Stoneflies
Gammarids
A major limestone river carrying wild brown trout throughout and a run of salmon and sea trout through the lower reaches. The Carlow water is good trout fishing, with solid mayfly and olive hatches, and the Barrow — one of the longest rivers in the country — rewards the kind of patient exploration a shorter river doesn't need. The clear limestone water allows genuine sight-fishing. Quality browns hold the upper reaches; the lower river suits dace and roach better than trout. For 2026 this is catch-and-release only under the Wild Salmon & Sea Trout Tagging Scheme — every salmon and grilse goes back.
EPA invertebrate monitoring across the Barrow's WFD segments confirms mayflies, stoneflies, caddis, midges and blackflies, and freshwater shrimp, hoglice and white-clawed crayfish are all present in the food base. This is presence data from kick sampling, not a hatch calendar — it says nothing about when these groups are on the wing or how often trout see them at the surface.
- Limestone