Freshwater Life
Recorders: M.W.Hanson, G. Wilkinson, S. Wilkinson, Pam Wilson, Peter Wilson,
Sheila McDonald, Dr Peter Hammond, the late Stan Hudgell, Derek Smith
Records:
2000 - 2003
Hylands has a good range of freshwater habitat - with at least fifteen ponds of varying size, an
ornamental serpentine lake - almost certainly the work of Humphry Repton - three areas of flowing
water (River Wid, Sandy Brook and the culvert), a Ha-Ha ditch, a "moat" (at least a deliberately
excavated linear/curved feature), a watercress bed (spring-fed) and "sedge-fens" - areas of very
wet ground colonised by the sedge Carex pendula. Many of the ponds contain Great Crested Newts.
Not all the water bodies are permanent (ie the Ephemeral Pond), some al least partially dry-out in
summer. Even so. the tiny Ephemeral Pond is probably the oldest in the park and has a unique flora
and fauna (including Fine-leaved Water-dropwort and the damselfly Lestes dryas) and really merits
further investigation and special conservation measures. The flowing water habitat obviously lias
its own specially adapted species; the culvert and Sandy Brook probably suffer from some polluted
run-off from adjacent agricultural land. The River Wid, running extensively through agricultural
land, is also vulnerable to pesticide and fertiliser run-off, but still prov ides for Water Vole, Otter,
the damselfly Platycnemis pennipes and the local (RDB 3) Bryozoan Lophopis crystallina, which
was recorded (as statoblasts in flood debris) from here in 2002. The Ha-Ha ditch south of the house
is notably the home of the rare land leech Trocheta subviridis.
HYDROZOA
Hydra viridissima
Hydra vulgaris
TRICLADIDA
Dendrocoelum lacteum
Dugesia lugubris
BRYOZOA
Lophopis crystallina
MOLLUSCA
Acroloxus lacustris
Ancylus fluviatilis
Anodonta anatina
Anodonta cygnaea
Gyraulus albus
Gyraulus crista
Hippeutis complanatus
Lymnaea palustris
Lymnaea peregra
Lymnaea stagnalis
Musculium lacustre
MOLLUSCA cont.
Physa acuta
Pisidium personatum
Planorbarius corneus
Potamopyrgus antipodarum
HIRUDINEA
Glossiphonia complanata
Glossiphonia heteroclita
Helobdella stagnalis
Theromyzon tessulatum
Trocheta subviridis
MALACOSTRACA
Asellus aquaticus
Asellus meridianus
Crangonyx pseudogracilis
Gammarus pulex
EPHEMEROPTERA
Baetis vernus
Cloeon dipterum
Essex Parks: Section 2 - Hylands Park
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