In the northeast, we have an old habit of giving plants, fungi and animals misleading names. Poison ivy is actually in the sumac family, Spanish moss is really a lichen and nighthawks are only distantly related to hawks (and are active at dawn and dusk – not at night). In many cases these names make a plant or animal sound tougher than it really is – a bit of naturalist false-advertising. My favorite example of this false-advertising is the widespread use of flea in naming small animals.
If you look closely at a damp section of beach, you may notice tiny hopping insects, each barely larger than a grain of sand. These are sometimes called sand fleas. They are not to be confused with sand flies, also called no-see-ums, which are among my least favorite animals. If you boat or fish, you know why.
Like most animals, sand fleas have been given many names, including snow fleas and springtails. Because they are neither restricted to sand nor snow, I will refer to them as springtails from here on.
As you might suspect by now, springtails are not actually fleas. Springtails are closely related to insects, but reside in their own unique class, called collembola. They are typically black to dark blue or brown, which is why they are most commonly noticed on clean snow or light-colored beaches. Springtails rarely surpass 1/8 of an inch in length. They have two special hind legs that bend under their body, which they can use to launch themselves several inches at a time – hence the name springtail.
Springtails live and breed in most moist soils. Adults emerge from thawed soil in early spring to forage. If there is still snow on the ground, springtails may end up climbing to the top of the snow, where they are very easy to see. They may look like dark stains or fungi on top of snow or around the bases of trees, but close inspection will reveal a mat of thousands of tiny, hopping critters. Their tiny weight and hairy legs also allow springtails to aggregate on the surface of puddles and tide pools. Aggregations of springtails are usually for one of two purposes: feeding or mating.
Springtails live at very high densities in the upper layers of forest soil and leaf litter. If you were to take a small trowel into the woods and scoop up a cup of soil, then dry, stain, sieve, and sort the soil, you would have too much time on your hands. But you would also have thousands of adult springtails. Springtails thrive in damp areas, so you may find them in damp beaches, near ponds, in fields, and all over the forest. You may even find them in houseplant soil, where they pose little risk to you or your home. So far this summer I have found springtails on Sandy Point Beach (Stockton Springs) and Wolfe’s Neck (Freeport).
Springtails are omnivores, eating fungi, pollen, algae, bacteria, and dead organic matter. They provide food for a variety of forest critters, including ants, mites, beetles, centipedes, and even salamanders. Because they exist in such high densities (albeit seldom seen by humans), springtails provide an important connecting link in Maine’s food chain – moving energy and nutrients from plants to the insects and amphibians that feed our numerous hungry birds.
Despite their flea-like appearance and nicknames, springtails never bite people or animals (they lack the mouthparts necessary to do so). While they may aggregate around homes in damp times during the spring, springtails will not cause an infestation like ants or termites. For all its infamous nicknames, a springtail may be the most benign beach animal you could meet.