Today’s Factismal: The Fitzroy River Turtle is also known as the “bum breathing turtle” because it can use bags in its butt to breathe underwater.
Imagine that you are a turtle. If you are like most turtles, you’ll need to spend lots of time underwater, because that’s where the food is and where the predators aren’t. But, like all turtles, you breathe air. So how can you do both at the same time?
Some turtles, such as the leatherback turtle, simply hold their breaths for as long as ten minutes at a time. Others, such as the pig-nosed turtle and red-eared slider, turn their noses into snorkels that allow them to breathe while staying submerged. But some turtles have developed a unique method of breathing – they use bags in their butts to extract oxygen from the water.
Known by scientists as cloacae bursae (Latin for “sacs in the sewer” because they are hollow sacs and because they are in the all-purpose exit known as a cloca) and by everyone else as “butt bags”, these sacs are lined by a thin membrane that is surrounded by lots of blood vessels. The thin skin allows oxygen to cross from the water to the turtle’s bloodstream and for carbon dioxide to take the opposite journey; that is, for the turtles to breathe. In most turtles, the clocae bursae are just auxiliary lungs but in the Fitzroy river turtle, they are the primary means of respiration. Some scientists estimate that the Fitzroy river turtle gets as much as 70% of its oxygen from its butt bags!
Like many turtles around the world, the Fitzroy river turtle is in danger, due to the encroachment of man on its habitat. Because turtles frequently have to cross roads to move from place to place, and because cars move much faster than turtles, the turtles are frequently run over. Today, scientists are attempting to identify the places where this happens the most frequently so that they can focus conservation efforts where they are most needed. If you’d like to help, the report turtle (and other!) roadkill to Linking Landscapes: