Snow Fleas: The Bugs That Make Their Own Antifreeze

Snow fleas, more commonly known as springtails, are not actually fleas at all. They don’t bite or sting; instead, their name refers to the fact that they are commonly seen on top of snowbanks, and to their impressive leaping skills. They don’t cause any structural or material damage, they won’t bother your dog and, though common, snow fleas are rarely seen by humans at all. So, why should you care about snow fleas?

Besides their mighty bounce, snow fleas have some unique talents that allow them to live long after most insects have been wiped out by freezing winter weather. Whereas most insects perish as soon as it gets cold, snow fleas can be found thriving in temperatures far below the survival limit of your average bug – so, what’s their secret?

What are snow fleas?

Snow fleas are tiny insects with no wings and a humpbacked appearance. They have a forked, tail-like structure on the rear underside of their abdomen which they can use to catapult themselves up into the air (hence their other common name – springtail). This “leaping” behavior, along with their minuscule size, gives them the appearance of fleas but, unlike true fleas, they don’t bite.

Snow fleas love moisture and are thought to eat decaying organic matter. As a result, they usually found in damp soil, leaf mold, under bark, in compost heaps and in decaying logs. Though very common, and often present in large numbers, their small size and preferred habitat means they are rarely seen.

Occasionally, large numbers of snow fleas will appear on top of snowbanks, where they feed on fungal spores and algae on the surface of the snow. Snow fleas are usually black in color so, when this happens, they will stand out vividly and can be seen clearly against the snow.

snow fleas on snow


Why are they called “snow fleas?”

Snow fleas don’t bite, and you won’t find them in your dog or cat’s coat. Instead, they get their name from their mighty jump, and from the fact that they are most commonly seen on snowbanks.

Though present year-round, snow fleas usually hang out in soil and decaying leaf mold, where their dark color and small size keeps them hidden from human eyes. Therefore, they are usually only seen when the weather gets cold and they gather to feed on the fungal spores and algae found on the surface of the snow.

How do snow fleas survive through the winter?

Unlike most insects, snow fleas are found year-round and can thrive even in the depths of winter. Scientists have discovered that this special ability is all thanks to a glycine-rich antifreeze protein, which is found throughout their bodies and effectively stops them from freezing to death.

Most insects are cold-blooded, meaning that, like reptiles, they rely on external sources of heat to survive. When winter rolls around and their environment gets too cold, their bodily fluids freeze, their cells rupture and they quickly die out (until the following spring, anyway).

The snow flea, however, has found a way around this.

When temperatures freeze, their antifreeze proteins bind to the surface of ice crystals as soon as they begin to form and prevent them from growing any bigger. By doing so, the antifreeze protein successfully stops the snow flea from freezing solid.

Do snow fleas bite? Can my dog get snow fleas?

They may bounce but, unlike regular fleas, snow fleas don’t bite or sting. This means you won’t see snow fleas on your dogs, and they won’t bite your ankles if you walk through a patch of them, either.

In fact, snow fleas rarely pose s problem and snow flea treatment is usually unnecessary even if they’re in your yard. However, snow fleas can become a nuisance if they manage to get inside your house.

Though most often found outdoors, snow fleas may invade damp areas of your home (such as the basement, kitchen or bathroom). They won’t cause any structural or material damage, but they can multiply quickly and gather in large numbers if conditions are suitable.

How can you stop snow fleas from coming into your house?

Snow fleas are rarely a problem but, if you are frequently bothered by home-invasions from these tiny, bouncing bugs, the key to controlling them is to eliminate their water sources. Snow fleas are highly dependent on moisture for their survival, so drying out damp spots will make your house less appealing to them.

Clear up any standing water around your house and check for possible hidden sources, including blocked drains, AC units, and leaky faucets. If particular parts of your house are especially damp (a common problem in confined areas, like the basement), install a dehumidifier and take measures to improve ventilation.

Pro tip!

Snow fleas are especially fond of moist soil, so check your yard for water leaks, especially around the foundations of your house. Do what you can to dry out your yard, or to direct any water flow away from buildings.


Snow fleas (aka springtails) are almost always seen leaping around on the top of snowbanks in the winter, where they feast on fungal spores and algae. Despite their name and bouncy behavior, snow fleas are not ‘true fleas’ and don’t bite or sting. In fact, they are rarely even seen by people due to their tiny size and their usual habitat of soil and leaf litter.

What’s remarkable about their snow fleas is their ability to survive through winter, when most insects naturally perish in the low temperatures. This is thanks to their ability to produce an antifreeze protein that stops ice crystals from forming in their bodily fluids and effectively prevents them from freezing to death.

Snow fleas are harmless and are rarely a problem, though they can be a nuisance if they get inside your house and multiply. To prevent this from happening, eliminate damp around your home – snow fleas need a continuous supply of moisture, and won’t thrive indoors without it!

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