Saturday saw us at the top of Blake Fell at the far west of the Lake District hills. The views were a little hazy but extended along the Cumbrian coast and inland to the hills around Buttermere and Ennerdale. However, it was a very large fly that took our attention on arrival at the summit. This huge black creature – well, huge in fly terms – was buzzing around the little rock shelter at the top. With a sparsely hairy abdomen and pale face it was a slightly unnerving looking insect; however, it was the local caterpillars that needed to look out. This giant tachinid fly (Tachinia grossa) seeks out large caterpillars and lays its eggs inside them, the eggs hatch and the larvae eat and, eventually, kill the host. Perhaps the Emperor moth caterpillar seen earlier in the walk was in danger, or already parasitised.
On a slightly lighter note, the butterflies around Cogra Moss, nestling below Blake Fell, provided a welcome splash of insect colour. Small tortoiseshells, red admirals and meadow browns were all to be seen on the thistles while small heaths fluttered over the flanks of the hills.