AUDIE CORNISH, HOST:
Attention green iguanas in the state of Florida - consider yourselves on notice.
MARY LOUISE KELLY, HOST:
Yeah. The state is encouraging its homeowners to kill you whenever possible if you're on their property.
CORNISH: And if you're not on their property but on one of 22 public lands in South Florida, you can be killed there, too - no permit required.
KELLY: All this is posted on the Florida Fish and Wildlife Conservation Commission's recently updated website. It underscores the problem that iguanas have become.
CORNISH: When green iguanas first showed up in Florida in the 1960s, things were less tense.
JOE WASILEWSKI: Nobody really paid much attention. It was kind of cool to see a Godzilla-type animal in your yard.
CORNISH: That's Joe Wasilewski, a conservation biologist with a reptile consulting company in Florida.
WASILEWSKI: And then in the past 10 years or so, the population of iguanas has just gone out of control. They're literally all over South Florida now.
KELLY: Iguanas are an invasive species in Florida. They can grow longer than five feet - tail included - and they can wreak havoc.
WASILEWSKI: In Puerto Rico where there's over a million green iguanas, and they're not native, they've been known to undermine roads. Like, they burrow and I've seen roads collapsed. They also get into electrical transformers and cause massive power outages.
KELLY: On top of that, they can carry salmonella. And Florida says they could pose a threat to some native species.
CORNISH: Wasilewski says a warming climate might be driving this explosion. He says a long string of cold nights in 2010 almost wiped iguanas out in Florida.
WASILEWSKI: Since then, we haven't really had a cold snap. It's been warmer. These are tropical animals, and they really enjoy the warmer weather.
KELLY: Iguanas have sharp teeth and Wasilewski says killing them should be left to professionals.
CORNISH: And if all this sounds way too violent, think about landscaping.
WASILEWSKI: They love bougainvillea (ph). They love hibiscus. If you plant that in your yard, you're like a neon sign. Hey, iguanas, here I am.
CORNISH: And in South Florida right now, that is a recipe for trouble. Transcript provided by NPR, Copyright NPR.