The Fens would have been home to huge populations of waterfowl and fish. The enthronement feast of the George Neville Archbishop of York in 1466 gives an indication of the diversity and abundance of waterfowl
that the fen habitats of the time would have supported. The feast included 204 Cranes, 400 swans and 400 herons, 4000 mallards and teals, 204 bitterns and 1000 egrets! Throughout the middle ages eels were so plentiful that they were used as rent!
Today less than 1% of the original fenland habitats remain in fragments across the Fens. Nevertheless these remnant wetlands still support an exceptional diversity of wildlife. There are sites in the Fens that are of International, European and National importance for example; Wicken Fen and Woodwalton Fen. A recent biodiversity audit of the Fens catalogued over 13,000 species. For some of these, such as the Fen Ragwort, Marsh Carpet Moth and Fen Violet, the Fens are one of their last strongholds. The Fenland Flora project is mapping the distribution of the entire vascular flora and characterise the plant assemblages.
The wetland nature reserves of the Fens are important for wildlife. However the arable ditch network is home to some important species of aquatic plants and insects and the farmland itself is a key stronghold for declining species of farmland bird such as turtle dove, corn bunting, tree sparrow, grey partridge and yellow wagtail.
Conservation organisations such as the RSPB, the Wildlife Trusts and the National Trust have ambitious plans to increase the amount of wetland habitat in the Fens which are already starting to yield dividends. In 2007 cranes returned to breed at Lakenheath Fen for the first time in 400 years. The organisations also work in partnership with farmers to increase rare farmland bird populations on their land.
The future for the wildlife of the Fens is looking bright again!