Lying just to the west of Oxford, the Cothill area is classic Oxfordshire countryside with sleepy stone houses and a welcoming pub. The real jewels, however, are hidden behind the extensive gardens and the local airfield — the Cothill Fens.

These are waterlogged places fed by groundwater and surrounded by wet woodland of willow and alder. The clean spring waters seeping out from the water table create shallow pools that are ideally suited to a massive variety of wildlife. It is nature’s own supermarket — lots of variety all in one place, meaning lots of choice for wildlife.

The BBOWT reserves in the Cothill Fens area have their own unique character; Dry Sandford Pit is a recent addition, having been dug out for sand in the 1950s and 60s.

Although this disruption was an upheaval at the time, it left behind fresh springs and pools and impressive, overhanging cliffs.

This reserve is now highly prized by keen naturalists and families out for an adventurous walk. ‘Bug-hunters’ can have a field day here as the crumbly cliffs are host to hundreds of species of ants, bees and wasps, many of which excavate tiny tunnels in the stone.

The fens at Dry Sandford Pit support impressive flies such as the clubbed general soldier fly — striped yellow and black to mimic large wasps. The pools and ditches often have manic whirligig beetles spinning in tiny circles, apparently out of all control.

All this life attracts some larger animals — frogs congregate in the spring to spawn in the ponds, along with toads and newts.

A kingfisher can sometimes be glimpsed, or heard giving its high-pitched ‘eek’ as it twists away between the bushes.

The rabbits that burrow at impossible heights in the cliffs at Dry Sandford Pit have attracted a resident family of polecats in recent years.

One of the older fens, Lashford Lane Fen, is fed by Sandford Brook and the shady track soon leads to a hidden reedbed where reed buntings can be seen and the long-sustained churring of reed warblers can be heard.

Water voles busy themselves on the banks of the brook, weaving in and out of the sedges. At nearby Parsonage Moor, the hypnotic call of the cuckoo is a typical summer sound as they stake out the reeds, waiting for a chance to drop an egg into a reed warbler nest.

Described as ‘successional’ habitats, fens will move fairly rapidly towards a densely wooded state and become impenetrable if neglected.

Grazing is just one way this can be prevented, helping to keep the diversity of species that rely on the fen habitat. BBOWT has already seen the benefits of livestock in this area — ponies were introduced to Parsonage Moor in 2003.

By browsing on young trees and the dense reeds, they have created light, open patches and pools in the fen.

It has been so successful that in 2005 rare southern damselflies were recorded on site for the very first time. Looking like tiny matchsticks of electric blue drifting on invisible wings, these dainty insects resemble their close cousins, the common blue and azure damselflies.

There is a special difference though: the nearest known colonies to Oxfordshire are in the New Forest and South Wales.

Establishing a new population so far from their homeland is an exciting result. Numbers of other plants and insects have increased too: dragonflies, including keeled and black-tailed skimmers and insectivorous butterwort, among them.

For more than 40 years, BBOWT’s volunteers and staff have been working to improve the Cothill habitats for these species and more. This year, a new project funded by SITA Trust (through the Landfill Communities Fund) has been launched to secure the future of the Cothill Fens.

With project officer Louise Print-Lyons onboard, plus the help of local volunteers, the Cothill Fens Project will focus on four BBOWT reserves, improving and restoring fenland and helping numerous species in the process.

Thanks to the new project, BBOWT can extend its work further still, introducing Dexter cattle at Dry Sandford Pit next year and building new livestock enclosures at Lashford Lane Fen. These small cattle are light-footed and keep advancing reeds at bay, providing exactly the right mix of conditions for a wide range of wetland plants.

Martyn Lane, senior Oxfordshire reserves manager at BBOWT, believes the project will have a great impact on the habitats of the area: “I’ve long held an ambition to introduce grazing animals to new parts of the Cothill Fens but could never get it done with the resources available.

“This project is just what is needed to release the potential of the area. I’m looking forward to seeing how the Dexters behave in their new home at Dry Sandford Pit.

“It will be fascinating to see the gradual changes to the habitat that their browsing will bring about.”

Fens are not the only habitat set to benefit — grassland, meadows and woodland will be improved too.

Not only that, the project will also provide an exciting opportunity for local people to get involved in some hands-on work.

Much of the day-to-day care of BBOWT’s Cothill reserves is seen to by local volunteers and BBOWT will be recruiting and training additional helpers too.

To get involved in stock watching, practical conservation work and more contact Louise Print-Lyons, Cothill Fen project officer, on 01865 775476 ext 237 or email louiseprint-lyons@bbowt.org.uk