Galapagos Giant Tortoise: 23 Interesting Facts

Giant Galapagos Tortoise, Galapagos Islands, Ecuador

Giant Galapagos Tortoise

When it comes to wildlife-watching opportunities, the Galapagos Islands are second to none. Blue-footed boobies waddle along the shores, marine iguanas lounge on the rocks, and Galapagos penguins splash around in the waters, not to mention sea lions, fur seals, and sea turtles everywhere you turn. However, of the 56 endemic species found on the islands, there is one that always stands out: the Galapagos Giant Tortoise.

Bigger than any tortoise you will have seen before, these creatures are the wildlife celebrities of the Galapagos, but there’s so much more to these fascinating reptiles than meets the eye. From mating rituals and quirky habits to their unique history—here are 23 interesting facts about the Galapagos Giant Tortoise.

1. Galapagos Giant Tortoises are the largest tortoises in the world

The name probably gave it away, but it’s true—these tortoises are gigantic! These are the largest tortoises in the world, measuring more than 5 feet long and up to 5 feet wide for an adult male. Compare this to the average pet tortoise, which can grow to lengths of between 10 and 18 inches, and you’ll get an idea of how unique this species is.

A typical male Galapagos Giant Tortoise weighs in at more than 500 pounds, although females tend to be smaller, weighing an average of 250 pounds. If you think that sounds big, wait until you hear the record—the largest tortoise recorded reached almost 6 feet in length and weighed an enormous 919 pounds.

2. They live for more than a hundred years

Not only are these tortoises impressive in size, but their longevity is equally admirable. The average Galapagos Giant Tortoise lives to be more than 100 years old, one of the longest lifespans of all vertebrates (but not the longest—that honor goes to the shark, the oldest of which lived a mind-boggling 272 years old!).

The oldest known tortoise from the Galapagos lived to a record age of 176, which is still quite remarkable. She died back in 2006 at Australia Zoo and was believed to have been among one of the specimens collected by Charles Darwin during his 1835 trip to the Galapagos Islands. A true example of the survival of the fittest!

3. The Galapagos Islands were named after the tortoise

You probably assumed that the Galapagos Giant Tortoise, along with species like the Galapagos Penguin, the Galapagos Sea Lion, and the Galapagos Land Iguana, were named after their habitat. In fact, it was the other way round.

When the Galapagos Islands were discovered by Spanish explorers back in 1535, the gigantic tortoises made such an impression, they decided to name the islands after them. ‘Galapago’ was the old Spanish word for ‘saddle’, which described the shape of the tortoises’ shells.

4. Tortoise riding used to be a popular activity

Speaking of saddles, the tortoises’ saddleback shells were the inspiration behind an unlikely pastime for early visitors to the islands. Riding the tortoises was once a popular activity, with participants climbing up onto the top of the shell and holding onto the rim.

Charles Darwin even reported attempting it himself. As he approached the tortoises, they would retreat into their shell, allowing him to climb aboard. He wrote how it was tricky to keep his balance once the reptiles started moving again.

However, these tortoises were clearly not designed to be ridden by humans, and after realizing that this practice could be harmful, it has now been made illegal to ride or attempt to ride the Galapagos tortoises.

Galapagos Giant Tortoise Saddleback Example

Example of saddleback shell of Galapagos Giant Tortoise

5. There are three different types of tortoiseshell

Galapagos Giant Tortoises have three distinctive shell types, which have evolved to suit their natural environment. Saddlebacked tortoises have raised shells with a thick, upturned rim. They evolved on drier islands and have long necks and limbs, allowing them to reach low-hanging branches or bushes further off the ground. Dome-shaped tortoises have rounded shells with shorter necks and limbs. These reptiles are found on wetter, more humid islands, where the tortoises can easily graze on fallen leaves and low vegetation. There is even a third type of shell known as an ‘intermediate,’ which is a combination of the two.

6. They move sloooowly!

Tortoises are hardly known for their speed, and the Galapagos Giant Tortoise is just as laid-back when it comes to going places. The average speed of an island tortoise is just 0.16 miles per hour (0.26 kilometers per hour). That’s more than 17 times slower than the average human walking speed of 2.8 miles per hour (4.5 kilometers per hour).

Their slow-moving nature doesn’t mean they don’t get around, though. Female tortoises can travel up to four miles to lay their eggs, and males can clock up to more than eight miles (13 kilometers) over two days during mating season. Just don’t expect them to get there quickly!

