Field Observations

You can insect-watch much as you might bird-watch — by going into the field and keeping your eyes and ears open. A binocular is seldom needed, as for bird-watching, except occasionally for such insects as dragonflies. A hand lens, however, is very helpful.

A pond is an excellent place for watching insects, it probably has water striders and whirligig beetles moving about on its surface, various beetles, bugs, and other insects in shallow water where they can be watched from shore, and dragonflies, damsel-flies, and other insects flying or resting near or over the pond. Brief observation of the dragonflies, for example, will reveal that each species has a definite zone (height) of flight above the water surface, each flies and rests in a characteristic manner, and each has a particular method of laying eggs, flying in tandem, and chasing other individuals. An observer will discover that some of the larger dragonflies patrol definite territories; they will attempt to mate with any female of their species entering this territory, and will engage in characteristic dances or chases with other males of their species that enter the territory. An examination of the vegetation around the edge of a pond may reveal nymphs transforming into adults. This process — the adult emerging from the nymphal skin and expanding — takes from one-half hour to an hour, and at the right season it is not difficult to find emerging individuals.

Another good place to watch insects is at flowers. Many insects occur there, and although some of them are fairly small they can usually be observed at close range. Observation of the bees will reveal the basis of the expression "busy as a bee"; a butterfly may be seen uncoiling its proboscis and extending it down into the flower; and the sunlight striking the wings of a hovering syrphid fly will make it look like a small jewel. Some animals occurring on flowers are predators, and feed not on the flower but on the bees and flies that visit it. If you observe a flower containing a crab spider or an ambush bug for a while, you might see either animal catch its prey, and you will be surprised at how large an insect it can catch. The observant insect-watcher will see many instances of one animal eating another.

Ants are very interesting insects, especially at or near their nest, or on plants in association with aphids. The ground around a large mound nest may be almost alive with ants coming or going, perhaps carrying something. If a stone or board is lifted and an ant nest under it is exposed, the ants will busily transport their young to the shelter of their underground burrows. A few ants are often found around a large cluster of aphids on a plant; if you observe these for a time you may see the ants feeding on a watery fluid (honeydew) that issues from the end of the aphid's abdomen.

A plant selected at random and examined carefully will seldom fail to have some insects on it, and there are likely to be many kinds — each on a particular part of the plant and behaving in a characteristic fashion. The plant may also contain the eggs, larvae, or pupae of many types of insects.

If you visit a site at fairly regular intervals you may be able to follow the seasonal history and development of the insects there. The development of a wasp nest, galls, leaf miners, the activities of a group of webworms or tent caterpillars, or the development of the insects in a fallen log can be followed by such observations.

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