This is according to a recent University of New South Wales study. From the Eurekalert article:

Introduced predators such as foxes and cats are twice as deadly as native predators to Australia’s unique native animals, a new study has found.

The new finding, published this week in the prestigious journal Proceedings of the Royal Society B, is the first confirmation of what has been a long-held hypothesis among scientists.

It also highlights the heavy continuing impact of these predators long after their introduction and that Australia’s fauna has been among the hardest hit in the world.

Experts believe that introduced “alien” predators are more dangerous than native predators because their prey, such as numbats and bettongs, are naïve to the hunting tactics of alien predators.

This is relevant to discussions of AI, intelligence-augmented humans, and synthetic life. Human beings are used to human modes of attack. We think we’ve seen it all. But we haven’t. If novel life forms devise attack strategies we can’t neutralize, then we could be in big trouble. The only way to win this game is not to play it at all: by creating a human-friendly AI that can counteract the risk from other potential nonhuman aggressors.