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Ecology

As our archaeologists excavated evidence of past environments, our ecologists studied today's heathland and grassland habitats, seeking not only to minimise disturbance, but to provide positive environmental gains. Here, with examples of the species that benefited, is how we did it.

The Marsh Fritillary Butterfly

The rare marsh fritillary butterfly lives on heathland and grassland areas around the A30. We planted numerous seeds and seedlings of a plant called the devil's bit scabious, which is the only food eaten by the marsh fritillary caterpillars. They weave a web around the plant while they feed, to protect themselves from predators.

The caterpillars spend all winter in clumps of grass and emerge as butterflies in May or June. Marsh fritillaries only travel short distances, remaining in their home patch for their entire adult life. Both the heathland and grassland derive from man's past activities, particularly tree clearance and agriculture.

Insects

Our ecologists sowed wild flower and heather seeds along the sides of the new road, to create new habitats for the marsh fritillary. By downgrading the old road, we also made it possible to join two areas of Goss Moor, reuniting two habitat areas.

Rehousing Reptiles

Four types of reptile were found along the A30 corridor: adder, common lizard, slowworm and grass snake. These are all protected species, and we captured and moved them carefully, by hand, to more favourable areas.

We temporarily fenced off large areas and then laid down a number of 'tins' - metal sheets. Some 2000 tins were used during the project. Reptiles like to bask and hide under these tins, making it easier for us to capture them. We created new or improved habitats using logs, stones and rocks, or by making new wildlife ponds.

Dormice

Dormice live in scrub and hedgerow areas, so we searched these by hand, before using machinery to clear vegetation. This was done when the dormice were active (they hibernate in the winter) but not during the breeding season, allowing them to move to other areas away from the road building. We linked dormice habitats by planting Cornish hedges, including their favourite food plants, and we also put up some dormouse nest boxes. Our ongoing conservation work will include monitoring of the nest boxes.

Otters

Otters regularly use the Goss and Tregoss Moors as part of their home range. A male or dog otter can occupy a territory of up to 6 kilometres and travel long distances to its feeding area, crossing roads where they cross its territory. In the past, otters have been killed on the A30. We have now built permanent otter tunnels under the new road, with fencing to keep them away from the traffic.

Badgers

We needed to move some badger setts away from the new road, so we fitted the setts with a gate that allowed badgers to leave the but not re-enter. The badgers respond to this by exploring other nearby setts and then choosing one to settle in.

The road can divide badger feeding areas, so we built special badger underpasses combined with fencing to keep them off the dual carriageway. 

Bats

Four species of bat are known to use the fields and hedgerows around the A30 - the common pipistrelle, brown long-eared bat, natterer's bat and Daubenton's (or whiskered) bat. It was important that we planted new trees and hedgerows to replace any that were removed, as these are used by bats to find their way to feeding areas. We also put bat boxes up in trees, for bats to roost in during the summer months. As part of our ongoing conservation work we will be monitoring these boxes.