The España is a slate-fed tributary in the Asturian network, spate-responsive and amber-toned throughout. The upper reaches show step-pool through Cantabrian slate; the descent is steep and response to rainfall pronounced. The España maintains its responsive character — quick rise, quick fall, full connection to mountain weather — throughout its reach. The available pools are secondary to the character of descent and response.

Wading: Muddy lower glides and soft estuarine bed

In the mountain-to-sea trout rivers of Asturias, olives and other mayflies do much of the work in spring whenever levels and colour allow, followed by strong evening caddis and steady buzzer life through early and mid-summer, with terrestrials and mixed surface food from wooded, pastoral banks rounding out the diet whenever flows drop back into safe wading range.