Second Nature Pepper on Snow By Bonnyvale Environmental Education Center
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an you imagine a creature so small that you could easily mistake it for a speck of pepper and yet so abundant that it is one of the most common land creatures in the world? This same organism is so ancient that scientists have just recently come to understand that it is not truly an insect. Insect, or not – it is more plentiful than ants! Have you guessed it yet? The answer is a snow lea, or Hypogastrura nivicola, a type of springtail. All springtails are really tiny, wingless and only a couple millimeters long, less than 1/10 of an inch. Due to their incredibly small size, you will do best to take along a small person with you when you go in search of them, as children have a knack for seeing details that all too often elude adults. Besides their small size, something else that makes a springtail a springtail is their mode of transportation. Because they have no wings they use their “tail,” which isn’t really a tail at all. It is actually a pair of stif prongs, which are held against their bellies by tiny hooks. When the hooks open, the prongs spring out, catapulting the critter into the air. They can land as far as 100 body lengths away. Impressive! But do remember that is 100 body lengths of a snow lea… At left, a snow flea is greatly enlarged (actual size approximately 1/16 inch) and, right, snow fleas seen at the base of a tree. Drawings courtesy Cornell University, www2. entomology. cornell.edu.
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Snow leas are one kind of springtail that you stand a good chance of inding with your family, particularly during a February thaw. They are called snow leas because they are active in the winter and can easily be seen against the backdrop of a white blanket of snow. And, they jump like leas. But remember they are springtails, not leas. While springtails come in many colors, the snow lea is grey to black. With all this information tucked neatly into our wool hats, it is time to head out for an adventure. Choose a warm (above 32 degrees Fahrenheit) sunny day in March. Pack up a magnifying lens or two, if you have them. Take a toddler (or older) in hand, and head into the woods. Since snow leas are forest dwellers, they are usually wellcamoulaged in the leaf litter of the forest loor, where they ind their food of dead plant matter and microscopic animals. But like many of us, they seem to crave the early warmth and extra light of a near spring day, emerging en mass in numbers as high as one million. The groups tend to stay concentrated in a round mass as they move. While some are hopping along on the surface of the snow, others are crawling along beneath the leaf litter of the forest loor. Keep your eyes open for patches of snow that look dirty, or if you will, as if they have been generously sprinkled with pepper. The fact that snow leas travel in such large groups and do not appear to be in a hurry (they can take several days to complete their 25-meter migration) is what makes inding them possible. If you see what appears to be a peppered patch of snow – perhaps at the base of a tree or woody stem where the snow has started to melt, or across some cross-country ski tracks, look closely! Try putting your hand in among the lecks. If they seem to disappear and reappear before your eyes then they are snow leas hopping like crazy. Get out your magnifying lenses, get down low and get a good look at one of the world’s most abundant critters – despite the fact that they are not seen or heard by many people in a lifetime! Second Nature is contributed by the naturalists at Bonnyvale Environmental Education Center. For more information, visit www.beec.org or call 802-257-5785
parentexpress • March 2017
