Country diary: walking the wild expanse of Teifi Marshes

Groups of geese cruise the creeks of the Afon Teifi. Photograph: John Gilbey

Shimmering through a blend of August afternoon heat haze and the swirling movement of reeds in the strong westerly wind, the wild expanse of Teifi Marshes was sunlit and inviting. The flooding tide in the river and the open arc of the sky were uniformly blue, with white fair-weather clouds reflected in the still water of the more protected pools.

Before this area was glaciated, the Afon Teifi appears to have looped south of the narrow gorge it now occupies at Cilgerran. The abandoned route has left a broad, low-lying valley whose sides – clearly cut by a wide, meandering stream – are thick with trees. In the 1880s, the dynamic of the landscape was changed further when the Whitland and Cardigan railway constructed a causeway of dark, blocky furnace waste across the marshland. This impeded the ingress of seawater and began the evolution of the predominantly freshwater environment visible today.

An old route of the Afon Teifi hosts extensive reed beds. Photograph: John Gilbey

To the south of the old railway line, which is now a welcome route for those walkers who appreciate dry feet, stands of reed almost encircle areas of open water – the brittle hiss of their stems and seed heads moving against each other blanketing out other sounds. Groups of duck preened and dozed on the low mud banks, while a larger contingent of Canada geese argumentatively cruised the creeks of the main river channel to the north.

Willowherb shedding seeds. Photograph: John Gilbey

A flash of blue seen fleetingly in the corner of my eye made me wonder if there was a kingfisher nearby. Although I paused at the spot and waited, I saw nothing else, but another walker asked me later if I had seen one – and, to my chagrin, reported seeing it perching in full view.

Despite the recent rain the blackberries were still hard, small and unripe, but the blackthorn bushes alongside the path were heavily laden. The sloes were already darkening from green to the deep blue of remembered childhood ink, their skins mottled with a characteristic lighter bloom. As the afternoon heat grew stronger the breeze also strengthened, filling the air with the floating, invasive seeds of the rosebay willowherb. Summer might not yet be over, but the signs of its demise are building rapidly.