Etienne Littlefair / Northern snapping turtle (Elseya dentata) female walking along a creek bed, Pine Creek region, Northern Territory, Australia.

Joel Sartore / Photo Ark / Southern New Guinea stream turtle (Elseya rhodini) head portrait, private collection. Captive, occurs in New Guinea.

Joel Sartore / Photo Ark / Southern New Guinea stream turtle (Elseya rhodini) portrait, private collection. Captive, occurs in New Guinea.

Bruce Thomson / White throated / Southern snapping turtle (Elsaya albagula) on rocks in stony stream, algae covering shell, Mary River, Queensland, Australia.

Etienne Littlefair / Looking up at Irwin's turtle (Elseya irwini), large adult female found on the surface, possibly breathing or warming up, North Johnstone River near Malanda, Australia. August.

Etienne Littlefair / Northern snapping turtle (Elseya dentata) swimming away in mid-water column, Daly region, Northern Territory, Australia. June.

Etienne Littlefair / Northern snapping turtle (Elseya dentata) swimming, possibly surfacing for air, Daly region, Northern Territory, Australia. June..

Etienne Littlefair / Northern snapping turtles (Elseya dentata), resting in an underwater cave shared with other northern snapping turtles, Katherine region, Northern Territory, Australia. July.

Etienne Littlefair / Northern snapping turtle (Elseya dentata), resting in an underwater cave shared with other northern snapping turtles and Sooty grunters Katherine region, Northern Territory, Australia. July.

Etienne Littlefair / Northern snapping turtle (Elseya dentata) walking along the bottom of a deep, sandy creek, Daly region, Northern Territory,July

Etienne Littlefair / Northern snapping turtle (Elseya dentata) walking along the bottom of a deep, rocky creek, Katherine region, Northern Territory, June

Etienne Littlefair / Northern snapping turtle (Elseya dentata) about to surface for air, Katherine region, Northern Territory, June