One is the lack of natural predators on the island.

They may also have fewer natural predators to control numbers.

Natural predators play an important role during periods of low population.

Without such areas, the fish are left vulnerable to natural predators.

With no natural predators other than themselves, the population exploded.

They've got no natural predators, so for a while they just have their way with everything.

There have always been many natural predators, like sharks, in the sea.

This also has the negative effect of threatening their traditional, natural predators.

Without any natural predators, the black bear population here is believed to be growing, pushing its way over the 10,000 mark.

And natural predators might come out, drawn by the blood scent.