When we’re talking about turtles there are basically three groups. You’ve got the bi-environmental terrapins, which thrive on both land and sea; you’ve got tortoises, the slow moving, land-bound brutes; and finally there is the kind of turtle we will be discussing today, simply called “turtle”.
Yeah, I know we call them all turtles, but if we’re being scientific and as scuba divers, this is the real deal as far as turtles go!
Turtles call the ocean their home, use words like “gnarly” and “dude” and their favorite place is Koh Tao, home to both the Green and Hawksbill turtles. The Hawksbill is classified as critically endangered, but divers in Koh Tao still see them quite often.
There’s even one that’s really big and old named George. He makes regular appearances at Shark Bay where snorkelers often see him.
In honor of the Turtle, here are some ‘Turtley’ facts….
Turtles have been on this planet for a long time, roughly 220 million years. To put this into perspective, our species of humans only began to evolve about 200,000 years ago, so turtles are like 1,000 times older than us! To put this further into perspective, dinosaurs went extinct about 65 million years ago.
This means that turtles basically lived alongside dinosaurs for 150 million years. You could even say that turtles actually are dinosaurs! Either way, turtles have to be pretty tough, because they managed to avoid getting eaten by dinosaurs!
As a species Turtles have been around for quite a while, and individual turtles have extraordinarily long lifespans themselves.
The oldest turtle we know of is a 184-year-old giant Galapagos land tortoise.
You think turtles are slow and lazy, right? Wrong! Sea turtles can swim at bursts of speeds of up to 22 miles per hour (35 kph), and they often migrate thousands of miles in the course of a year. Green turtles can swim up to 35 miles per hour (56 kph)! The average turtle swims at a pace of 10 to 12 mph and walks at three to four mph.
Most sea turtles undergo long migrations, as far as 1,400 miles, between their foraging grounds and the beaches where they nest. Scientists can track the movements of sea turtles across oceans with satellites.
The leatherback turtle holds the record for longest migration, traveling over 10,000 miles each year in search of food, crossing over from Asia’s Pacific Coast to the West Coast of the United States foraging for jellyfish, seaweed, crabs, shrimp, sponges, snails, algae and mollusks.
Returning To Their Birthplace
The gender of turtles is determined by the temperature at which they hatch. Warmer temperature yield female turtles while colder temperatures yield male turtles.
Global warming throws a wrench into the turtle population. Hotter sand from increasing temperatures results in decreased hatching rates or complete nest failure. Increased sand temperatures alter natural sex ratios, so the turtles that do survive the hatch are predominantly female.
All turtles lay eggs; they find a place on land to lay their eggs, dig a nest into the sand or dirt and then walk away. No species of turtle nurtures their young. Mother sea turtles return to the beach on which they were born to lay their eggs. New research suggests that they use unique magnetic signatures to find their way back to the beach. Mother sea turtles lay around 110 eggs in a nest.
Aside from laying their eggs, turtles spend most of their lives in the water, meaning male sea turtles typically spend their entire lives without setting foot on dry land. Sea turtles are air-breathing reptiles, so they need to surface to breathe. They can hold their breath for several hours, depending upon the level of activity. A resting or sleeping turtle can remain underwater for up to seven hours!
Turtles in Outer Space
Russian turtles went to outer space! The Soviet Zond program launched Zond 5 on September 14, 1968. Fueled by the space race, the Soviet Zond 5 aimed for the moon. On board were flies, meal worms, plants, bacteria, and two Russian tortoises.
Zond 5 navigated around the moon, but failed to go into multiple orbits around it. Their capsule splashed down a week later in the Indian Ocean; the tortoises were unharmed. These tortoises spent a week in space and lost 10% of their body weight, but remained active after their trip around the moon.
Zond 5 didn’t mark the end of turtles’ cosmic career. Zond 7 and Zond 8 each carried multiple tortoises. And in 1975, tortoises aboard the Soviet Soyuz 20 broke another record when they spent 90 straight days in space, the longest time any animal has spent outside Earth’s atmosphere.
Turtles have not only been to space, they’ve been almost everywhere. They’re on every continent except Antarctica, as because they’re cold-blooded they’d get too cold.
An Endangered Species
There are seven species of marine turtles, and six of the seven are considered threatened or endangered!
The greatest threats to sea turtles are humans. Entanglement in fishing gear, poaching and illegal trade of turtle’s byproducts, coastal development, plastic and other marine debris, global warming, and ocean pollution are particularly harmful to the global turtle population.
Koh Tao’s turtles, both green and hawksbill turtles, are classified as endangered and critically endangered, respectively, so this problem hits close to home. In Koh Tao, entanglement in marine debris, such as fishing nets and plastic products is a topic that hits close to home.
Efforts are being made by conservation organizations like Eco Koh Tao to work with the local community to reduce marine waste and encourage turtle tourism.
Author: Jordan ‘Dingus’ Walden (PADI DM #377541)