The science on that is settled. The cats hate the birds. The cats chase the birds. The cats eat the birds.
So when birds on an island are threatened by cats, what would you do? Why you'd remove the cats! Logically, the birds would thrive and all would be perfect. The island would begin to heal. The science is settled, after all.
So what happened with this simple little solution to the problems of cats killing birds?
Behold the results of a system more complex than just two elements:
It seemed like a good idea at the time: Remove all the feral cats from a famous Australian island to save the native seabirds.
But the decision to eradicate the felines from Macquarie island allowed the rabbit population to explode and, in turn, destroy much of its fragile vegetation that birds depend on for cover, researchers said Tuesday.
Removing the cats from Macquarie "caused environmental devastation" that will cost authorities 24 million Australian dollars ($16.2 million) to remedy, Dana Bergstrom of the Australian Antarctic Division and her colleagues wrote in the British Ecological Society's Journal of Applied Ecology.
"Our study shows that between 2000 and 2007, there has been widespread ecosystem devastation and decades of conservation effort compromised," Bergstrom said in a statement.
The unintended consequences of the cat-removal project show the dangers of meddling with an ecosystem — even with the best of intentions — without thinking long and hard, the study said.
Huh. Unintended consequences of thinking they knew that the problem of cats killing birds would obviously be solved by removing cats. And the birds suffered anyway.
To be fair, I'm sure the computer models showed that the birds and island would thrive in the absence of cats.