Invertebrates

Scottish Wood Ant (Formica aquilonia) - UK notable

The Scottish wood ant is relatively large, with a dark-brown head, a dark-brown abdomen, and a red thorax with few hairs. It is typically located in undisturbed, open woodland such as Caledonian pinewood and old birch woodland. It usually occurs along the more widespread hairy wood ant (F. lugubris). Large nest mounds (up to 1.5 m in height) made up of twigs and pine needles are built in semi-sheltered areas at the foot of trees or bushes at the edge of open areas in woodland. Nests are usually on well-drained slopes or ridges, close to clearings or woodland rides where there is some exposure to the sun. The nest mound covers a network of tunnels and chambers under the ground. It is within these chambers that the worker ants tend to the brood of eggs, larvae and pupae. The Scottish wood ant eats a range of invertebrates such as caterpillars and flies, but sap-feeding bugs are especially important, both as prey and for the honeydew they produce. Large numbers of prey are carried into the nest, although it is not known to what extent those items were scavenged or predated.

Threats and conservation

The main threats posed to The Scottish wood ant are loss of suitable habitat through agricultural clearance, urban or industrial development, afforestation and intensification of forestry. Loss of sunny woodland rides due to overgrowth and scrub invasion is also a problem although so too is over-grazing by deer. Use of insecticides in the wood or nearby may be damaging as it may bring about a reduction of available prey. Mature woodland habitats should be maintained and damage to nests should be avoided during forestry operations. For more information on wood ant ecology, habitat management and conservation, see the web pages of:

Source:

Douglas, G. 2003. Formica aquilonia Yarrow, Scottish Wood Ant (Hymenoptera: Formicidae). Invertebrate species dossier, Scottish Natural Heritage.