Caddisflies
The Fillière feeds the Fier from the Bornes massif and carries enough limestone character to behave like a miniature Jura stream — clear, cold, and stubbornly selective. It's not long and it's not big, and the pools are short enough that you'll fish the whole river in a morning if you move quickly and know what you're doing. The trout are wild, small, and educated; they've seen the hatches come and go for their entire lives and they are not easily persuaded. Match the olive, drop it on the cushion above the fish, and try not to false-cast over the pool. The canopy is tight in places — a 7ft 3-weight is the right rod. Spring and early summer are the moment. By August the flow thins and the fish retreat under the cut-banks where you can't reach them.
- Limestone