Swillbrook Lakes Nature Reserve
Swillbrook Lakes lies in the south west corner of the Cotswold Water Park and is a striking example of a landscape created by human activities. The lakes were dug for gravel extraction. The Swill Brook runs along one boundary and a path allows access around the remaining sides. The site is one of a complex of Trust Reserves – Clattinger Farm, Oaksey Moor Farm Meadow, Lower Moor Farm and Sandpool Farm.
Wildlife
Once digging had stopped plants recolonised the reserve, creating wildflower grasslands, willow scrub, marsh and reed beds. At the water’s edge live flowers such as the damp-loving Gypsywort (Lycopus europaeus), Southern Marsh (Dactylorhiza praetermissa) and Common Spotted Orchids (Dactylorhiza fuchsii), and Water Mint (Mentha aquatica).
The shallow pools create ideal conditions for dragonflies and damselflies, which appear from midsummer onwards. Eighteen species of dragonfly breed on the lake. The bright Common Blue damselfly (Enallagma cyathigerum) is one of the most numerous of these delicate insects, but you will also see the Blue-tailed (Ischnura elegans) and Emerald damselflies (Lestes sponsa). Dragonflies, such as the powder-blue Black-tailed Skimmer (Orthetrum cancellatum), zoom across the surface of the water.
It is the only site in Gloucestershire (it is only just over the county border) where the rare Brown Hairstreak butterfly (Thecla betulae) lays eggs on the Blackthorn hedge(Prunus spinosa).
The first summer bird visitors arrive at Swillbrook in April – warblers such as the Chiff-Chaff (Phylloscopus collybita), Sand Martins (Riparia riparia) and Swallows (Hirundo rustica) following soon after. By May birdsong rings out from the willow scrub – the scratchy song of the Sedge Warbler (Acrocephalus schoenobaenus) fighting for attention with those of the Reed Warbler (Acrocephalus scirpaceus), Blackcap (Sylvia atricapilla) and Willow Warbler (Phylloscopus trochilus). From the thick hedges comes the lovely song of the Nightingale (Luscinia megarhynchos).
Water birds such as the Great Crested Grebe (Podiceps cristatus), Coot (Fulica atra) and Mallard (Anas platyrhynchos) all nest around the lakes.
At the end of summer, Hobbys (Falco subbuteo) gather to feast on dragonflies, Sand Martins and Swallows.
The first winter visitors, the ducks, start to arrive in October. The drakes have finished moulting, and their plumage is looking its dazzling best, to attract a mate. Mallard (Anas platyrhynchos) and Gadwall (Anas strepera) are regulars – but listen out for the whistling call of the Wigeon (Anas penelope). In the deeper areas, Pochard (Aythya ferina), Tufted Duck (Aythya fuligula) and Goldeneye (Bucephal) can be seen diving, and if you’re really lucky you might see the striking Goosander (Mergus merganser).
History and Management
Swillbrook Lakes was riverside meadow before being dug for sand and gravel in the 1960s. The method of extraction left the lakes fairly shallow, the lake beds uneven, and the site was not worked right up to the edges, leaving shallow pools and spits of land protruding into the water.
The site, owned by the Hills Group, was left virtually untouched until the Trust took over its management. Now it is a case of maintaining the variety of habitats and preventing the area from reverting to willow scrub.
Other information
Dogs are allowed, but must be on a short leash at all times of year.
Best time to visit: Midsummer onwards for dragonflies and damselflies, and any time of year for the bird life. If you wish to extend your walks into Clattinger Farm it’s best to go in late April for Snake's-head Fritillary (Fritillaria meleagris) to the end of June for hay meadow flowers (hay is cut in July).
Habitat: Lakes, ponds, wetland, grassland, hedgerows.
Specialities of the reserve: Dragonflies, water birds, Brown Hairstreak.
Location: Travelling north on the A419 Swindon - Cirencester road, turn left onto the Cotswold Water Park Spine Road. After crossing the B4696 South Cerney/Ashton Keynes road, take the next left, Minety Lane, after about 1.5 miles. Parking is in the gateway on either side of the road, after about 0.5 miles. Swillbrook Lakes nature reserve and information board is on the east side of the road at grid reference SU018934.
