SYDNEY • Australia's northern quolls are small animals with big appetites - and they are eating themselves to death.

Nocturnal marsupials about the size of a squirrel, quolls once roamed all of Northern Australia. But a disposition to eat just about any animal smaller than themselves led to a steady diet of cane toads, an invasive and poisonous species. Since the 1900s, quoll populations have plummeted. In parts of Cape York Peninsula in north-eastern Australia, toad-eating quolls were completely wiped out, and the animal has been considered endangered nationwide since 2005.