Natural enemies of parakeets in Australia?

The correct answer is kookaburra and lace monitors.

Kookaburras are large, carnivorous birds found in Australia and New Guinea. They are known for their loud, distinctive call and their habit of killing and eating small animals, such as parakeets. Lace monitors are large lizards found in Australia and Indonesia. They are also carnivorous and known for preying on small animals, including parakeets.