Sept. 19, 2008 -- Before his death two years ago this month, "Crocodile Hunter" Steve Irwin and his father discovered a unique turtle species that, as Irwin said, can "breathe through its bum." Researchers are now racing to save the rare and unusual turtle, Elseya irwini, which appears to be dying out as a result of human activities, according to scientists at James Cook Unviersity in Queensland, Australia. Irwin and his father Bob first found the turtle after accidentally yanking one up on a fishing line during a 1990 family camping trip. It was later determined that the turtle only lives in two places: the Broken-Bowen River and the lower Burdekin River in Australia. Ivan Lawler, who is now researching the turtle in hopes of saving it, told Discovery News the species was "probably always somewhat restricted in distribution, but changes in water quality, flow regimes and so on from human (induced) change" have reduced its range further. Lawler, a JCU ecologist, believes only 5,000 of the turtles exist in the wild today. The turtle's remaining habitat has extremely poor food sources, which could be why it evolved the odd breathing technique. Although the turtle can take in air from its nostrils, the second breathing method allows it to also absorb air from water that flows in through its behind, via an organ called the cloaca. It can therefore stay underwater for very long periods of time. "It might be that (cloaca breathing) allows them to maintain position in flowing currents while feeding, that it helps them to escape predation or that it allows them to reduce energy expenditure on surfacing and thus get by with a lower-energy diet," Lawler explained. He and physiologist Suzy Munns have found that the species "seems to have a very low metabolic rate, even for a turtle." |
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