Sometimes in the spring, it can look like someone has scattered large amounts of ground black pepper across the snow. But if you zero in one area, you will soon see that these flakes do not just lie there.

The little black specks will jump like crazy if you get close, which is why some people call them snowfleas. But their other common name -- springtails -- more aptly describes them, for these tiny wingless critters have a secret weapon for moving out of harm's way.

"There are all kinds of ways of jumping around, but the springtails have a unique one," says Jim Kruse, a curator at the University of Alaska Museum in Fairbanks.

A forked structure called a furcula is attached to their underbellies, held in place by two hooks. When its time for action, they release the hooks, snap their furcula down and launch themselves through the air.

The northern variety of springtails are about two-mm long, but they can propel themselves as much as 100 millimetres through the air -- a distance 50 times their own body length!

In the world of track and field, this would be comparable to a six-foot human covering more than 90 metres, or 300 feet, in the long jump event. (For the sake of comparison, the Olympic record for this event stands at 29 feet two and a half inches.)

Fortunately for the springtails, they do not have to move around too much. These scavengers spend most of their time rooting around in the leaf litter, munching on decaying vegetation and soil fungi. They are part of the community of decomposers that break down and recycle organic wastes.

Springtails can be found almost anywhere in the world, from the canopies in tropical rain forests, to the deserts of Australia and the frozen wastes on Antarctica. In the North they are more obvious at this time of the year because their dark colour shows up well against the snowpack. On sunny days, they congregate in great numbers on the surface of the snow to feed on microscopic algae, bacteria, and fungi and to complete mating.

"In their life cycle it might be advantageous for their breeding to get hold of certain foods. They get out early and do well on what is available on the snowpack," says Kruse.

Springtails belong to a very primitive group of invertebrates named Collembola, a name that refers to yet another unique structure on the underbellies of these tiny bugs.

The exact function of the tune-like collaphore is not known, but it probably helps springtails absorb moisture from the environment, preventing them from drying out.

You can find springtails year-round if you know where to look. Kruse suggests hunting for them in damp places such as along riverbanks. To collect them, take a pan of water and brush it slowly through the grass. Springtails and other assorted small critters will fall into the pan.

But you will need a high-powered microscope to see many particulars on them. Springtails are so small that molecular techniques were needed to sort out their taxonomy. They are classified as a type of arthropod, which are invertebrates with segmented bodies and jointed limbs.

But unlike most arthropods, springtails appear to have evolved in cool climates, and can survive the frigid temperatures found in the North. Overall, we know very little about these critters as they are not a major agricultural pest and have not merited much research attention.

But the next time you are walking across the snow and notice a film of black dots on the surface, remember that we do know this: the "spring" in springtails stands for the way they move, not the season when we usually see them.

For more information, a number of websites have good information on springtails. Try http://www.cals.ncsu.edu/course/ent425/compendium/collem.html.