Eison to Becs de Bosson

The day started from Eison, which was a short drive from the campsite at Évolène. From 1661m starting altitude the path took us up through fields, quite steep but with interesting species flying including Knapweed fritillary, Melitaea phoebe and Marbled ringlet, Erebia montana.

At about 2000m altitude the fields ended and the terrain turned rougher. Mainly sparse grassland with a few flowers. A small stream seemed the focus of most of the species flying in this area. Mountain fritillary and Shepherd's fritillary Boloria napaea and Boloria pales were on the wing together with Swiss brassy ringlet, Erebia tyndarus.

A little further on we joined a larger track, which was heading towards the Pas de Lona. Here the grassland had more flowers and the track itself attracted dozens and dozens of ringlets, they were particularly keen to land on the soft earth banks, presumably to collect some salts from the earth. We had lunch above the track, rather disturbed by Eros blue, Polyommatus eros, Peak white, Pontia callidice, Dusky grizzled skipper, Pyrgus cacaliae and Mountain clouded yellow, Colias phicomone

After we had chased these species and managed a little lunch we continued on just past a little hamlet, L'A Vieille. I followed up a rocky stream bed, we had now reached 2500m and true Alpine grassland. The Butterflies were very different, much smaller, but still intricately marked. Glandon blue, Agriades glandon, Grison's fritillary, Mellicta varia, Cynthia's fritillary, Hypodryas cynthia, Mnestra's ringlet, Erebia mnestra, Alpine heath, Coenonympha gardetta, Alpine grizzled skipper, Pyrgus andromedae and Cranberry blue, Vacciniina optilete were all flying together with the tiny debilis form of the Marsh fritillary, Euphydryas aurinia which was exquisite. Probably the most enjoyable couple of hours Butterflying I've ever had.