Outdoors_lol_08-13

Jeff Green | Apr 03, 2008

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Winter is releasing its icy grip on the Land o’ Lakes very slowly this year. As I write this column, snow is piled about more than three feet deep all around my house and in the woods and the ice on the lakes still seems pretty thick. Originally, I had planned this column to be on early spring wildflowers, but it will have to wait for a couple of weeks. In the past I have seen a few hardy hepatica flowers as early as the first week of April in south-facing sheltered areas, but I don’t expect this to be the case this spring. While hepaticas may be very hardy, even they need at least a bit of heat before they bloom – and heat has been in noticeably short supply this spring!

Instead, I thought I would write about one of the very common but tiny creatures that we occasionally encounter in winter – snow fleas. On a warm, sunny winter day, take a look at the base of a tree where the snow may have melted to uncover some of last year’s leaves, or where the snow has been hollowed out by a footprint. If you see a sprinkling of what looks like ground pepper on the surface of the snow, have a closer look – if the bits of pepper are moving, it is likely that you have discovered snow fleas.

I have been fascinated by these tiny snow hoppers since I was a young boy. What are they? What are they doing out in winter? How can they survive on snow?

In fact, snow fleas are not fleas at all – rather, they are members of a family of insect-like animals called springtails. At about 1-2 millimeters in length, they live in soil, in mosses or in leaf litter, where they make a living by eating decaying organic matter as well as bacteria, fungi, algae, pollen and other small soil creatures. In winter, snow fleas come out on warm, sunny days to feed on decayed plant material that has collected on the surface of the snow pack, or on sap oozing from the tree. Sometimes they are found near ponds or even on the surface of a pond; they can walk on water. Like other springtails, they lack wings but can catapult themselves in a random direction by releasing two tail-like "springs" hooked to the abdomen. Since snow fleas can't control their flight or direction, they frequently land in the same spot or only a few inches away.

Research at Queen's University in Kingston has discovered that snow fleas have an anti-freeze-like protein in their bodies that allows them to operate in sub-zero environments. They are hoping that this protein may prove to be useful for storing transplant organs for longer periods of time and for producing better ice cream by inhibiting ice crystal formation. Who would have thought that something this useful could be found by looking a little closer at a little black speck on the surface of the snow?