February chalk-stream grayling study
February Chalk‑Stream Grayling on the Test and Itchen

Cold‑water feeding windows
On Hampshire's Test and Itchen, February creates narrow feeding windows for Thymallus thymallus as sub-5°C water temperatures slow metabolism but retain exceptional clarity. Grayling will rise in low light or brief thermal bumps from groundwater seepage, producing bursts of activity often less than an hour long. These pulses are predictable where springheads, troughs and clean gravel intersect.
Nymph patterns and drift lengths
Successful presentations mirror minute olive and pheasant-tail nymphs in long, dead-drifted runs. Chalk-stream grayling frequently take at the tail of a seam; subtle trailing shucks and sparse flash provoke takes more than bulky flies. Long drifts — extended by angler positioning into gentle tails — exploit the species' reluctance to chase in cold water.
Reading February seams and signs
Low February flows expose tail-outs, clear seams and marginal springlines; anglers look for pale gravel patches, filamentous algae off gravel shoals and steady trickles of slightly warmer water. Those microhabitats presage the spring rise and concentrate drifting invertebrates, making them reliable marks before the river's seasonal turnover.
Late‑winter clarity and presentation
Chalk aquifer-fed clarity forces subtlety: flies with muted tones and reduced profiles match the subdued February hatch spectrum. The Test and Itchen's history — celebrated in Izaak Walton's The Compleat Angler and in the dry-fly tradition of Halford-era Hampshire — makes these methods part of a continuing local orthodoxy, yet winter grayling demand quieter, nymph-centric tactics.
Signals before the spring rise
Before the spring rise, watch for subtle increases in suspended fine organic matter, a shift in invertebrate drift toward larger chironomid pupae, and the first warmer seams from hillside runoff; these herald increased feeding and more extended daytime windows.