Gammarids
It rises in the Pays d'Auge — apple country, Calvados country — and runs north through Lisieux to the sea at Deauville, a chalk stream carrying clear, stable water over clean gravel for most of its fifty-odd kilometres. The fish counter at Breuil-en-Auge recorded over six thousand sea trout in 2023, and the basin is estimated to hold five to six thousand fish in a good year. This is not a marginal fishery clinging to existence. It is the most abundant sea trout system in France, and it fishes accordingly. Sea trout enter from late April and run through October, with the main body of fish arriving June through August. Fish the lower river and its tributaries — the Calonne, the Orbiquet — on the drop after rain, when colour gives the fish confidence to move. Evening and night fishing from June, floating line, size 10 wet flies fished across and down. The Touques is open water in a country where most migratory salmonid fishing is now closed. Fish it while it lasts.
In chalk-spring and karst trout systems, generally stable temperatures broaden olive and other mayfly activity from early spring into autumn, with strong evening caddis, steady subsurface scuds and buzzers where clear groundwater and weedbeds develop, and terrestrials from meadow and woodland banks rounding out the food calendar, depending on how fast each river drops and clears after rain.
- Chalk