Picos de Europa:
a naturalist's paradise - part 4

The glacial lakes of the northern reaches

Another high-level focal point of the Picos de Europa is the Covadonga glacial lakes: Enol and La Ercina. The surrounding sward is kept short by herds of the autochthonous casina cattle which spend the summer here, but nevertheless produces a breathtaking display of hoop-petticoat Female Broad-bodied Chaser
Libellula depressa © Teresa Farino daffodils and dog's-tooth-violets in spring and merendera in late summer. Limestone outcrops around the lake are worth examining for blue-leaved petrocoptis, confined to the Cordillera Cantábrica, Pyrenean lousewort and deep-purple-flowered clumps of the Picos de Europa's endemic toadflax Linaria faucicola.

An additional attraction of the lakes is the tens of thousands of common and azure bluets that swarm around the margins in mid-June. The peripheral beds of bogbean and sedges should also reward you with four-spotted chaser, blue emperor, keeled skimmer, common goldenring and red-veined and ruddy darters. Look out too for Iberian rock lizard in rocky habitats, rock thrush around the cliffs at the southern end of La Ercina, and citril finch in the beech forests slightly further afield.

La Garganta Divina

The Garganta del Cares is probably the pick of the river gorges which dissect the Picos de Europa. An 11km trail follows the whole length of this steep-sided chasm, often several hundred metres above the river, giving you a good chance of spotting Sticky Flax
Linum viscosum © Teresa Farino wallcreeper in winter and black woodpecker (in small enclaves of broad-leaved forest) at any time of year. Crag martin and dipper are present all year round, plus alpine swift in summer, with blue rock thrush a distinct possibility at the northern end. Shady overhangs shelter maidenhair fern, round-leaved St John's-wort and large-flowered butterwort, while sunny limestone rockgardens host sticky flax, woodcock ophrys, fragrant orchid and dark-red helleborine.

Among the butterflies which frequent the warm, sheltered reaches of the gorge in June are marbled skipper, Berger's clouded yellow, Moroccan orange tip, violet fritillary, pearly and dusky heaths, marbled white and Spanish purple hairstreak. To the south of Caín, mixed deciduous woodland around Las Vegas is a noted haunt of woodland brown, one of Europe's rarest butterflies, at a distance easy to confuse with the rather similar ringlet: one of just three colonies known in the Picos de Europa.