My Collins Concise Dictionary defines lek, the noun, as ‘a small area in which birds of certain species, notably the black grouse, gather for sexual display and courtship’, and the word can also be used as a verb, hence lekking, the activity of courtship display in that area.

The dictionary only mentions birds and, certainly, we usually think of lekking as something confined to birds, but the act of showing off in order to attract a mate is not confined to avian species; insects and, apparently, some fish, also perform mating displays.

And that’s exactly what these Green long-horn moths (Adela reaumurella) were doing when I spotted them congregating around a particular bush in an area of trees (in fact, I’ve now seen several such displays in various woodland or tree-filled locations). I’m not sure why they choose their particular spot but it seems to be a prominent position towards the top of a shrub or on a branch that sticks out from the rest of a tree, often in sunshine, and they flutter about, settle briefly on a leaf, then flutter again. The lek is a delight to watch.