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Wildlife and Conservation Review of 1999
Country Park and Benfleet Downs, still held the bee, though apparently in lower numbers than in
1998. Importantly, new sites, both supporting substantial numbers, were located on Canvey Island
and at East Tilbury. Its supposed association with Red Bartsia is clearly not obligatory as the plant
was not present at the latter site: the main pollen source appeared to be Narrow-leaved Bird's-foot-
trefoil Lotus tenuis. At both sites, Lotus was most frequent next to motorbike scrambling tracks,
demonstration that a degree of disturbance is not always a bad thing. Observation of foraging behaviour
also suggested a difference between the workers of Bombus sylvarum and B. humilis - sylvarum
seemed to forage largely on Lotus in longer swards, whereas humilis seemed more catholic in its
choice.
While searching for Bombus sylvarum at Wat Tyler CP, Jerry Bowdrey recorded an attractive leaf
beetle Sermylassa halensis on Lady's Bedstraw; this beetle is local in Britain, and there was only
one previous recent Essex record. Closer to home, and proof that naturalists don't always have to
travel far in search of interesting quarry, Jerry Bowdrey and Jerry Heath noticed a colourful beetle
on the windowsill of their laboratory at Colchester Museum. It was identified as Metoecus paradoxus,
a parasite on wasp larvae, and so presumably originating from a wasps' nest in the roof cavity.
Another very exciting discovery was of the Scarlet Malachite Beetle Malachius aeneus at Clavering
(and also in Hertfordshire), by Peter Hodge as part of an English Nature-funded project. Once
widespread, though local, this is now classed as rare and is a BAP priority species: the reasons for its
decline are as yet unknown. Pam and Peter Wilson's survey of the brackish-water fauna of our
borrowdykes continued apace, and they turned up new sites for three key protected species - Starlet
Sea-anemone Nematostella vectensis. Lagoon Sea-slug Tenellia adspersa and Lagoon Sand-shrimp
Gammarus insensibilis - along with the uncommon mudsnail Hydrobia neglecta at several locations.
The botanists too were out and about - Drooping Brome Bromus tectorum was found new to north-
east Essex in Bathside Bay on the Stour Estuary. Man Orchid at Little Sampford, and a putative
hybrid between Common Spotted and Greater Butterfly Orchids at West Wood. Tim Pyner
located Narrow-leaved Ragwort Senecio inaequidens at both Canvey and Rainham, and Hartwort
at Broom Hill, thus boosting the latter species' claim to native status. Two of the unusual plants
reported last year from the A13 at Purfleet, Clustered Bellflower and Large Thyme, also turned up
at Fisher's Green; the suspicion now must be that these may be unrecorded introductions, like the
Dropwort which was found in Grays Chalk Pit. If people insist in adding to our flora, we would at
least like to know about it, as they could produce interesting ecological observations. Never a rare
plant Common Ragwort had an exceptional summer, much to the consternation of graziers around
the county. It is an important plant for many insects, but it is accepted as a problem species in many
meadows and pastures (although the origin of the problem is often mis-management of the grassland).
As an alternative to spraying, weed-wiping or hand-pulling, English Nature helped to develop a
mechanised 'eco-puller', to allow environmentally sensitive control without huge labour
implications.
Hog's-tennel has long been renowned as one of the special plants of north-east Essex, as some 60%
of the UK population is found there, and also as this is the only locality which supports the rare
Fisher's Estuarine Moth. A late summer survey for English Nature by Terri Tarpey produced up to
date distribution maps and abundance estimates, and served to highlight the incredible importance
of just two sites which together support 92% of the Essex Hog's-fennel and 96% of the British
Fisher's Estuarine Moth.
At least one pair of Marsh Harriers, as first reported in May, were successful in rearing a brood of
four chicks in an inaccessible part of the north-east coast. Avocets too had a successful season, with
Essex Naturalist (New Series) 17 (2000)