A black-footed ferret,. This animal is endangered and getting more so thanks to a disease carried by its prey.

An endangered black-footed ferret. Photo: Shutterstock

The black-footed ferret has been endangered for quite some time. They were actually listed as extinct in 1979, but a population was rediscovered in 1981, and as of 2011 there were about 1,000 of them in the wild. Since then, that number has dropped to about 300. That’s a 70 percent loss over five years, and it’s primarily due to the sylvatic plague, which is spreading quickly throughout the population. The ferrets are primarily being infected by prairie dogs, which are their chief prey and primary food source.

Black-footed ferrets are North America’s only native ferret. The fact that they depend on prairie dogs for their food and shelter only exacerbates the havoc the disease is causing to their population.

If something isn’t done soon, the black-footed ferret could be completely wiped out in the wild. But there is a plan to help. The United States Fish and Wildlife Service wants to coat M&Ms in peanut butter laced with an oral vaccine, which will be dropped from drones every 30 feet or so.

The candies are intended for the prairie dogs, who apparently love M&Ms. By vaccinating the black-footed ferrets’ prey, scientists should be able to prevent the disease from spreading to more of the animals. As a bonus, the dye from the candy coating shows up in the prairie dogs’ whiskers, which will make it easy to gauge how much they’re actually eating the candies and taking to this novel vaccine delivery method.

Once the Fish and Wildlife Service approves the plan, it should go into effect by September 2016 and will start at the UL Bend National Wildlife Refuge in Montana. If successful, it will be implemented in Arizona and Colorado as well.

Drones will make the process quick, simple and cheap. They expect to be able to cover tens of thousands of acres of prairie dog and black-footed ferret habitats each year, which would take far more time using other distribution methods.