(^102) an environmenTal hisTory of Wildlife in england
conditions. The first was erected, at Sutton St Edmund in Lincolnshire,
in 181751 : by 1852 J. A. Clarke estimated that whereas there had once been
around 700 drainage windmills between Cambridge and Lincoln, the same
area was now served by a mere 17 steam engines, which collectively drained
upwards of 222,000 acres (90,000 hectares).^52 Drainage was improved still
further in the course of the nineteenth century through further refinements
in drainage technology including the adoption of light ‘grasshopper’ steam
engines, and (from the 1850s) of Appold’s centrifugal or turbine pump. By
the 1870s, around 75 per cent of the East Anglian Fenland was under the
plough. Many of the fields were tile-drained, and the ‘soak’ of acid water in
the ditches was permanently kept down to a level which would not injure the
growing crops. In place of wet grassland, and ditches brimming with water,
the Fens had attained their modern appearance: arable fields, filled with
wheat or potatoes, extended to the far horizon. Only scattered fragments of
undrained fen survived. Babbington described in 1860 how ‘With the water
many of the most characteristic plants have disappeared, or are become
so exceedingly rare that the discovery of single individuals of them is a
subject of wonder and congratulation’ among botanists. He believed that
with the exception of Wicken Fen – which still survives as an important
nature reserve – ‘there is scarcely a spot remaining... in which the ancient
vegetation continues undisturbed’. Even the ‘absolutely aquatic’ plants had
suffered, because many of the drainage ditches now dried out completely
in the summer.^53 Such a landscape could not sustain the vast flocks of birds
which had once thronged it. Richard Lubbock in 1847 described how ‘oats
are grown where seven or 8 years back one hundred and twenty-three Snipes
were killed in one day by the same gun’. Upcher in 1884 voiced similar
sentiments, commenting that ‘The ‘trips’ of Dotterell (Eudromis morinellis),
formerly so regular in their appearance, are now scarcely ever seen in our
fen country’.^54 The bittern, thought Stevenson in 1885, was ‘another of the
birds which drainage and enclosure has driven from their old haunts’.^55
There were similar declines in invertebrates, with the large copper butterfly,
once a common sight in the Fens, disappearing entirely from the area by the
start of the twentieth century: it now hangs on in only a few places in the
Norfolk Broads.
When drained wetlands lay under pasture the height of the water in the
dykes, as we have seen, was kept artificially high throughout the year, almost
at the level of the adjacent land. The margins of the dykes are thus poorly
defined, trampled and muddy. When ploughed, in contrast, water levels are
kept lower and the ditches are given a steep-sided ‘v’ shaped profile and
have margins with smaller areas of mud and a less well-developed marginal
vegetation. The old form of dyke margins would have been an important
resource for a very wide range of invertebrates, including Anopheles, the
mosquito host of the parasite Plasmodium, the carrier of malaria. The loss
of this pest from the landscape by the later nineteenth century represented,
in a strict sense, a reduction in the nation’s biodiversity. The fact that it is
elle
(Elle)
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