Insect life is booming on the Chayne, and the first swarms of midge are starting to swirl over the bogs. There is still frost at night, so I was surprised to find a number of caterpillars clambering along the grass stalks and over the heather this morning. Apparently fearless of attack from birds or animals, these bristling two and a half inch long cylinders seemed happy to blindly clamber across the moor.
When I prodded one with a grass stalk, it was horrified and curled itself into a tight ball, bristles pointing outwards, but it soon uncurled itself and set off on its travels once more. They were scattered fairly sparsely, but once I started to keep an eye out for them, I began to notice several more. It was only when I returned home and identified them that I began to have concerns. It would seem that they are the caterpillars of the macrothylacia rubi, the common fox moth, and they particularly enjoy eating bilberry and heather. Turning to the appropriate page of my GCT Red Grouse and Moorland Management guidebook , I saw that these caterpillars periodically undergo massive population booms, laying waste to heather stands and decimating grouse habitat.
They may not be causing much damage at the moment, but it could be that fox moth caterpillars will become a problem at some point in the future.