Alien ant farm

Two southern wood ants (Formica rufa) tending aphids on a ragwort plant.

I went for a quick walk on Arnside Knott this morning before work, hoping to see a scotch argus butterfly. We are in to their flight period now, but perhaps it was too cool and damp, since I didn't see any.

I did find a colony of these aphids on several ragwort plants being tended by wood ants. The ants farm the aphids for the sugary honeydew that they excrete, and in return they protect the aphids from would-be insect predators such as ladybirds. There is some evidence to suggest that chemicals secreted by the ants helps to subdue the aphids to keep them in one place, close to the ants' nest.

The southern wood ants are a large species which make enormous nests in areas where there tends to be partial but not complete shade from trees and shrubs. On Arnside Knott they reach the limit of their range in England, they are not found on the north side of Morecambe Bay. There has been a contraction of range southwards for reasons unknown, particularly as this runs counter to the northward progression of many insect species as the climate warms.

We should have been heading to Yorkshire this evening, but Wifie has toothache, and we need to try and sort out some treatment first thing tomorrow morning. Hopefully we can get her sorted out and get going after that to join Eduardo's 40th birthday celebration.

ps. This is exciting. I've discovered the year ago button to press, and there are blips to show. A year ago Wifie had a bad hair day.