The allure of the magical mayfly

lack-headed gulls wheeling and swooping above the small rivers I fish during early summer are a sure sign the mayfly hatch is under way, an annual bonanza that tempts the wariest of brown trout up from their lies and opportunistic gulls down from nesting colonies on the nearby moors. For the large, juicy insects they have come to feast on, these balmy days are the culmination of two years spent as small, prehistoric-looking nymphs rootling around on the riverbed in search of food. Having swum to the surface and shed their skins to emerge as drab duns, newly hatched mayflies join a jaunty flotilla gliding downstream to the rhythm of the river’s flow. Many will disappear down the gullets of greedy trout before their wings have dried sufficiently to flutter on to dry land, where they undergo a second, extraordinary transformation into exquisite, fairy-winged spinners that will never feed again; instead they dance and mate in glittering clouds all along the riverbank. Afterwards the female returns to the surface film,