Galápagos tortoises, also known as Galápagos giant tortoises, are the world’s largest tortoises. They weigh up to 400 kg (882 lb.) and measure up to 1.8 m (70 in.) long.
Galápagos tortoises live on the Galápagos Islands, situated 970 km (600 mi.) off the coast of Ecuador.
Scientists believe the first tortoises arrived on one the islands 2-3 million years ago by drifting on their own or atop vegetation rafts from mainland South America. Once there, their numbers grew and the tortoises populated the other islands in the archipelago.
With a poor sense of hearing, Galápagos tortoises rely primarily on sight and smell to navigate their world. They are not particularly fast, walking at speeds around 0.3 km/h (0.2 mph).
Galápagos tortoises spend 16 hours a day resting. They are cold-blooded and take 1-2 hours in the morning to bask in the sun in order to warm their bodies.
Galápagos Tortoise Shells
Like all tortoises, Galápagos tortoises are a kind of turtle. They have shells which are made of bony materials and covered with scutes (plates) made of keratin.
Galápagos tortoises have two main shell types: domed and saddle-backed. Saddle-backed tortoise shells have an upward curve on the front of the shell, which allows them to raise their heads and reach vegetation higher up.
Long Necks
Galápagos tortoises have long necks. In fact, their necks can be 60-90 cm (2-3 ft.) long! However, when threatened, they can pull their heads and legs into their shells for protection.
What Galápagos Tortoises Eat
Galápagos tortoises graze on grasses, woody shrubs, fruits, and cactus pads. They will drink lots of water when available, but they can survive for up to a year with no food or water!
Symbiotic Relationship with Finches
Often, small birds sit on Galápagos tortoises’ backs. Galápagos tortoises have a symbiotic relationship with Galápagos finches. A finch will fly in front of a tortoise, and then the tortoise will extend its neck and legs and stay still.
The finch will then hop on and eat the ticks from the tortoise’s skin folds. This benefits the tortoise who gets parasites removed from its skin as well as the finch who gets an easy meal.
Reproduction
In general, Galápagos tortoises breed during the hot season, which is January-May, but mating can happen at any time. The female tortoise then travels to nesting areas on the sandy coast, digs a hole, and lays a clutch of eggs.
Saddle-back tortoises lay about 2-7 eggs and domed tortoises lay about 20-25 eggs. The eggs, which are spherical and the size of a tennis ball, incubate for 130 days. They are warmed by the sun’s heat.
Studies have shown that eggs laid in cooler, higher elevations result in male baby tortoises, and eggs laid in warmer, lower elevations result in female babies.
When baby Galápagos tortoises hatch, they weigh only 50 g (1.8 oz) and measure 6 cm (2.4 in) long. Their shells are soft, which makes them vulnerable to predators like feral pigs, cats, dogs, hawks, and black rats.
Adult Galápagos tortoises have no natural predators (other than humans). They have a very long lifespan, averaging over 100 years. In fact, one captive Galápagos tortoise named Harriet lived over 175 years.
Conservation Status
There is debate about whether the 15 different kinds of Galápagos tortoises are subspecies or if each kind is a full species in its own right. Two kinds of Galápagos tortoises, the Pinta giant tortoise and the Floreana giant tortoise, are now extinct.
Whalers and fur sealers hunted the tortoises in the 1800s, and their populations never recovered.
The last Pinta giant tortoise, named Lonesome George, was discovered on Pinta Island in 1971 and was brought to the Tortoise Breeding and Rearing Center on Santa Cruz Island in hopes of finding him a mate. Unfortunately, scientists were unable to find another Pinta giant tortoise, and when he died in 2012, that was the end of that species.
Today, all Galápagos tortoises still living are classified as vulnerable or endangered by the IUCN Red List. Threats to Galápagos tortoises include poaching and habitat destruction.
What You Can Do to Help
You can help Galápagos tortoises by supporting efforts to conserve their habitat. You can also donate to the Galápagos Conservation Trust.
Galápagos Tortoise Range
Galápagos tortoises live on the Galápagos Islands, situated 970 km (600 mi.) off the coast of Ecuador.
More Galápagos Tortoise Resources
- Galápagos Conservation Trust
- Galapagos Conservancy’s “Lonesome George” page
- San Diego Zoo Wildlife Alliance Library’s Galapagos Giant Tortoise page
- Pilcher, Helen. BBC Science Focus. “How did tortoises reach the Galapagos Islands?”
Quick Fact Sheet
Common Name(s): Galápagos Tortoise, Galápagos Giant Tortoise
Scientific Name: Chelonoidis spp.
Animal Type: reptile
Size: Up to 1.8 m (70 in.) long
Weight: Up to 400 kg (882 lb.)
Lifespan: 100 years
About the Author
Abi Cushman is a contributing editor of Animal Fact Guide and My House Rabbit. She is also an award-winning author and illustrator of funny picture books for kids, including Wombats Are Pretty Weird and Flamingos Are Pretty Funky.
To learn more and to download free activity sheets, visit AbiCushman.com.
