While sadly no longer found in Malaysia, let's use the leatherback turtle as an example here. The leatherback turtle can dive to great depths, as recorded by researchers who have equipped them with depth recorders. Leatherbacks have been recorded to dive over 1000 meters deep, which exceeds that reported of any air-breathing vertebrates with the possible exceptions of elephant seals and sperm whales. The shallowest dive depth occur at dusk and the deepest depth at dawn. This is probably due to the feeding of jellyfish that concentrates below 600 meters during the day and which moves into the surface around dusk. The leatherbacks dive almost continuously with only brief intervals at the surface for air.
Frank the photographer's first attempt at following a diving leatherback before giving up at 5 meters and surfacing for sweet, sweet air.
A study in 2008 shows that during the daylight hours, diving depths of two adult green turtles was shallow, around 1 - 4 meters. Researchers assume that the turtles were deliberately moving towards their destinations during this time. Between 7 - 8pm, the turtles began a diving pattern consisting of deep dives with a mean maximum depth of 35 - 55 meters. The shallow diurnal diving begins between 6 - 7am, after the nocturnal deep-diving patterns end. The adult female observed by researches made two dives in excess of 135 meters, and one male made several dives in excess of 100 meters. These are the deepest dives ever recorded for a naturally diving green turtle.
Frank second attempt at following a diving green, but plays it safe by keeping at only 2 meters. Nice going, Frank.
Impressive, aren't they? Well, as for how fast a turtle can crawl, I leave it to your judgement with this video (Do note that they are only baby turtles, and adult turtles can crawl much faster):
Frank tried to follow the turtles by going down on all fours. Sadly, we all know how that ended and here's a YouTube video instead. Way to go, Frank.
Enough about their speed. Now on to the last question, which is how sturdy a turtle's shell can be. Well, a turtle's shell can be important in several ways. A turtle's shell is able to protect the turtle from predators, and the shells of some turtles are so thick and strong that it can resist the bite of a large crocodile.
Not to be outdone by turtles, Frank volunteered to take a picture of an adult crocodile. Frank disappeared into the wilds and was never seen again. We will miss you, Frank.
Other turtles, such as Asian river turtles, often dive very deeply, where the water pressure is severe enough to crush their lungs if it wasn't for their shells. For turtles that live in very dry places, their shell provides a shield from the sun that helps the turtle from drying out too much. So, in a sense, a turtle's shell is a Kevlar vest with a built in air-conditioner.
Here's a picture of a Kevlar. Imagine it with a built in air-conditioner. How Frank must wish he had one of these before he went into the wilds shooting crocodiles.
While a turtle may seem awesome with all these capabilities, know that they are not immortal, and are still declining in numbers due to humans. So, let us all work together in preserving these magnificent creatures for our future generations to be awed.
Lo Khin Fu
Publicity & Creativity Team
Advanced Diploma in Mass Communication (Public Relations) Year 1
Tunku Abdul Rahman University College
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