Fen
Fen is the first stage in the natural change, or succession, from open water to woodland. Fens are waterlogged areas of land dominated by reeds, rushes and sedges, and they form a complicated system of plant and animal communities.
Although there has been a significant loss of fen to woodland since the early 1900s, there are still around 5000 hectares of undrained peatland in the Broads. Currently about 1700 hectares of this consist of open fen, while the remaining area is covered with scrub and carr woodland. This amount of open fen means that the Broads is home to the largest expanse of species-rich fen in lowland Britain.
Wildlife of the fens
The Broads fens support a diversity of plant and animal species with over 250 different plant species present, many of which cannot be found anywhere else in lowland Britain. The fen orchid and crested buckler fern are two rare examples.
Another important plant of the fens is ragged robin, which along with meadow thistle provides a vital food source for the adult swallowtail butterfly. This is Britain's largest butterfly, which is restricted to the wetland habitat of the Broads. The caterpillars feed on milk parsley, which is abundant in the fens but scarce outside East Anglia.
Fens are home to a host of other rare species. Many species of dragonfly and damselfly can be found hovering over dykes and turf ponds, including the rare Norfolk hawker, our emblem. The dykes themselves are often packed with water plants, such as water soldier, bladderwort and frogbit.
The swallowtail butterfly is chief among numerous butterflies that are to be found in the fens of the Broads. There are also many moths including rare species such as the reed leopard and Fenn's wainscot, and hundreds of other invertebrates including beetles, flies and spiders.
Three species of bird are particularly associated with the Broads fens, the bittern, bearded tit and marsh harrier. Bitterns were once a regular occurrence, but Victorian egg collectors and 20th century deterioration in water quality and fen habitat resulted in a dramatic decline in numbers.
We have been involved in two partnership projects to restore habitats for the bittern. The first is situated at East Ruston Fen and the second more recent project is on land adjacent to How Hill National Nature Reserve on the River Ant; this is known as Buttle Marsh. Other birds such as the marsh harrier have made a successful comeback in response to improved fen management in recent decades.
Fens are also home to a variety of mammals. Water voles frequent the dykes, and many other species of small mammal live and nest within the fens, such as harvest mice and water shrews. Larger mammals such as red deer and Chinese water deer also frequent the fens, along with increasing signs of otter, following reintroduction efforts by the Otter Trust at Earsham.