7. Galapagos Giant Tortoises can survive a year without food

Tortoise’s legs aren’t the only things that move slowly. Galapagos Giant Tortoises also have a notoriously slow metabolism, meaning they take a painstakingly long time to break down and digest food stores.

This has an upside, though. The tortoises can survive up to a year without eating anything at all, instead surviving off their own body fat.

8. They can go a year without water

Even more incredible is the fact that Giant Tortoises can go an entire year without drinking water. The average tortoise can store gallons of water in their bladders, ensuring they stay hydrated, even in the hot and humid climate of the Galapagos Islands.

9. They were once hunted for meat

In a sad twist of fate, this amazing adaptation of surviving without food or water once threatened the tortoises’ survival. When 19th-century sailors visited the islands, they soon learned the advantages of these giant tortoises as a meat source.

Flipping the tortoises on their backs and storing them in the holds of their ships, the tortoises provided sailors with a source of fresh meat on their lengthy sea voyages. The fact that they didn’t need to feed or water them just added to the convenience.

Thankfully, this cruel practice has long since been banned, but not before it threatened to wipe out the species. After two centuries of being captured and eaten, numbers of Galapagos Giant Tortoises on the islands have reduced from an estimated 250,000 to around 19,000.

Sleeping Galapagos Giant Tortoise

Sleeping Galapagos Giant Tortoise

10. Galapagos Giant Tortoises sleep up to 16 hours a day

When they aren’t slowly ambling around the islands, the Galapagos tortoise likes nothing more than a leisurely lie-in or an afternoon siesta. The tortoises sleep an average of 16 hours each day.

Tortoises generally sleep through the night, but they also enjoy napping throughout the day. Look out for the lazy land-lubbers along the rocks and beaches of the Galapagos Islands, dozing in the sun. Typically, tortoises retreat into their shells to sleep, but you might also see them sleeping with their heads in the mud or sand.

11. They don’t hibernate

While in colder climates, tortoises often hibernate throughout the winter months, Galapagos Giant Tortoises don’t typically hibernate. The Galapagos Islands’ location on the Equator means that temperatures are warm and consistent year-round; therefore, the tortoises do not need to hibernate.

12. Galapagos Giant Tortoises don’t swim

While many people confuse turtles and tortoises, the most important difference is that tortoises do not swim. Galapagos Giant Tortoises are buoyant, thanks to their shells, so they are able to float, but you won’t ever see the creatures in the water. However, it is believed that the tortoises could once swim or at least survive in water, and there have been a few examples of this happening.

Scientists believe this is the answer to the long-debated question of how the Galapagos tortoises came to live on the islands. DNA tests have shown their ancestors to be from South America, but the closest landmass to Galapagos is Ecuador—a 620-mile (1,000-kilometer) journey by sea! The most common theory is that a pregnant female or breeding pair made the expedition some two million years ago, swimming or floating out to the islands and thereby introducing the species to the Galapagos.

13. Galapagos Giant Tortoises don’t have teeth

Think of a tortoise, and you probably imagine its large shell, stumpy feet, and scaly necks, but did you know that these Tortoises don’t have teeth? Instead, they use the sharp edges of their mouth to bite vegetation and have strong, bony jaws that allow them to snap vines and squash fruits.

Galapagos Giant Tortoise Eating Grass

Galapagos Giant Tortoise eating grass

14. They are vegetarian

Despite their enormous size, the Galapagos Giant Tortoise doesn’t eat much. Their meal of choice is green, and they typically graze throughout the day, eating small amounts of grass, leaves, and other vegetation. Popular food sources on the islands include some unusual choices, such as prickly cactus and the fruits of the manzanillo tree, which are poisonous (and often fatal) for humans.

Of course, they don’t need to eat a lot thanks to their slow metabolism—it might take a tortoise up to three weeks to fully digest a meal.

15. Tortoises are creatures of habit

As a visitor to the islands, you probably won’t be around long enough to notice, but those who have studied Galapagos Giant Tortoises noticed a common trend. They don’t like to change their routines!

The tortoises are creatures of habit and often have a set daily routine. They will eat, sleep, and travel at the same times and typically follow the same routes day in day out. This simple existence is only thrown into disarray if there’s a good reason—a threat from predators or extreme weather conditions, for example.

16. Galapagos Giant Tortoises communicate using body language

Have you ever wondered what noise a Galapagos Giant Tortoise makes? The answer is not a lot! Female tortoises make no sounds at all, and while males do groan while mating, that’s the only time they get vocal.

