Exploring Letcombe Valley nature reserve

Take a virtual stroll around Letcombe Valley nature reserve and discover the wildlife along this rare chalk stream

Letcombe Valley nature reserve, near Wantage in south-west Oxfordshire, contains a lovely mix of woodland and chalk grassland, centred on a stretch of the Letcombe Brook, a globally rare chalk stream habitat.  

As you enter the reserve from Bassett Road you cross the Letcombe Brook. Look down into the shaded water immediately upstream of the bridge and you might spot a brown trout sheltering in the quieter flow waiting to intercept food washed down in the current. The brook’s clear waters are also home to unusual fish such as bullhead and brook lamprey.

Brown trout

Brown trout by Jack Perks

Follow the narrow, shaded track along the brook. Volunteers are working to create a wild-life rich chalk stream. Overhanging trees and plants are cut back to reduce shade, providing the right conditions for aquatic plants such as water mint and starwort. Woody debris is used to create flow deflectors, which narrow the stream and increase the flow. The fast moving water washes away any silt to expose the gravel bed where fish can spawn and invertebrates thrive.  

You may spot a water vole in the rich bankside growth of watercress, brooklime and water forget-me-not. Listen quietly and the loud munching, or a ‘plop’ as it enters the water, may help you locate one!

Water voles filmed on the Letcombe Brook at a private site, upstream of the nature reserve

As you join the main path through the field, there are large ant hills on the right, and beyond them an old dam that once provided hydro-electricity to a large house nearby. Through the gate ahead is a pond recently dug and planted by volunteers. Isolated from the brook, it allows different species, especially newts, to thrive safe from predation by fish, and also provides pond-dipping opportunities for children.   

During the summer, the lake created by the dam is a great spot to look for dragonflies skimming low over the water, hunting for their insect prey. Species seen here include the southern hawker, brown hawker and common darter along with the tiny, bright blue common and azure damselflies. At dusk, Daubenton’s bats swoop low across the lake feeding on insects at the water’s surface.

Southern hawker by Brian Walker

Southern hawker by Brian Walker

Little egrets, which appeared as winter visitors to the area several years ago, may now be seen at any time of year, sometimes perched in the trees on the far side of the lake. 

The clearing is used for the annual "Discovery Day" each summer, organised by the volunteers – a few hours of activities and exhibits for all the family to learn about and enjoy the wildlife that lives here.   

On the far side of the clearing, follow the path into the woods upstream, pause at the top of the slope and look to your right. This vantage point gives you a great view of the brook as it flows through a figure of an 'S' far below. You may glimpse that electric blue as a kingfisher flies fast and low downstream. 

Springs within the woods create unusual chalky formations that support some rare specialist insects.

Continuing along the path upstream the grass bank comes into view on your left. This area has been returned from dense scrub to open grassland, which has been scythed by volunteers and grazed by livestock to improve its biodiversity. In spring, twayblades (a type of orchid) can be found in this area.  

After climbing the steps, turn left and follow the flat top of the steep bank, the so-called ‘Old Bassett Road’, back to the pond. From this raised position looking across the Letcombe Valley to the downs scan the skies for birds of prey. Red kites are rarely out of view here but you may also spot a buzzard or kestrel.

The real prize is a sighting of a peregrine or hobby – both have been seen by lucky visitors in the past!

After you pass the clump of trees, the path slopes down to the pond. In summer, the knapweed, lady's-bedstraw and field scabious on the slopes either side of the path attract butterflies such as marbled white. If you catch a glimpse of a golden-winged butterfly, it may be a comma but silver-washed fritillary are also occasional visitors here. 

Silver-washed fritillary

Silver-washed fritillary by Jim Higham