Ht ere's another collection technique to find insects that are underfoot.


Large rocks, rotting logs, or boards (outside) Crayon Plain paper

Some insects spend most of their lives just out of sight. Carefully roll over large rocks, boards, and rotting logs to look for crickets, carpenter ants, bark beetles, wood roaches, termites, crickets, and their arthropod cousins, the millipedes, centipedes, and pillbugs.

In addition to finding insects, you might notice tunnels under

Make a Connection

If you want to eat insects on purpose, get some recipes that use insects at www.ent.iastate.edu/misc/ insectsasfood.html.

flh M
Troll Kolorowanka

White Light the bark on a rotting log. These are created by bark beetles, with each type of beetle creating a unique tunnel pattern. Some entomologists can tell which beetles are around just by looking at the tunnels.To save these patterns in your journal, peel the paper wrapping off of a crayon. Place a piece of plain paper over the bark beetle tunnel, then rub the long, flat side of the crayon over the paper. The tunnels will appear as a lighter area on your colored paper, preserving evidence of your insect finds.

Carefully put the rocks, boards, and logs back in their original positions before you leave the area.

Mo oths, stag beetles, caddis-flies, and other insects that are active at night often use their sense of smell to find their food. Mix up a batch of bug bait to use on a warm summer night, and you will see insects that might otherwise escape your notice.

Walking on Water


1 cup (240 ml) fruit juice Large bowl with lid Spoon

2 very ripe bananas >4 cup (59 ml) sugar, honey, or molasses Paintbrush Flashlight Sweep net Looking jar

Leave the fruit juice on your kitchen counter in a covered bowl. After two days, open the lid and use the spoon to mash the two very ripe bananas into the juice. Stir in the sugar, honey, or molasses. Since this recipe can attract a lot of insects, ask an adult which tree, fence post, or utility pole near your house would be the best place to paint the bug bait. Go outside before dark and use the paintbrush to paint the mixture on the chosen site.Wash the brush thoroughly so you can use it later to catch some of the insects. About an hour after dark, use a flashlight to check and see if any night prowling insects have found your sugar stash.You can use your sweep net to catch the flying ones, and the paintbrush to gently brush the crawling insects into your looking jar.

Real Entomologists t At

\l\ hile they are out looking 1/ \ for food, a mate, or trying " " to avoid bats,June bugs, luna moths, mayflies, and many other insects get together around lights at night.You can use this to your advantage as a way to catch even more insects.


String, rope, or clothesline White sheet

Light source (porch light, flash-

Journal Notes

I put , paper clips into the full glass of water.

When I put the paper strider on top of the water, this is what happened:

This is how long the water strider floated on top of the water:

Water molecules like to stick close to each other, showing a force called cohesion (co-HE-shun). Where the water molecules meet the air, their

Real Entomologists cohesion creates surface tension. This surface tension creates a thin skin on the water. This skin on the water is strong enough to support lightweight objects.

Animals that walk on water spread their weight over a large area so they won't break through the water's skin. Your paper strider should have remained on top until water soaked through its feet, causing it to become heavier and sink.

For a long time, scientists have known how water boatmen, backswimmers, and whirligig beetles use their oarlike legs to move across the water. What they didn't know was how the long-legged water strider, which walks on top of the water, moves forward. Two graduate students from the Massachusetts Institute of Technology decided to find out. After carefully studying water striders in action, it appeared to them that the striders were using their front and back legs for support, and their middle legs as oars. To test their theory, they created a robotic water strider using a 7-Up can, stainless steel wire legs, and a rubber band-powered pulley. They put the robot in dyed water and filmed the result. Sure enough, when the middle legs hit the water, they create tiny vortices (like miniature, underwater tornadoes) that move the water strider forward.

Water We Icking for?

light, lantern) Newspaper Looking jar

On a calm evening, string a rope between two trees or use a clothesline. Hang the white sheet over the rope or line. Turn on a light, lantern, or flashlight on one side of the sheet. Come back about two hours later to see how many different insects have landed on the sheet to be near the light. Place newspaper under the sheet and gently tap the sheet, making some of the insects fall onto the paper below. If you work quickly, you can tilt the paper and slide the insects into your looking jar so you can get a closer look.

