March 20, 2013 —
There are some insects that just don’t know when to quit, it seems. On a mild day in winter, you may spot small flying insects, spiders, or even the striking Mourning Cloak butterfly. These insects are protected by antifreeze-like substances in their bodies, and it doesn’t take too much mild weather to see them emerge for a temporary hiatus from their deep winter dormancy.
Some favorites to see on a March day, if there is still snow on the ground, are springtails, or snow fleas. Found around areas of leaf litter year round, they are easily seen in the winter when they appear on top of the snow. In some cases, these 1/16-inch-long snow fleas carpet snow cover by the thousands, making the snow appear dirty or pepper covered.
Springtails do not appear very mobile, with their short legs and wingless bodies, but when they want to move springtails live up to their name. Two appendages under their abdomen (furcula) can flick the springtail up to several inches away. They look like fleas when they seemingly instantly disappear, but they share none of a flea’s bad habits such as biting you or your pet. Springtails are beneficial as they feed on leaf litter and convert it to soil.
In 2005, scientists from Queens University in Canada studied the “antifreeze” protein present in springtails; the aim of this research was to isolate a compound that could be used to enable storing human transplant organs at a lower temperature, thus increasing their preservation time.
You may see some additional snow cover interspersed with mild days from March into April, making it an ideal time to spot some snow-fleas on snow near gardens or forest habitats.