Mare Fen Local Nature Reserve

This 17 hectare site is a large expanse of permanent pasture lying in the floodplain of the River Great Ouse used for summer grazing for cattle or sheep.

Grassland like this was once common in the Ouse Valley, but the reserve is now one of the remaining precious fragments. The wet meadows contain a mosaic of grassland types complemented by reed fringed ditches and ponds.

The water levels are controlled using sluices and overflows. During the winter the sluices are open to allow the fen to flood and closed late spring for grazing.

Habitat type

Wet grassland meadow, ditches.

Grid Reference

TL 366 698

Conservation Status

• Local Nature Reserve
• County Wildlife Site

Wildlife

When flooded in winter, this reserve is excellent for birds, providing much needed shallow water for over-wintering waterfowl and wading birds.

Mare Fen is a great place to see wildfowl such as mute swan, wigeon, teal, shoveler, tufted duck and snipe.

During the spring and summer a range of aquatic plants flourish. Dragonflies, frogs, toads, newts and grass snakes can be found around the ponds and ditches. Badgers are known to take advantage of the soft ground to forage for worms and muntjac can be seen grazing.