Flying native of south London faces fast decline

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The Independent Online

Environment Correspondent

On a midsummer evening in the south London suburbs, a large black speck can sometimes be seen waltzing erratically through the air at rooftop height. It appears much too big to be an insect, too small and slow to be a bat or bird.

But it is an insect; Britain's second largest. This is the huge stag beetle, which is about the same size and weight as Britain's smallest mammal, the pygmy shrew.

The males carry huge mandible (jaw) extensions from their mouths which resemble the antlers of stags. They are often over two inches long, and the largest found in Britain was just over three inches. The females are large, too, but lack the formidable mandibles.

The beetles are now on a list of 116 rare or fast declining plant and animal species for which rescue plans have been proposed to Government. The list was selected by a committee of Government conservation scientists, wildlife charities, civil servants, academics and landowning interests.

For unknown reasons, the insect's stronghold is south London and it is also still widespread in the Thames valley, north Essex, south Hampshire and West Sussex. But it is in decline in Britain and the rest of Europe.

Its first three or four years of life are spent as a larva, munching its way through large pieces of decaying, deciduous wood - often in roots and stumps.

Then it turns into a pupa and metamorphosises into the adult. These fly around in search of a mate, and only live for a few weeks.

Despite their fearsome appearance, they are incapable of harming people. Yet all too often the reaction of urban man on finding one is to stamp or smash it to death - which may be a factor in its decline.

A more important reason is the removal of dead wood, as parks and copses are tidied up.

The rescue plan's objectives are to identify the beetle's key sites, maintain its population and find out what its habitat requirements are. Local councils and landowners with parks and woodland must be encouraged to leave decaying stumps in which the larvae can live.