If you don't know what a Mammalian Gene Drive is, read this

The year is 2050. The place, New Zealand. Technological advances have dramatically changed the lives of the island’s human inhabitants, but on first blush, its animals remain untouched.
 
Except for one curious thing: all invasive rodents have vanished from the island. Rats, possums and other predators once wreaked havoc on the country’s rare endemic species. For centuries, mass influxes of invasive species trashed agricultural productivity, spoiled the country’s pristine beauty, and brought iconic species—such as the flightless kiwi—to the brink of extinction.
 
But no more. In 2050, not a single invasive predator remains.
 
This may sound like science fiction, but it is, in fact, the goal of New Zealand’s wild new plan to rid itself of all vertebrate pests. Relying solely on traditional approaches like poison and traps is out of the question; instead, the ambitious project is developing new genetic engineering techniques to render invasive species infertile, exterminating them from within their own DNA.