The problem: a fence that protects eastern quolls threatens long-necked turtles in Booderee national park at Jervis Bay. The solution? Turtle tunnels. Nine water-filled tunnels were built beneath a 82-hectare fence that surrounds the botanic gardens which keep out feral predators, providing a safe passage for the reptiles to go between watering holes. Over a period of 123 days, conservationists recorded 73 successful instances of the turtles using the tunnels