Bug of the Month Meet the Snow Flea the tiniest little critter you never even knew was there….
The tiny black creatures you may have noticed crawling on top of the snow this time of year go by an unfortunate name: Snow Fleas.
These tiny insects, more properly called springtails, are the most plentiful creature in all of Ontario and are found everywhere on globe. It is important to note, not being a true flea, they have no interest in humans and no interest in your pets. Springtails are unique in that they have a stiff, hinged appendage that tucks under their abdomen and when they feel threatened, they unlock this tail piece which flips down with such force that it flips the critter up, up and away for quite a distance.
Back to the name ‘snow fleas’ for a moment: no, they do not bite people or dogs or birds. They eat only vegetation and never live on another creature. Parasitic fleas and lice are also small, and ‘way back when’ somebody thought the little springtails looked suspiciously like a cat’s flea
Snow fleas are so small that 40 of them would easily fit on a person’s thumbnail.
Their population is very challenging to estimate, however someone has figured out that there are about 25,000 of these guys and gals in each square yard of soil (most common in undisturbed areas like forests but absent from places where pesticides are applied). Not only are there a lot of them, but they are everywhere, and that is speaking globally. From the Antarctic to the Arctic, snow fleas are found just about everywhere.
Not only are they numerous, but their role in nature is perhaps one of the most critical of any species on Earth. They live in the soil where the air spaces between the dirt particles are big enough to accommodate them. Here they feed on organic litter, perhaps better known as ‘dead leaves.’
When a dead leaf falls to the ground, it will eventually decay and become soil again. That process would not happen as efficiently as it does without the help of the springtails. The fallen leaf is swarmed by these insects which chew it into itty-bitty teeny-weeny chunks, thus allowing the fungus and bacteria to go to work and release the nutrients and create humus soil. Without the springtails, the leaf would just lay there, decomposing but very, very slowly.
Despite their importance and abundance, little is known about springtails
While snow fleas can be found across North America in all seasons, they tend to be most noticeable in the late winter when they climb up from the dirt in the direction of the sun.
Their bodies contain anti-freeze. Their nickname comes from their ability to withstand temperatures as low as zero degrees, a feat made possible by a powerful biochemical ‘antifreeze’ that is coursing through their tiny bodies.
Appearance: A primitive insect, the snow flea (Hypogastrura nivicola) is a very small, about 1/10 of an inch long and dark blue-gray. They have a somewhat plump body and have small compound eyes comprised of only eight facets in each. Snow fleas are wingless but can jump
How do they jump? A type of springtail, snow fleas can jump by using a forked appendage held under their abdomen called a furcula. Facing forward, this furcula is held in place by a clasp like structure known as a retinaculum. When the furcula is released, it propels the snow flea up and forward. A snow flea can jump up to several inches.
Where and when do you find them? Snow fleas live in the soil and leaf litter where they eat microscopic fungi, algae, and decaying organic matter. Even though they are very abundant, they go unnoticed during the summer.
However, snow fleas have a higher tolerance for colder temperatures compared to typical insects; as the snow starts to melt in late winter, they can move up through breaks in the snow. You can find them on top of the snow in potentially large numbers, at times literally turning snow black. Watch for snow fleas especially around the base of trees.
Also of interest is that a snow flea has no ‘tailpipe’, that its excrement is shed with its old exoskeleton during molting… However, realize that this anatomical feature is a point of disagreement between some biologists. One thing biologist’s do agree on, is their sex life. The “how” the females become fertilized is of real interest, as the males and females never have to meet each other. The males deposit sacs of spermatozoa throughout the area, and the females pick up the sacs and become fertilized, never knowing exactly who the father might be.
In just nine weeks’ time the eggs have hatched and the kids are producing offspring of their own. This does keep the population very high, a crucial requirement to ensure that new soil is constantly being produced.
All it takes is a sunny day to lure these critters topside of the snow, sometimes even in the middle of winter. When snow fleas sense things are beginning to thaw, they move from their mud-bound home to feed on algae on the snow surface.
This insect also likes a party: Sometimes on the surface of the snow they form huge colonies, as wide as a yard, with millions of individuals migrating together like a superorganism, devouring the algae that grows on wet, decomposing leaf litter in the melting snow
Fun Facts: Researchers at Queen’s University in Canada have examined the anti-freeze protein that allows snow fleas to be active at colder temperatures. They believe that by better understanding these proteins, similar ones can be created to better store transplant organs and make better ice cream!
Like most Canadians snow fleas are attracted to maple syrup, sometimes they can be found in buckets of sap when it is being harvested.
Here is a link to a quick video that shows the snow flea in action.
