Digging for wildlife at Penhale Dunes

Cornwall Wildlife Trust have announced that the works beginning on Monday August 21st will involve using earth-moving machinery to create ‘V-shaped notches’ in the sand dunes, as part of a project to help restore natural dynamic processes and support the area’s wildlife.

Penhale is one of the largest dune systems in Cornwall, spanning 620 hectares (1,532 acres). With sand dunes listed as the habitat most at risk in Europe for biodiversity loss, it’s an incredibly important area to protect for nature. These works will rejuvenate this area of mobile dunes, helping the many species which make use of open areas of bare sand.

Jon Cripps, Penhale Dunes Ranger at Cornwall Wildlife Trust said:

“The work will look quite dramatic as it’s unusual to see big diggers on the dunes, shifting loads of sand. However, this short-term disruption should create long-term benefits for lots of dune-adapted wildlife.

“We’ll create open spaces for plants like sea holly and sea rocket to colonise and lots of warm sandy niches for the various insects that burrow into sand, such as the tiny silvery leaf-cutter bee, the minotaur dung beetle and the predatory bee-wolf wasp! We hope the scale of the work will allow the wind to whistle through the dunes and keep these areas mobile, dynamic and diverse for many years to come.”

Tiny silvery leaf-cutter bee on humans thumb — (c) Tiny silvery leaf-cutter bee, by Sally Luker

The sand dunes at Penhale are both nationally and internationally important for their diverse range of coastal habitats and are one of the largest sand dune systems in southwest England. The area is designated nationally as a Site of Special Scientific Interest (SSSI) and internationally as a Special Area of Conservation (SAC). They are home to a wide variety of wildlife, such as the much-loved silver-studded blue butterfly, scrambled egg lichen, skylarks, adders and protected plants such as petalwort, early gentian and shore dock.

Sand dunes need to be free to move to support their resident wildlife and provide them with safe homes. Areas of naturally shifting mobile sand are essential to them being healthy and diverse ecosystems. Many burrowing insects require bare sand as part of their life cycle.

Sadly, many sand dunes have become too stable and overgrown with dense vegetation. Sand dunes are now one of the most threatened habitat types for biodiversity loss in Europe. The percentage of precious bare and mobile sand at Penhale Dunes has dramatically reduced over recent decades. It is estimated that around 50% of Penhale Dunes comprised bare sand habitats in the 1940s; this has now reduced to less than 2%.

A variety of reasons have led to this change, including a lack of large grazing animals eating dune plants and air pollution creating higher levels of nitrogen deposition which increases soil fertility, leading to increased plant growth and the spread of invasive plants.

Two silver-studded blue butterflies — (c) The silver-studded blue butterfly is one species doing well at Penhale Dunes, by Adam Poledníček

The restoration works taking place at Penhale Dunes form part of Dynamic Dunescapes, a collaborative project working to restore 7,000 hectares (17,297 acres) of sand dunes across England and Wales. The works involve funneling wind-blown sand from the beach into the dune system behind. V-shaped notches will be created by diggers, and the area around these will also be stripped of turf, to create more bare sand habitat and to encourage these dunes to be more mobile again. Although these works may appear destructive, they are being done for the purposes of habitat restoration.

‘Notches’ have been successfully created in other parts of the UK as part of the Dynamic Dunescapes project, including at Formby and Ainsdale, on the Sefton Coast. This will be the first time the technique has been used in Cornwall.

During the works, access to the coast path, which runs along the beach at this point, will be unaffected. However, there may be slight delays on the permissive route along the dune ridge, as machinery crosses. For safety reasons Cornwall Wildlife Trust and landowners the Defence Infrastructure Organisation (DIO) ask people to please keep away from machinery at all times.

This area of Penhale Dunes is used as a military training area, so any land except the permissive path is off limits to the public. However, Cornwall Wildlife Trust have been working here in partnership with the Ministry of Defence’s DIO for over 15 years, balancing military needs with ecological conservation work.

Lt Col Andy Westcott (Retd), Training Safety Officer for Cornwall Defence Infrastructure Organisation said:

“We are extremely proud to be working with Cornwall Wildlife Trust on the Dynamic Dunescapes project. As custodians of this fantastic dune system, it’s great to see this management work happening to improve its condition and suitability for sand-loving wildlife.”