Re: Why do insects hover above trees in the evening

Hi Leow,

The main reason most insects will use tall trees is to do with warmth. They treat it like a cliff face, which has thermals for birds to use, as you probably know. The heat doesn’t come from the tree, as the ground is just as hot. All of the environmental heat rises for physical reasons and tends to creep upward by a tall object. Insects of course like to gather a a single point somewhere for mating. Groups of male midges often do this in your garden or by a pool.

You are dead right about trees giving out heat at night. Being often dark, they tend to give out heat more quickly than lighter objects in the early part of the night. You must realise that a large rock would do the same though. The last thing to remember is that by insects, you may refer to a butterfly or sawfly that lays eggs on the trees' leaves. Other trees might provide nectar or other food from flowers. Insects form most of the animals in a woodland, so the flying species would be found near a foodplant or the place where they hatched.

Finally, please consider whether the animal you are observing is part of a group (maybe even social) or one of several individual creatures that are using your tree. This determines exactly where it might hover or fly and thermals can indeed influence the social ant swarms, as they mate in mid-air. Single insects will be probably looking for a place to hide from bats or birds and close their wings for the night. Trees have something very special in which they can camouflage themselves - they are called leaves! If you look at the pictures of moth and butterfly “underwings” in a butterfly book, you will see what I mean. Perhaps the Comma butterfly is one good example.

Trust I have this back to you in time, Leow. Hear from you again soon!