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The Swale National Nature Reserve Introduction Situated at the south-eastern end of the Isle of Sheppey, the Swale National Nature Reserve forms part of the internationally recognised coastal marshlands of north Kent. The reserve's saltmarshes, grazing marshes, creeks and mudflats provide feeding and roosting areas for large numbers of wildfowl and waders. It is managed by English Nature. The
Reserve The reserve largely consists of marshland which
can be separated into two types: grazing marsh and saltmarsh (salting), the
latter being occasionally flooded with seawater during spring tides and
generally left ungrazed. At low tide extensive mudflats are revealed which,
together with the marshland, attract considerable numbers of ducks, geese and
wading birds. Ten species of wildfowl regularly nest on the reserve in the
spring, and large flocks of waders including oystercatcher, curlew, redshank,
knot and dunlin, can be seen during the winter months. At that time of year
you may also chance to see flights of linnet, twite, greenfinch and the
occasional Lapland bunting - on the very edge of its northern range. A total of
over 200 bird species have been recorded on the reserve. At the eastern end of the reserve lies Shellness
where a spit extends into the Swale channel. Such a feature is formed by
longshore drift of beach material, which in this case is largely composed of
cockle shells, washed up from the extensive cockle beds off Whitstable. The
shell spit is still gradually continuing to extend in a south-westerly
direction. Once the sand and shell shingle forming the spit has stabilized, it
becomes colonised by a distinctive group of plants including the attractive
yellow horned-poppy and viper's bugloss. Below the beach at Shellness
Point, a vast area of muddy foreshore can be seen at low tide. Hidden
just beneath the surface of the mud is a wealth of small marine invertebrates
which form the staple diet of many waders. Some of these animals occur in
amazing numbers; the shrimp-like crustacean Corophium, for example, can reach
densities of over 50,000 per square metre! The preferred food of the dark-bellied
brent geese, however, is eelgrass. Up to 1500 of these birds may arrive in early
winter from Siberia to feed on the extensive eelgrass beds growing close to, the
low watermark. Eelgrass, incidentally, is the only British flowering plant able
to grow submerged in the sea. Moving inland, ungrazed saltmarshes are found
between the mudflats and the sea wall. The dominant plant here is cord
grass, though lots of smaller grasses can be
seen
growing beneath, such as saltmarsh grass and sea arrow grass. In the summer
months, the flowers of salt-tolerant species such as sea-lavender, sea-purslane
and thrift may also be seen. These saltmarshes are also the main site in Britain
of the rare ground lackey moth. Its eggs can withstand both saltwater and
dessication, and the caterpillars, which emerge in early summer, form silken
tents amongst the saltmarsh vegetation. The marshland on the inland side of the sea wall
is carefully managed to provide a number of different habitats, and so maintain
diversity of wildlife found in the reserve. It is grazed by both cattle and
sheep, some of the marsh fields being grazed the whole year round, some being
winter-grazed, and some being left ungrazed. The ungrazed grassland is favoured by short-eared
owls, hen harriers and many breeding wildfowl, as the long blades and tussocks
of grass hold large numbers of rodents and give good cover from nest predators.
Both slow-worms and common lizards may be seen basking in the sun on the sea
wall in summer, but grass snakes prefer the damper ditch edges to the drier
rough grassland. In spring when the cattle are taken off the
winter-grazed areas, the grassland assumes a kind of broken tufted effect.
Waders like snipe, redshank and lapwing breed here. Small mammals and insects
are numerous because of the varied structure of the grass. The all-year-round grazing area is the preferred
feeding ground for ducks, geese and waders, particularly around the wetter areas
after stormy winter weather. Waterfowl find it easier to graze on the shorter,
more regular swards because of the structure of their bills. There is, of
course, little cover on an area like this for small mammals or breeding birds. The marshland is intersected by many freshwater
ditches, although these tend to be
slightly brackish. Marsh frogs are common in the ditches, and plants characteristic of
slow-moving water such as ivy‑leaved duckweed and thread-leaved water-crowfoot
can be found together with those tolerant of more brackish conditions such as
sea club-rush and the rarer tasselweeds. Many birds feed here and several
species including reed warbler, sedge warbler, yellow wagtail and gadwall breed
in the nearby flooded marsh areas. Rabbits are numerous and concentrate around
the drier earth mounds, believed to be medieval salt-workings. Unusually, jet
black individuals occur. In midsummer, commonly seen butterflies include
gatekeeper and painted lady together with the Essex skipper, a species
restricted to coastal areas of south-east England. Several species of brightly
coloured dragonflies can be seen darting and hovering over the ditches too. The reserve is managed in a way that ensures
different parts of the marshland remain suitably wet. This is done by controlled
flooding of the four main marsh fields on
a
rotational basis. The fields are surrounded by one metre high
earth walls called bunds which serve to trap rainfall and raise surface water levels, thereby providing shallow
floods for the benefit of water birds.
Ditches
allow for excess water to be drained from one field
to another by means of adjustable sluices.
The flooded areas are rotated,
with
a different one of the four sites flooded each year, and in
this way the quality of the grassland is
maintained. If additional water is
required,
it can be pumped up from a borehole situated at the
western
end of the public footpath. A visitor route is provided around this area of
rotational floods, where good views
can
be obtained from the observation hides. Financial aid for
the bunding scheme was provided by the Council to the
Commission of the European Community. Access There is a footpath along the top of the sea
wall from Shellness hamlet to Sayes Court from where excellent views of the saltings and grazed marshes can be
obtained. Access to the observation hides on the flood areas is signposted from
the sea wall footpath. The circular route is 3km (about 2 miles) long and
rejoins the footpath 1km (about 1/2 mile) further on. Entry to the remainder of
the reserve is by written permit only, obtainable from the English Nature regional
office. At Shellness you may walk to the shell beach
along the path at the edge of the saltings, and along to the
point, keeping the yellow posts to your left. Please do not stray from
the path or make too much noise as you will disturb roosting, feeding or nesting
birds on the beach and on the saltings. You are welcome to use the wartime
blockhouse as a hide to watch the birds. The hamlet of English Nature The Countryside
Management Centre
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