranded leatherbacks routinely find plastic in a substantial proportion of individuals examined. The feature that makes the leatherback an efficient jellyfish predator is the feature that makes marine plastic specifically, mechanically fatal to it.

## The Pacific collapse
The global Vulnerable listing conceals a much worse regional picture. Atlantic leatherback populations are relatively stable and in places increasing. Pacific populations have fallen by more than 90% and are assessed as Critically Endangered — the East Pacific population is estimated in the hundreds of nesting females.

The causes are bycatch in longline and gillnet fisheries, egg harvesting at nesting beaches, coastal development that destroys nesting habitat, and plastic ingestion. Nesting beaches are the single most tractable point of intervention: protecting a beach and its clutches is cheap relative to fisheries reform and delivers measurable results within a nesting season. Sand temperature also determines hatchling sex, so warming beaches are producing increasingly female-skewed clutches — a slower problem, and a harder one.

## What WARN does
WARN publishes free, sourced species education, including on marine plastic and bycatch — the two pressures doing most of the damage to leatherbacks. Understanding why a carrier bag is specifically lethal to this animal, rather than generally bad for the ocean, is the kind of detail that changes behaviour.

If this guide helps you understand wildlife and the pressures it faces, a gift to WARN supports habitat protection and free public education in our partner countries.

## Frequently asked questions: Leatherback Turtle
### How big do leatherback turtles get?
Adults typically reach 1.5 to 2 m and up to about 700 kg. The largest verified individual, stranded in Wales in 1988, measured nearly 3 m and weighed 916 kg — the largest turtle ever recorded.

### Why is it called a leatherback?
Because it has no hard shell. Its carapace is a layer of tough, oil-saturated leathery skin over thousands of small bone plates, ridged into seven keels, rather than the fused bony shell every other sea turtle has.

### How deep can leatherback turtles dive?
The deepest recorded dive is 1,280 m, making the leatherback the deepest-diving reptile and one of the deepest-diving air-breathing animals of any kind — deeper than most whales.

### What do leatherback turtles eat?
Almost entirely jellyfish and other gelatinous plankton. Because jellyfish are around 95% water, a leatherback must eat an enormous daily volume, and backward-pointing spines in its throat stop soft prey slipping back out.

### Why are plastic bags dangerous to leatherbacks?
A floating bag closely resembles a jellyfish, and the backward-pointing papillae that stop jellyfish escaping also make regurgitation impossible. Swallowed plastic blocks the gut, and the turtle starves.

### Are leatherback turtles endangered?
Globally they are listed as Vulnerable, but that masks severe regional decline. East and West Pacific subpopulations have fallen by more than 90% and are Critically Endangered, driven by fisheries bycatch, egg harvesting, coastal development and plastic.

### Where do leatherback sea turtles live?
Leatherback Sea Turtles live in All tropical and temperate oceans, Feeds as far north as Norway and Alaska. The leatherback is the world's largest turtle at up to 700 kg, the only sea turtle without a hard shell, and the deepest-diving reptile at over 1,200 m; it feeds almost entirely on jellyfish and is Vulnerable globally, with Pacific subpopulations Critically Endangered.

### How long do leatherback sea turtles live?
A precise wild lifespan for leatherback sea turtles is not firmly established in the sources cited on this guide. The leatherback is the world's largest turtle at up to 700 kg, the only sea turtle without a hard shell, and the deepest-diving reptile at over 1,200 m; it feeds almost entirely on jellyfish and is Vulnerable globally, with Pacific subpopulations Critically Endangered. Where longevity figures appear in the literature they vary by region, sex and whether animals are wild or captive.

## Sources
- [IUCN Red List — Dermochelys coriacea](https://www.iucnredlist.org/species/6494/43526147)
- [NOAA Fisheries — Leatherback turtle](https://www.fisheries.noaa.gov/species/leatherback-turtle)
- [CITES Appendices](https://cites.org/eng/app/appendices.php)

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Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/leatherback-turtle