We are of course talking about the UK’s largest ant species: the southern wood ant. However, this species isn’t known purely for its predatory success, it has also developed a fascinating, more passive way of sourcing its favourite food. 

At around 1cm in length, the southern wood ant uses its large mandible (insect mouth) to feed on a wide variety of insects and invertebrates which the worker ants collect from the area surrounding the colony. Surprisingly, its favourite food is actually honeydew. This is a sweet, sugary substance that is secreted by aphids (small sap eating insects) and which makes up the bulk of the ant’s diet.

The ant has found an ingenious way of sourcing their favourite food, which has also created a symbiotic relationship with the aphid. The ant strokes the abdomen of the aphid with its antennae, stimulating the secretion of honeydew. The presence of the ants in-turn protects the aphids, deterring attacks from other predators. It is believed a single colony can consume up to a quarter of a tonne in a year!

Found in Southern England and Wales, the southern wood ant lives in both coniferous and broadleaved woodland, as well as on heathland and moorland. The ants like to live in large nests made from soil, twigs, pine needles and other fallen leaves. They are not fussy where they build their nests, so long as the sun can reach their chosen spot. These nests house colonies numbering in the tens of thousands and sometimes up to half a million southern wood ants can be found in one site.

A colony comprises of a queen or queens, non-reproducing female workers, and males which mate with the queen(s). Come springtime a generation of males and females, which are able to reproduce, will be raised. They take to the air to mate with the fertilised females, eventually shedding their wings and dispersing to form new colonies.

As well as being a formidable hunter, the southern wood ant (which is also known as the red wood or horse ant) employs a novel defence mechanism: it can spew formic acid to defend itself!