Insect population collapse and why it matters now

During childhood visits to my uncle’s farm, the chirping of grasshoppers filled the summer air "in the bee-loud glade", while the squashed remains of crane-flies beetles and moths dotted the car windscreen.

Nor were we starry-eyed lovers of the little creatures — horseflies and mosquitoes were out for our blood. Wasps stung and biting midges rendered heather moorland off-limits in late summer. Then came DDT and, like Maurya’s drowned sons in Riders to the Sea, "they are all gone now"!

Mother Hubbard’s insect cupboard may be bare these days, but those early avian visitors, the swallows and martins, are arriving from Africa just now. What a challenge they face! It is estimated that each one will consume around 60 insects per hour, 850 in a day, 25,000 every month. Keeping body and soul together is an increasingly ‘tall order’.

Irish insects don’t kill us, but that can’t be said of their tropical cousins. According to the World Health Organization, around 600,000 people died of malaria in 2023... three-quarters of them children under the age of five. This, the world’s most lethal disease, isn’t caused directly by insects but by a parasite carried by them. Female anopheles mosquitoes, Irish ones included, need a blood-meal to form their eggs. Flitting from person to person, they spread the disease.

Despite the huge size of their army, Nature’s six-legged soldiers are retreating everywhere. But they will win the war. Insects were here long before we humans arrived on the scene and, no doubt, will still be around long after we are gone.

Nobody knows how many kinds of insect there are. More than a million species have been ‘described’ to date, but entomologists think that up to 10 times as many have yet to be documented. There may be a billion insects for every person alive today.

We lament the extinction of the dodo, the woolly mammoth and the giant Irish deer, as indeed we should. But we seem to have a blind spot where creepy-crawlies are concerned. Out of sight, out of mind, little things get overlooked.

And so we continue our campaigns of brutal chemical warfare, sending these little creatures to the wall at an alarming rate. We don’t even know what species we are exterminating or what potential benefits to ourselves we might be losing.

But our misdeeds are returning to haunt us. The birds, whose singing we love so much, are disappearing. The dawn choruses of today are feeble compared to those of the past. Bird populations here and elsewhere have been halved during our lifetimes, with a 40% decline in the last decade alone.

Habitat destruction, climate change, domestic cats, mono-cultural planting, speeding cars, and the 'potty-training' of suburban parks and gardens, share the blame. Wilderness areas of weeds on which insects depend, are being removed in 'neat and tidy' measures. These create pretty, but sterile, conditions.

The decline in insect numbers must surely be a significant factor in the drop in bird numbers. Birds need protein-rich food for their young. Insects and their larvae are the great source of that.

Is our world dying?