Water World

If you only look on land, you will miss seeing some very special insects. Aquatic insects have developed amazing adaptations to help them survive.Whirligig beetles have two pairs of eyes so they can see both above and below water at the same time. Diving beetles are scuba divers, rising to the surface to get a bubble of air under their shells so they can stay underwater longer. Dragonfly nymphs jet through the water by releasing a powerful squirt of water through their abdomens. And don't forget to take a second look at those skinny sticks moving across the top of the pond to see if they are really water striders walking on top of the water.

Visit a pond throughout the year to catch an amazing variety of aquatic insects.

Visit a pond throughout the year to catch an amazing variety of aquatic insects.

mayfly nymph

I I ow do water striders and I I fishing spiders move across A X the top of the water without falling in? The shape of the animal and the attraction of water molecules to each other both play a part in keeping water walkers from getting wet feet.


Thin writing paper



Large-mouthed clear cup Plate or pie pan Water

Box of paper clips Watch

Lay the piece of paper over

Compound Eyes

mayfly nymph the pattern of the water strider, trace the pattern onto the paper with your pencil, and cut the pattern out. Bend the feet along the lines so the strider can stand up, and put it to one side. Place the clear cup on the plate or pie pan and fill it up to the very top with water. Count how many paper clips you can carefully slip into the water one at a time, making sure your fingers don't touch the water. Once the water is higher than the rim of the cup, carefully place the paper strider onto the water and use the watch to record how long it stays on top.

mayfly nymph

Make a Connection

To see examples of aquatic creatures and learn how tolerant they are of pollution, go to www.iowater.net/ Benthickey.htm.

JntgectigationgI Qame B°

I nless you plan on submerg-I I ing yourself in a pond to see Vy insects that have amazing aquatic adaptations, you'll have to catch the insects instead.While water striders and whirligigs are easy to find on the surface of a pond or stream, dragonfly nymphs, diving beetles, and many other insects hide under rocks, in the mud, or on the plants underwater.


Kitchen strainer with screen bottom

Small-screened aquarium net Clear cup

Shallow dish with a white bottom Magnifying lens

You can wait until you see an aquatic insect, then make a big splash trying to catch it, or, like the sweep net, you can catch a large number and variety of insects by simply scooping through the water with the strainer or net.Visit a shallow pond or stream in your area. (Check with an adult first.) Pull the net across the top of the water, then past plants, and through the mud. If you get too much mud, use the cup to pour pond water through the net. After most of the mud is gone, see which insects you have caught. If you are looking in a stream, pick some rocks from the stream bottom and see if anything is hanging on to them.To get a better look, put the insects and some water in the white-bottomed dish and use your magnifying lens. Since water is a natural magnifier, you can also fill your clear cup with water and insects and watch them in action. Of course, you might also see some non-insect creatures including tadpoles, shrimp-like scuds, leeches, worms, crayfish, and spiders, too.

Clean Water Monitors

Next to air, water is probably the most essential item for living things. People need clean (not polluted) water for drinking, cleaning, cooking, playing, fishing, growing foods, and many other activities. One way water experts determine the quality of water in a stream is by looking for aquatic nymphs and larvae of insects.The rule of thumb is that the less polluted the water is, the greater the variety and number of species you will find in it.

As a quick way to determine the quality of stream water, monitors can look for immature insects that are very sensitive to pollution.They go to where the water is moving fast and find three hand-sized rocks that are not buried under mud or other rocks. They pick up the rocks and turn them over, looking for stonefy nymphs, mayfly nymphs, and caddisfy larvae. If they find all three types of immature insects, they rate the water quality as excellent. This water is suited for all human uses. If they find mayflies and caddisflies, but

no stoneflies, then the water quality is considered good. If they find only caddisflies, then the water quality is rated as fair. If they don't find any of the three types of immature insects, the water quality is listed as poor.

Was this article helpful?

0 0

Post a comment