Nature Articles - Bugs Galore!                                       

Bugs Galore!
By Suzanne Roth, Naturalist

It’s not quite twilight on a late summer stroll as the breeze dies down to almost a standstill. As you approach a nearby pond, you become enveloped with the sounds of the season: the deep, resonating bullfrog, clicking cricket frogs and the liquid trill from a red-winged blackbird.

Suddenly, a familiar high-pitch whine becomes louder and then stops. Before you can slap away the loathsome pest, a mosquito lifts off your arm, taking with it a touch of your blood and leaving behind an annoying itch.

The female mosquito uses warm-blooded animals, including people of course, as a source of nourishment. She needs a blood meal in order to produce eggs. She uses not one, but six needlelike devices to get what she needs: four to break the skin and two that serve as a pump. In order to suppress our natural blood-clotting process, she adds a chemical to maintain the flow. We itch because our bodies reject this anti-coagulant.

Your irritation is interrupted as a large insect, flying fast and changing directions, comes into view - a dragonfly! Suddenly its forward-pointed, dangling legs scoops a mosquito in mid-flight, securing the hapless insect with its gripping hairs. No sir, these legs aren’t made for walking.

Dragonflies are equipped to be some of the fastest, most agile flying insects on earth. This thick-bodied insect has four wings, each connected to its own wing muscle so that it can be controlled individually. This allows such acrobatic stunts as backward, vertical and even sideways flight. When not catching gnats and mosquitoes “on the wing,” dragonflies rest, perched with their wings held horizontally. Their fellow odonates (the insect order to which these flexible flyers belong), the damselflies, are smaller, thinner and rest with their wings held behind them. Both have two types of eyes that increase their odds of survival in this fast-paced life-style. Three very small eyes, called the ocelli, help them distinguish between light and dark. The second type are called oculi and are made of up to 30,000 facets, allowing a 360-degree field of vision.

You step closer to this seemingly death-defying stunt flier to figure out just where it keeps all these eyes when a piece of vegetation just grabbed your mosquito-devouring ally. Upon closer inspection, you find the creature that just outwitted the dragonfly used a clever combination of camouflage and speed – it’s a praying mantis.

The mantid doesn’t boast fast flight but has a subdued way of life. It is able to change color to match the background in which it quietly lies waiting. Effortlessly it plucks passing, unsuspecting prey out of the air or off a leaf. Spiny forelegs are used for holding the prey tight in its grasp while the head, capable of rotating 180 degrees, moves in for the fatal bite.

This voracious appetite begins as soon as the tiny nymph emerges from the egg case in late spring. Usually its first meal is a sibling. Family ties don’t grow any stronger as the insect reaches adulthood, for many are familiar with the female’s peculiar mating behavior. Later when she dines with a mate she will devour his head. Not out of malice but because his genetic material will not otherwise be passed on. Afterwards, she consumes the rest of him too. Neither one is designed to survive the winter so he begins preparing for the next generation.

The female praying mantis produces hundreds of eggs inside an egg case by secreting a protective substance that is whipped with air by appendages in her abdomen. The end result resembles a small piece of paper mache. She may go on to place more than 15 egg cases on dying fall vegetation. With her all-important task complete, she weakens and dies. Her eggs will overwinter in this protective case and by late spring, the cycle will begin again.

As you head back home from your short hike, you think about the complexities of the world just outside your back door. You just observed a few tiny links in an elaborate food web.