Country diary: A fly is never just a fly | Mark Cocker

Buxton, Derbyshire: St Mark's flies are out in force, food for the swifts and starling chicks, and everything else besidesExamine any part of the horizon from our garden and you find the air freckled with slow-dreaming swarms of black dots. I'd hazard a guess that all of them are Bibio marci, a fly named because it's said to emerge on the feast of Saint Mark - 25 April.All spider webs inspected thus far have contained their remains, but a larger revelation came from some cattle troughs 10 miles from here. The surface film was full of drowned insects. The fly of St Mark is so often a corpse that you could easily imagine that its species' raison d'?tre was to exit life as casually as possible. Those many victims, however, hint only at the creature's astonishing abundance. For the ensuing weeks it will be probably the most numerous macro-organism in our countryside. Continue reading...