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SPIDERS IN WALTHAMSTOW MARSH, MEETING ON 6TH JUNE 1992
Despite a very poor forecast, the weather turned out tobe much better than expected, but conditions
were far from ideal for finding spiders. The pretty Theridion pictum was found to be numerous along
concrete fencing and on scrub nearthe river. This is a rare spider in Essex but it is also found near Enfield
by the River Lea in similar circumstances and it looks as though the Lea Valley could be quite a
stronghold for the species.
Various spiders characteristic of marshy and scrub habitats were found including the uncommon "money"
spider Baryphyma pratense and orb-web spider Zilla diodia, but most species were widespread and
common.
An abundance of Russian Comfrey on the Marshes was extraordinary and possibly ofsome concern. It
may indicate the degree to which thearea is drying out and gradually losing its marsh flora. Nevertheless
Walthamstow Marshes are evidently of great interest and it is quite remarkable to walk into them from the
adjacent traffic and noise and built up area of East London.
Peter Harvey
BEAUTIES VANISH IN THE DROUGHT
(Southend Evening Echo, Friday June 19th 1992)
A lack of clean, well oxygenated water is threatening Essex's colourful dragon flies and damselflies. And
when they decline, there are fears forthe futureofthecounty'sother wildlife. From 33 species in the 19th
century, there were only 25 in 1990, The emerald damselfly is almost extinct.
The longest drought for more than 150 years, followed by a series of hot summers, has accentuated the
water shortage and increased demand for water abstraction after decades of land drainage, damage to farm
and village ponds and the conversion of grazing marshes for arable crops.
There is also the problem of water pollution. Dragonflies are sensitiveto pollution from chemicals,
pesticides and herbicides and to enrichment caused by run-off of fertilisers and sewage.
Essex Wildlife Trust spokesman Brian Watts said: "Most dragonfly species require pollution -free, well
vegetated water in which to lay their eggs. After hatching the young spend from one to four years in the
water before emerging as free fly ing adults. Both the adults and the nymphs are ferocious predators. The
nymphs take small crustaceans, water fleas, small worms, tadpoles, small fish and other insects. In turn a
wide variety of birds prey upon dragonflies as well as some spiders. Consequently a site rich in dragonflies
indicates a site rich in wildlife."
● 1989; The trust acquired a reserve on the Thames Marshes with a rich dragonfly fauna. The drought
of 1990 dried out the marsh and few dragonflies have been seen since.
● 1989: Slurry effluent turned 10 miles of the River Roding from a clear river with dancing insects and
flashing kingfishers into a sewer lined with 30,000dyingfish.