Legacy of foot-and-mouth threatens rare species

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One of Britain's most beautiful beetles is among several wildlife species facing extinction in the wake of foot-and-mouth disease.

One of Britain's most beautiful beetles is among several wildlife species facing extinction in the wake of foot-and-mouth disease.

The problem for the blue ground beetle, Carabus intricatus, and other insects is that they depend on farm livestock to maintain the habitats vital to their existence in south-west England. The crisis that devastated the sheep and cattle industry is threatening to shatter that delicate relationship.

Many farmers are considering pulling out of livestock, and conservationists fear that biodiversity action plans (Baps) to safeguard a range of rarities could founder if this essential element is missing or in severe decline.

The blue ground beetle was considered extinct by the Seventies but surviving populations have been found in seven ancient pasture woodlands, four around Dartmoor, Devon, and three on the edge of Bodmin Moor in Cornwall.

Blue ground beetles, the largest and most beautiful of the ground beetles, grow up to one and a half inches long and eat slugs, snails and caterpillars. They are found only in moist oak and beechwoods in river valleys. The ground must be sparsely vegetated, because of grazing livestock, for example.

"Farmers were already struggling to make a living in these marginal areas before foot-and-mouth," said David Boyce, an ecological consultant who is working on conservation of the beetle. "There is much talk now of pulling out of livestock. That inevitably sounds alarm bells for this and other dependent species. We have been looking at helping the remaining beetle populations to spread by creating new habitat next to existing sites and converting conifer plantations to broadleaf woodlands. We hope the 1,000 acres suitable for them can be doubled over the next 50 years.

"But grazing is such an important factor that if we end up with more potential habitat but much less livestock to keep down ground cover, it won't work. With so much uncertainty over farming's future, it's impossible to predict the outcome."

Similar problems face six other rare invertebrates on adjacent moorland. One is the Kugelann's ground beetle, Pterostichus kugelanni, which inhabits bare, sandy ground – the result of livestock feeding – on south Devon lowland heaths. Two butterflies, the high brown fritillary, Fabriciana adippe, and the pearl-bordered fritillary, Clossiana euphrosyne, live on south-facing bracken slopes. They need livestock to prevent bracken spreading over open areas occupied by the wild violets on which they depend at the caterpillar stage.

Stock grazing helps bog hover flies on wet moorland patches, and fairy shrimps require animals trampling around the edges of their ponds. Hornet robber-flies also have a special need; at the grub stage they feed on the larvae of dung beetles.

Dr Roger Key, senior invertebrate biologist with the government advisory body English Nature, says: "There is so much potential for grazing in the South-west that we are optimistic there will be a recovery in the long-term and livestock will continue to play a part in the survival of these species. In areas where there are national nature reserves, which we manage, we can ensure suitable grazing occurs."