Stoneflies
It holds the same wild Atlantic salmon stock as the Sée and Sélune — unsupported by hatchery work, small in numbers, historically significant. Salmon and sea trout fishing are both closed throughout the Seine-Normandie basin under the 2026–27 basin order. The brown trout populations in the upper reaches and tributaries are strong: wild fish in granite pocket water, Baetis and stonefly hatches through spring and summer, good dry-fly work in June and July. The gorge sections above Saint-Lô, where the river cuts into granite bedrock and concentrates its current into proper pools, are the best of it.
On Atlantic trout rivers in Normandy and Brittany, regional studies and on-the-bank experience point to spring mayflies as the main early driver, a strong band of spring and early-summer caddis as channels warm and open, background buzzer life ticking away right through the year, and terrestrials from wooded banks adding important surface food in summer and early autumn, with autumn olives extending sport wherever trout-season rules allow.
- Granite