Wildlife and Conservation Review of 2000
The Environment Agency has been monitoring fish populations in the Thames for many years, to
investigate changes in response to pollution control measures. In July, Sea Lampreys were confirmed
as breeding, the first modern breeding record of this BAP species. The tidal Thames now supports
some 118 species of fish, although the lamprey is only the seventh known to be spawning at the
present time, following from Dace, Smelt, Sand-smelt, Sole, and Common and Sand Gobies.
Another tantalising record was the discovery of a late-instar nymphal Mole-cricket at South Woodham
Ferrers in a garden where it had been molested by the dog. On investigation, there was no further
evidence of this cryptic, almost-extinct species in the garden, but neither was there any obvious
means of introduction. It is suggested that there may be an as yet undetected colony on one of the
nearby damp, grassy EWT or Essex County Council reserves. The specimen came to light as part of
an English Nature Species Recovery Project, which also received reports of song from Dagenham
Chase (which may have been a Grasshopper Warbler), and an adult found in a Southend street. The
latter is assumed to have been introduced via the nearby greengrocer's shop.
A related order to the Orthoptera is the Dermaptera, or earwigs. Despite the ubiquity of at least one
species, the group is much-overlooked, as John Widgery demonstrated when he recorded Short-
winged Earwig new to each of five 1km squares he passed through on a short walk around Great
Saling. But of course it is not only insects which can be overlooked: Zoe Ringwood noticed a yellow
Umbellifer on the verge of the A120 at Horsley Cross, on the way to her study site for Fisher's
Estuarine Moth, a specialist feeder upon Hog's-fennel. On investigation, it turned out to be just that,
Hog's-fennel, some 40 plants of it, several kilometres inland of its known sites, seemingly but not
surprisingly without its lepidopteran specialities. What is particularly remarkable to me is that I
must have driven past that road verge hundreds of times a year for the past ten years!
Another species that could easily be overlooked is the Small Red-eyed Damselfly, the discovery of
which was reported last year. In July, three new sites were reported in the Bradwell area, which sadly
triggered a mass twitch involving unacceptable behaviour from a minority of observers. It was also
noted at Hadleigh Castle and Bedfords Park, Romford, and by September in the Lee Valley. The first
British record from outside Essex also came during 2000 from the Isle of Wight. It would seem that
establishment and expansion is taking place, which fits with its recent history on the Continent, but
it is perhaps likely that part of the 'expansion1 is due to observer-awareness of the species and its
occurrence in Britain.
Amazingly, Bradwell also produced an Essex first during July, a Lesser Emperor dragonfly.
Although only a recent addition to the British List, Lesser Emperor now seems to be of annual
occurrence, and the Essex record came as part of a widespread and substantial influx. Just prior to its
discovery, a 'real' Emperor dragonfly came to the Bradwell moth light, indicative of migratory
movement taking place. Indeed such movement seems to have been on a very broad front, as around
that time, both Emperors were recorded new to Ireland. So despite, or perhaps because of, the
unsettled weather Bradwell performed well for migrant Odonata and indeed for immigrant
Lepidoptera: it was considered that but for poor trapping conditions, it could have proved to have
been one of the best seasons ever, albeit truncated rapidly by autumn rains.
Bradwell has the biggest trap, and so gets the best and most moths, aided by its coastal location,
open vistas, and its position as an oasis amid an arabic desert. But it doesn't have a monopoly on
migrants. The fact that good records can come from any part of the county is demonstrated, for
example, by the mid-July record of Bedstraw Hawk-moth from Felstead. And then a week later a
probable Nine-spotted moth was photographed in the Clacton area. Its generic identification was
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Essex Naturalist (New Series) 18 (2001)