The nature of things
THE Roman author Aelian described brown trout as the ‘fish with speckled skins’. In medieval times, Dame Juliana Berners, the sporting Benedictine nun, relished it as ‘a right dainty fish and also a right fervent biter… in season from March until Michaelmas’. Izaak Walton’s The Compleat Angler (1653) salutes the trout as ‘highly valued, both in this and foreign nations. He may be justly said, as the old poet said of wine, and we English say of venison, to be a generous fish that… comes in and goes out of season with the stag and buck… a fish that feeds clean and purely, in the swiftest streams, and on the hardest gravel’.
From spawning in early spring, most young trout (some 95%) die within their first year and, although they lack scales in the first month of life, the growing survivors develop tiny growth rings on their scales, enabling age calculations, like the rings on a tree. As with leopards, the trout’s spots ensure camouflage for this opportunistic hunter of streambed invertebrates and small creatures on or near the water’s surface. Sea trout are of the same species but migrate to the ocean, returning to freshwater only to spawn. Rainbow
trout (top left, top right), a Pacific Ocean species, was introduced here in the 19th century, but seldom interbreeds with browns, other than on fish farms. KBH