Britain proves too hot and too wet for vanishing crane fly

The crane fly, once an integral feature of the British high summer, has been strangely absent from homes and gardens this year.

Tipula paludosa or daddy-long-legs, the most familiar of the 350 species of crane fly, would once pour through open windows or doors in August and September.

They seemed to be everywhere – neglect your drink in a pub garden and within moments one would be drowning in it.

To farmers and gardeners, their undersoil larvae, known as leatherjackets, were irritating pests, but whether one regarded crane flies as a nuisance, with indifference or enthusiasm, to overlook them was impossible.

Extreme weather, a reduction in the extent of grassland so vital to them caused by increased arable farming, and attacks by parasites on their larvae could all be factors in their demise, said Alan Stubbs, the organiser of a national crane fly recording scheme.

"Populations are still recovering from the 1990s droughts, which had a bad effect on larvae in the soil," Mr Stubbs said.

"The problem more recently has been too much rain; larvae are drowning in the water-logged ground. They are more adapted to a cool, moist climate, rather than one that is too wet or dry, and they also need lots of undisturbed grassland.

"Arable farmland, especially fields ploughed to the margins, won't have any crane fly larvae."

Mr Stubbs added that in large areas of arable farmland crane flies' only refuge might be garden lawns.

Government plans to increase housing development on "brownfield" sites could squeeze crane flies and other wildlife further because such derelict plots often had a richer range of nature than intensively farmed "green" land, Mr Stubbs said.

Farmers and gardeners are anti-crane fly, believing that leatherjackets attack grass roots, but Mr Stubbs said horticulturists had no reason to celebrate their decline. "I have studied crane fly larvae for 40 years and have hardly ever come across the sort of circumstances that have led to such attitudes", he commented.

A lack of crane flies is viewed as a factor in the decline of the starling, which has joined the British "red list" of birds with breeding numbers that have fallen by more than 50 per cent in 25 years.