Snow Fleas

If you have not seen them you would likely classify Snow Fleas in the same category as the Sasquatch and SideHill Gougers. But those who have seen thousands of tiny dark specks hopping about on the snow, know that Snow Fleas are real.

They are usually seen on winter days when the temperature is warmer than -4 degrees C. During these days, the Snow Fleas are moving about on the snow surface searching for something to eat — usually pollen or other windblown organic material.

Snow Fleas are not fleas in the true sense, but belong to an order of insects called Springtails. They are minute, wingless insects that normally move about by walking on the tips of their claws. However, when frightened they release· their springtail (an appendage that is bent forward under the body just in-front of the rear end) which catapults them forward. It is this hopping motion that gives them their common name - Snow flea.

Snow Fleas are not the only insects capable of surviving in cold weather. There are also Snow Spiders, Snow Scorpion-flies and Snow Crane Flies. They all demonstrate a remarkable biological phenomenon of remaining active in sub-zero temperatures. There is not a great deal known about how these cold-blooded insects manage this feat. However, Naturalist John Woods men­tions in his article One Step From Death “that the Snow Cranefly body fluids freeze slightly below zero enabling them to function in a supercooled state.” In other words they can move about when they should be frozen solid. John also states "we do know that supercooled animals are living on the edge of death. A sudden jolt, the knock from a branch, a whack from a falling clump of snow, can start a chain reaction crystallizing their body fluids and killing them in their tracks." Whether or not Snow Fleas operate with a similar an­tifreeze is not known. In any case, knowing that Snow Fleas do exist should make your next winter walk or cross-country ski trip more interesting.

Posted on February 11, 2022 03:17 AM by larryhalverson