Watch out for that oil slick – it could be alive

EGLE’s Pollution Emergency Alert System got a call recently about an oil spill near Grayling. Investigators checked it out and found that not only was it not oil, it wasn’t pollution at all. Instead, it was group of tiny bugs looking for a meal in the snowbanks. They’re commonly known as “snow fleas” although they’re more closely related to shrimp.

A swarm of snow fleas on melting snow gather in numbers large enough to resemble an oil spill. 

The species’ scientific name is Hypogastrura nivicola. It’s a type of springtail, which is part of the arthropod family. Most are just a couple millimeters long, making it tough for people to see them. Snow fleas are the exception and it’s because they’re built to go scavenging during a cold Michigan winter.

Snow fleas can handle the cold thanks to a protein their bodies produce that acts like antifreeze, preventing the formation of ice crystals inside them. When the snow starts to melt, they rise to the surface to search for food. In large numbers their dark bodies can look like oil up against the white snow.

The name “snow fleas” comes not only from their resemblance to the biting pests, but also because they can leap relatively large distances. Whereas fleas use their powerful legs, snow fleas and other springtails use a small, forked tail to launch themselves to safety when confronted by a predator.

While the concept of leaping bands of tiny bugs in numbers great enough to resemble an oil spill may sound horrifying… it’s really not. In fact, the presence of snow fleas is a good thing for your yard.

“They don’t bite and they do a great job of eating decomposing leaves and other organic matter, especially near trees,” said Jeff Proctor, with EGLE’s Brownfield Section. “This results in nutrient recycling and fertile soil. They can also eat fungi known to cause diseases in plants.”

Snow fleas on a fingertip. 

The best part: they’re not interested in getting into your home. It’s way too dry indoors unless you have a damp basement. On rare occasions they’ve been found in kitchens and bathrooms, usually if there’s a leaky pipe. If that happens, fixing the leak and running a dehumidifier will usually send them running for the nearest snowbank, where they’ll inevitably trick someone else into thinking there’s been an oil spill.