Country Matters: Tiny but brilliant creatures are better than pesticides

Ants are incredible, hard-working creatures

Joe Kennedy

August 28 2022 02:30 AM

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Patiently I have watched ants for lengthy periods at their agricultural practices, endlessly busy cutting and ferrying vegetation to maintain the farms producing their fungal livelihood. Leaning over cliff top fences on Portugal’s Atlantic coast, I have looked at endless processions of insects moving along rutted tracks to disappear underground and reappear to collect more leaf fragments from a far source. Such lives of endless toil appear to be never-ending.

This leaf-cutting species works continuously to keep its fungal farms in production. The ants live on fungi that grows in their formicaries, or colonies, nurtured by leaf fragments which are further reduced by a separate team of stalk cutters before being laid out in ‘gardens’ to be tended by yet another crew.

There is careful husbandry: if a leaf source is found to be toxic, the ants promptly move to another. Source sites may be up to 300m away but, like slugs, the insects follow a scent trail laid down by the original surveyors. Individual ‘soldiers’, separate from the constantly moving lines, are on the lookout for intruders who might steal the crops. Colonies can also be raided and resident insects enslaved. Within the formicaries, reigning queen ants — who can live for up to 15 years — preside over colonies of between 100,000 and 500,000. The largest was found in Switzerland in 1977 with 300 million living in 1,200 anthills crossed by 60km of paths in the Jura Mountains.

Most of us have had unpleasant encounters with ants, red and black, in this country.

In Africa there is a species called Matabele which have remarkable human-like traits in that they save wounded comrades on termite battlefields. If an ant can stand on just one leg after a fight, it is carried off to have its wounds tended to by triage ‘doctors and nurses’ to fight another day. Prone casualties, however, are left where they fall.

A scientific report recently suggested that ‘ant power’ in crop production can be more efficient than chemicals. The ants are better at disposing of pests, thereby reducing damage and increasing yields. An analysis published in Proceedings of the Royal Society looked at 17 crops in several countries and found some ant species with proper management had similar or higher efficacy than pesticides — and at lower cost.

However, ants can also be a problem where meal bugs, aphids and whiteflies are concerned. They produce a sugary substance called honeydew to which ants are attracted and which they ‘farm’ like livestock. But researchers say alternative sugar sources may be used to distract the ants so they continue to attack the other pests.

There are more ants than any other insects in the world, about 14,000 known species, making up about half of the earth’s biomass. They are incredible creatures.