A hunt is on for a giant boa constrictor roaming free in a Western Sydney suburb. The 2.5m-long snake’s existence became known when it left its enormous shedded skin draped over a building site in Cascades Estate, Silverdale last Wednesday. “Observe and, if possible, photograph the animal. If it is moving try and watch where it goes. Do not make contact with the animal,” a letter sent from a government department to Silverdale residents reads. Native to Central America and prohibited outside of zoos, boa constrictors are not venomous but they bite and strangle their prey.