MARCH
1997

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

03-13-97

Bugs Know When Spring Has Sprung

Everyone has their favorite indicator that spring has sprung. For some it's the peep of the peeper. This little frog begins singing early in the season and is appropriately called the spring peeper.

Other people turn an eye to the sky and note the flight of migratory waterfowl. Ducks and geese headed north indicate that winter may be winding down. A robin red breast hopping on the lawn in search of an earthworm indicates to some folks that the sound of lawn mowers cannot be far behind.

But sometimes peepers are quieted by a frozen pool, and migrating ducks and geese are forced to land because of a late winter snowstorm. Even the old robin has been seen chirping forlornly from an ice-encrusted branch.

Native Americans turned to the butterfly as a sure indicator of spring. In the southwestern part of the United States, the Zuni tribe held that "When the white butterfly comes, comes also the summer."

Butterflies specifically, and insects in general, aren't as likely as frogs and birds to make a mistake when predicting the end of winter conditions. Even the term butterfly shows how confident ancient people were about this insect when it came to the seasons. Butterfly is a short version of "fly of the butter season," or spring. This was because spring was when cattle traditionally gave birth and produced milk and cream, which was used to churn butter.

Insects are unable to function in temperatures below 50 F, so it is important for them to make sure summer is here before they are. In general, insects remain in hibernation until all chance of freezing temperatures is past. However, there are exceptions.

Some insects overwinter in protected places as adults. These insects are some of the first seen in the warm days of late winter or early spring. Such insects as ladybugs and some flies commonly come out of hibernation as temperatures rise and can be seen crawling or flying around our homes. Some of the first insects seen in the early spring are the large overwintering queens of bumble bees and wasps. These queens hide in protected places and emerge in late spring and early summer to begin a new colony.

There are even a couple of butterflies and several moths that overwinter as adults and can be seen flying around on the first warm days. In general, though, butterflies overwinter as pupae and don't show up until summer is safely here to stay.

So if you're trying to predict the end of winter, do as Native Americans have done for centuries. Ignore the birds and frogs, and put your money on the butterflies. After all, they are not called flies of the butter season because they have a habit of getting frost on their wings!

 

Writer: Tom Turpin
Editor: Andrea McCann