In most places they're just a nuisance, but feral cats in Australia are considered pests. (Logan Mock-Bunting/For The Washington Post)

It's no surprise that Australia's recently announced plan to kill 2 million feral cats by 2020 received a lot of backlash. And after loud outcries from some very famous dissenters, the government is trying to defend its decision.

The cull isn't part of some cruel anti-cat agenda. In Australia, feral cats — which were introduced by the first European settlers — have become a huge threat to native wildlife. They're blamed for the extinction of several species unique to the country. Like many invasive species, they're a little too good at killing the locals — and as they thrive and breed, the problem is only getting worse.

[Australia is low on koala food and may need to kill some of the iconic creatures]

British singer Morrissey and French actress Bridgette Bardot, both veteran animal rights activists, have penned open letters to the government condemning the cull.  

"The cats are, in fact, two million smaller versions of Cecil the lion," Morrissey wrote, calling the cull "idiocy."

Bardot panned the "animal genocide" as "inhumane and ridiculous."

Because we domesticate them, branding cats as dangerous pests can be a tough pill to swallow. Even in Australia, pet cats are A-OK — as long as they're neutered, microchipped, and not allowed to roam around hunting.

In an open letter that begins by thanking Bardot for her commitment to protecting wildlife, Australia's Threatened Species Commissioner Gregory Andrews tried to defend his government's position.

[This hunter wants an endangered rhino’s head as a trophy. Looks like he’ll get it.]

"We are home to more than 500,000 species, most of which are found nowhere else in the world. Our animals and plants define us as a nation, so when we lose them, we lost a part of who we are as a country," Andrews wrote.

"But our wildlife has endured one of the highest extinction rates in the world. We have lost 29 unique Australian mammal species over the last 200 years. This represents 35 percent of the world's modern mammal extinctions and is the highest rate of mammal extinctions in the world."

[Scientists investigate the cat genome to see how wildcats turned into lazy furballs]

Much of this, Andrews explained, can be attributed to the fast proliferation and adept hunting skills of the feral cat population. Feral cats, he said, have been fingered as direct threats to at least 124 of the country's threatened species. 

He also pointed out that scientists estimate that Australia is home to about 20 million feral cats, and that they kill an average of five animals — bugs, lizards, small mammals and birds, and so on — each night. The cull of 2 million will focus on cats living in remote desert areas, where wildlife is most threatened. He pressed that the cull is just part of a larger effort, which will also include building fences to prevent feral cats from entering threatened areas.

Nobody is relishing the thought of killing a bunch of cats, clearly. And even if all 20 million were wiped out, Australia would still have some of the worst invasive species in the world to deal with. But while it may make pet owners cringe, the cull is environmentally sound — and necessary.

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