Forest clear-cutting causes small workers in the polydomous wood ant Formica aquilonia

摘要

We examined whether the body size of mound building wood ant Formica aquilonia workers is affected by forest clear-cutting in a before-after logging field study. Clear-cutting is expected to decrease the availability of tree-living aphids, the main food resource of wood ants. Worker size decreased from one year to the next in clear-cuts but not in forest stands, indicating food limitation in the clear-cuts. Worker size increased with nest size in forest interiors, but not in clear-cuts, which further indicates food limitation in the clear-cuts. In addition, lower body-fat contents in ant workers in the clear-cuts supports previous suggestions of lower food resources after forest logging. Nests were cooler in the clear-cuts, which suggest that they may be poor habitats for forest-dwelling wood ants. Food resource limitation may have an effect on the ability of wood ants to regulate nest temperatures.