The Pig-Nosed Turtle is a freshwater turtle from northern Australia and New Guinea. The only living member of its genus, Carettochelys insculpta are unique in the world of river turtles. The Pig-Nosed Turtle, or Fly River turtle has fins instead of front feet, making it resemble a marine turtle. Carettochelys insculpta is named for its snout-like nose and front facing nostrils, which allow the turtle to take in air at the waters surface more easily.
The wild population of Pig-Nosed turtles have declined over 50% in the last thirty years for many reasons. Many are smuggled out of Indonesian New Guinea, destined for the exotic pet trade or the wildlife food markets of China.
The Pig-Nosed turtle is an omnivore, eating fruits, vegetables, molluscs and crustaceans. Like many turtle species, Carettochelys insculpta reaches maturity late in life. Females don't reach breeding age until they are 18+ years old. This species is most remarkable for breeding strategy. They breed during the dry season and lay their eggs in sandy river banks. Remarkably the fully developed babies will not hatch until certain environmental conditions trigger the hatching process, but will rather stay in a hibernation state until ready. The Pig-Nosed turtles will only start to hatch when either the eggs are immersed in water or pressure drops significantly (signalling an approaching storm). This gives the hatchlings several advantages. Being nearly entirely aquatic, the turtles rely on the river for survival. Thus the flood induced hatching ensures the turtles will have a ready food source and also shelter in the environment they are most comfortable in. This strategy also ensures the clutch of eggs all hatch at the same time giving safety in numbers.
The following clip from David Attenborough's Life in Cold Blood illustrates this unique reproductive strategy very eloquently. Enjoy: