Sunday, February 18, 2007
Ants (Formica rufa) gathering sunshine
I was in Broadwater Forest, just south of Tunbridge Wells (and just in East Sussex) on a beautiful spring-like day earlier this week. One very striking feature was the huge wood ants (Formica rufa) nests that are common along most of the rides.
The warm sunshine had brought the ants out into the open but, instead of running allover the nest and everywhere else as they usually do, they were clustered tightly together in dark patches around the nest entrances. As they were not engaged in any food gathering activity, it would seem this behaviour was simply to warm themselves up before going back into the dark. Maybe they take a little heat indoors with them; maybe, like some humans, they enjoy sunbathing; or maybe they are unaware that the sunlight if February is likely to be of short duration.
John Pontin in his excellent book The Ants of Surrey (2005) says the insulation provided by the nests "retains the metabolic heat of the ants' activity", so perhaps they are gathering sunshine.