Yesterday, we had the story of the homeless San Francisco woman who breeds rats in parks and homeless shelters. Today we have an example of what can happen when amateurs start breeding rats.

In Florida, there is a problem with an infestation of Gambian giant pouch rats on one of the Keys after a resident bred them years ago. If you’re wondering how big a Gambian giant pouch rat is, Wildlife officials are giving residents pointers on how to tell the difference between those rats and other species like raccoons and opossums; yes, rats the size of raccoons. These rats are a hardy bunch, too; officials have been trying to exterminate them since 2007.

The species first showed up around 1999-2000, according to the Miami Herald. The rats are described as weighing, on average, three pounds but going up to nine pounds, and between 20 and 35 inches long. A three foot long nine pound rat foraging around your house; I will never visit Grassy Key, Florida.