Transcript

The wetlands of Wicken Fen

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NARRATOR

The wetlands of Wicken Fen-- Britain's oldest nature reserve. Some 7,000 different species of mammals, birds, plants, insects, and other invertebrates have been recorded here, making this one of the most biologically diverse places in the UK. Why is Wicken Fen so rich in species? What is the relationship between habitat diversity and species diversity? And what role does conservation play in promoting biodiversity at this very special reserve? Wicken Fen, this is one of the last surviving fens in Western Europe. For much of the year, this low-lying land is waterlogged, creating the unique fen environment of waterways, marshes, meadows, and woodland.

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A remnant of the great fen that once covered six and a half thousand square kilometres, Wicken Fen is situated in Eastern England, just below The Wash in the county of Cambridgeshire. Today, 99.9% of what was the great fen has been replaced by farmland, and Woodwalton, Holme, Chippenham, and Wicken are the only remaining areas of fen. Wicken Fen, though it covers less than 4 squarer kilometres, is now the largest fen in the region. A nature reserve for just over 100 years, the fen is home to a tremendous diversity of species. Near the woods, a herd of deer, one of the fen's 29 mammal species, graze the scrub. Among the grasses and wildflowers of the fen meadows, Ringlet butterflies flutter, one of a thousand species of butterflies and moth recorded here. There are 200 species of bird on the fen, including reed warbler. Counting all of the different species of Wicken Fen, including animals, plants, and fungi, is one way of determining its level of biodiversity.

JOANNA FREELAND

Biodiversity is a contraction of the terms biological and diversity, and it basically just refers to the number of species and the number of individuals within each species, living within a particular place and a particular time. The easiest way to measure biodiversity is just to go out and count, first of all, how many species there are and second, how many individuals there are within each species.

NARRATOR

But biodiversity is more complex than just a headcount. It's influenced by a number of factors. One of these is the range of habitats within an area. A habitat is an environment in which a species, be it plant or animal, can live.

JOANNA FREELAND

Within the UK, Wicken Fen would definitely be considered to be a biodiversity hotspot. There's an estimated 7,000 species of insects, plants, mammals, all other different types of taxa at Wicken Fen. And of course, going along with that, there's a huge range of different types of habitats.

NARRATOR

The open water is just one of many habitats at Wicken, each with its own characteristic species. Because Wicken is a fen, its multiplicity of habitats depends in part on moisture levels. The wettest areas are the waterways, ditches, and ponds. These contain aquatic plant species like water lilies and pond weeds.Adjacent to these areas are shallow waters which are suitable for reeds. In areas where these waters dry in summer, fields of sedge dominate. Dryer again are the fen meadows, which are home to wildflowers and grasses. Dryer areas may also be covered by woodland and bushes, like birch and gelder rose. In terms of biodiversity, habitat and species are closely linked to each other.

JOANNA FREELAND

The more habitats that you have within an area, the more species, as a rule, you will find within that area. That is because, for the first part, habitats are defined, to a fairly large extent, by the species living within them.