The rest of the time, tortoises communicate using body language. A stand-off between two males, for example, would involve the tortoises glaring at each other with open mouths, each raising their heads as high as possible. The tortoise with the highest head typically wins the ‘fight,’ and the confrontation is soon over.

17. You can’t separate a tortoise from its shell

A unique fact about tortoise shells is that they are actually part of the animal’s skeleton. Therefore, it’s impossible to separate a tortoise from its shell. Galapagos Giant Tortoises are born with their shells, and the shell grows along with the tortoise, reaching full size at around 20 to 25 years old. They will retract into their shells to protect themselves from predators, to stay cool in the sun, and to sleep.

Despite the tortoise’s large body mass and immense weight, the shell itself isn’t that heavy. The shells are made up of air chambers, like a giant honeycomb, making them a lot lighter than you might think.

18. You can tell a tortoise’s sex by its shell

Another fascinating feature of the Galapagos tortoise’s shell is that you can tell the tortoise’s gender by looking at the undershell. Female tortoises will have a slight outward (convex) curve on the undershell, while those of male tortoises have a slight inward (concave) curve.

This is harder to tell on younger tortoises, though, so determining the sex of a tortoise under 20 years old is much more challenging.

Galapagos Giant Tortoises Mating

Galapagos Giant Tortoises mating

19. They have unusual mating rituals…

The tortoise mating season on the Galapagos Islands runs from January through August, during the hottest part of the year. Male tortoises will follow the scent of sexually mature females and may compete against each other for the attention of their mate (see our note on tortoise ‘fighting’ above!).

When a suitable mate is found, the male tortoise will knock the female with its shell and nip at her feet until she lies down and draws her legs under her shell. Males will often follow females for three or four days before mating, and the act itself can take up to 20 minutes.

20. …and even more unusual breeding rituals

After mating, female tortoises typically make their nests on the island’s sandy beaches, using their hind legs to dig a hole about 12 inches (30 cm) deep. She will lay her eggs (typically between 2 and 16) in the hole, then cover it with sand or soil, and urinate on it to make a protective ‘mud’. The incubation period is between four to five months, with most tortoise hatchings occurring between December and April.

Another curious fact is that the temperature of the incubation can determine the sex of the tortoises. Cooler temperatures mean more males will be born, while a warmer temperature means more females. It’s unlikely that female tortoises are aware of this, but it’s been a useful detail for conservation and breeding programs.

21. Baby Galapagos Giant Tortoises aren’t quite so giant

Tortoise eggs are around the size of a tennis ball, and tortoise hatchlings typically measure just 2.4 inches (6cm) in length and weigh in at about 2.8 oz (80g). That means that the tortoises may grow to more than a thousand times their initial bodyweight.

These baby tortoises are left to fend for themselves immediately after birth, and sadly, most will never reach sexual maturity (this can take up to 40 years in the wild!). It’s estimated that most tortoises die within the first 10 years of their life.

22. Galapagos Giant Tortoises are endangered

Hunting by pirates and sailors, as well as attacks on tortoise nests and hatchlings by feral pigs, rats, and dogs, saw the Galapagos Giant Tortoise reach near-extinction. As a result, many subspecies of the tortoises are critically endangered, with some believed to be extinct, and the Galapagos Giant Tortoise is now a protected species under Ecuadorian Law.

There is some good news, though. Conservation efforts by the Galapagos Conservancy have seen numbers increase across the board. One species, Chelonoidis hoodensis, from Española Island has bounced back from just 14 tortoises to more than a thousand thanks to dedicated breeding programs. Scientists also recently confirmed that the Chelonoidis phantastica species from Fernandina island is not extinct, as was previously assumed.

23. Galapagos Giant Tortoises can only be found on the Galapagos Islands

The Galapagos Giant Tortoise is undoubtedly one of the most iconic animals on the Galapagos Islands, and, as with many of the island’s endemic species, you won’t be able to see these tortoises in the wild anywhere else in the world.

Galapagos tortoises were once native to many of the Galapagos Islands, but today they can be found on seven islands. The best sightings are on Pinzon, Española, and Isabela islands, but you’ll also see them on San Cristóbal, Santa Cruz, and Santiago islands.

If you don’t have a chance to visit the Galapagos Islands, the only chance to witness these creatures will be in zoo conservation areas. San Diego Zoo and London Zoo are two places where you can see Galapagos Giant Tortoise, but nothing beats the opportunity to admire them in their native habitat.

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