May – River Fly Selection

May is a transitional and often productive month for UK river fishing, with improving water temperatures and a wider range of insect life becoming available to trout.

As the month progresses, Large Dark Olive hatches typically begin to tail off and are gradually replaced by other upwinged flies. Iron Blue Duns, Medium Olives, and other spring olives become increasingly important, particularly on cooler or unsettled days when fish continue to favour smaller, darker profiles.

Towards the latter part of May, Mayflies should begin to appear on rivers where they are present. Early hatches are often sporadic and highly weather-dependent, but when conditions align they can bring some of the most exciting dry fly fishing of the season.

Stoneflies continue to feature on suitable rivers, often alongside growing numbers of Alderflies and early sedge activity. These larger flies can provide confident surface feeding, particularly on faster, well-oxygenated systems.

Terrestrial insects also start to play a more consistent role. Hawthorns may still be present, especially during warm spells, and the arrival of Black Gnats on the water can bring steady surface feeding, particularly during calmer conditions.

While dry fly opportunities increase through May, subsurface patterns should not be overlooked. Nymphs and other subsurface food sources remain important, especially during periods between hatches or when conditions suppress surface activity.

The flies in this collection have been selected to reflect typical UK May river conditions, covering a broad range of emerging insects and terrestrials while retaining the dependable subsurface patterns that continue to produce fish.

If you’re unsure which flies best suit your local river or current conditions, we’re always happy to help.