Pseudemydura umbrina nests in full daylight and typically during rain-bearing, low pressure weather fronts. The nesting action pattern of P. umbrina is unique because the nest cavity is constructed with the forelegs, with the female being head-down in the hole; during this stage, the hindlegs are only used to push soil material, which accumulates beside the female, behind and out of the hole. Nest digging in P. umbrina may have evolved from the typical turtle nesting pattern by an alteration and expansion of the stage of nest site preparation, which now incorporates the actual digging of the nest chamber, and a drastic reduction, or omission, of the typical stage of digging the egg cavity with the hindlegs. The other stages of nesting in P. umbrina follow the well-defined sequence of steps of chelonian nesting.
|Publication status||Published - 1993|