Ants in your plants!

Wood ant {Formica rufa} Arne (RSPB) nature reserve, Dorset, UK. July 2011. - Ross Hoddinott/2020VISION

There are estimated to be over 60 species of ant in Britain and over 30 have been recorded in our two counties, making our region something of a hotspot. Here are some of our favourites.

Black garden ant Lasius niger

The black garden ant is a common and widespread species and the only ant that you are likely to regularly encounter indoors. Nests contain an average of between 5000 and 7000 individuals and the queens are particularly long-lived at around 15 years. 

Black garden ants are expert aphid farmers, not only tending and protecting the aphids in exchange for the sugary honeydew they excrete but also moving the aphids to new healthy plants to ensure their continued survival. Black garden ants will also eat soft fruit and a wide range of small invertebrates

Southern wood ant Formica rufa

The red and black southern wood ant is one of the largest ants in the UK with fearsome features to match – they have an impressive pair of powerful mandibles and can also spray formic acid to deter predators. Their large distinctive mounded nests are found in woods across southern Britain. From there they scavenge and hunt for insects as well as tending aphids for their honey dew. When foraging in the canopy, large numbers of southern woods ants will fling themselves off branches to avoid predators such as birds, creating ‘ant rain’.

While the spraying of formic acid may deter many potential predators, both jays and green woodpeckers have been witnessed deliberately rolling in the nests of wood ants, apparently to use the formic acid sprayed by the ants to rid themselves of mites and other parasites.

Slave-maker ant (blood red ant) Formica sanguinea

This aggressive black and red ant is superficially similar to the wood ant, but it is smaller and nests in dead wood. These ants are called ‘slave-makers’ because they are social parasites on other ant species, most commonly smaller black ants.

They appear to have two strategies; queens may invade the nest of other ants at an early stage, kill the resident queen and effectively take over the nest; or the worker slave-makers may raid the nests of other ant species and take away larva to carry out tasks on their behalf.

These ants also are highly predatory and will attack other ant species as well as a range of invertebrates for food. When launching a raid, scouts will initially be sent out to locate a potential target nest, the slave-makers will then advance in a column of up to a 1000 individuals, excavate the entrance and attack en masse.

Although not common, slave-maker ants are found in various heathland and open woodland locations across Hampshire.