Wildlife and Conservation Review of 2001
found one on Meadow Vetchling, possibly the first record from this foodplant. And further
south, the Essex Heath Fritillaries again produced a second brood, albeit not as large as that in
1999 (there were none in 2000).
During August in particular, it became clear that we were in the midst of an outstanding natural
phenomenon - the widespread colonisation of the Small Red-eyed Damselfly (see plate 9). The
discovery in Essex of this as a new British species, and its subsequent spread, have been discussed
in the past two Essex Naturalists, but this summer the spread and assumed colonisation continued
apace. While numbers declined somewhat at the original sites, it appealed in often large numbers at
many new sites, especially ou the coast (eg Dovercourt, Holland Haven, Fingringhoe Wick). It was
also found for the first time in Norfolk. The timing and location of new records is suggestive of at
least partial re-immigration this year, and as yet there is no definitive proof of breeding, although
that will surely corne.
Pam and Peter Wilson continued their excellent survey of Essex borrowdykes, this year focussing
upon the Crouch area. No really good saline lagoon-like sites were found, although a group of
dykes on the north bank provided not-inconsiderable interest: Littorina saxatilis tenebrosa,
considered by some to be a good species, and not found previously in the Essex survey; Gammarus
insensibilis (RDB3 and specially protected under the Wildlife & Countryside Act 1981), found at
just one site previously at Beaumont, was located in a rather unpromising ditch next top an arable
'prairie' - presumably a relict population which may be heading for extinction; Berosus spinosus,
an RDB3 beetle was found for the third time in the survey (earlier records were at Langenhoe and
Tollesbury); and the RDB2 soldier fly Stratiomys longicornis, which was found in several sections.
The Crouch and Dengie area appears to be a national stronghold for this dramatic species.
But others didn't need even to get out of bed to make interesting observations. In mid-August, near
Maldon, Simon Wood was kept awake by the loud trilling song of what was clearly a cricket. When
captured, its identification caused some problems, due to its macropterous form, but eventually the
balance of opinion suggested it was a Southern Field Cricket Gryllus bimaculatus. We must
assume that it was an escape or introduction: it is a species which is often kept in captivity for
reptile food. It was captured and remained alive for a further two months, but at least in the garage
its vocal exploits were kept bearable. Another good record, this time botanical, also came to light
when David Baker found between 200 and 400 plants of Small Teasel in the Colne Valley at
Pebmarsh, a significant new population of this scarce species.
By now, return bird migration was in full swing, sometimes spectacularly so, such as reports
early in the month of Swifts moving south over Walton at a rate of more than a thousand an hour.
Seabirds included counts of 36 and 41 Black Terns at East Tilbury and Barking respectively, and
a Pomarine Skua and 3 Sabine's Gulls were off Bradwell. Continental drift migrants included
Honey Buzzards at Fingringhoe Wick and Colne Point, and conceivably a Red Kite at Old Hall,
while passerines from a similar vector included Wrynecks at Gunners Park and Bradwell, and a
Barred Warbler at Hainault. From the other side of the pond, the Wilson's Phalarope remained
at Old Hall until 18th, and a Pectoral Sandpiper was at Vange Marshes. And among the more
staple fare, the waders produced good counts of 5 Wood Sandpipers at Colchester Hythe, 27
Green Sandpipers at Vange, maxima of 27 Whimbrel, 402 Avocets and 650 Ringed Plovers at
East Tilbury, where there was also a very early report of 2 Hen Harriers on 27th.
Some positive conservation news was the re-establishment of a grazing flock at Blue House
Farm, following the FMD cull, but it is sad to report that the sheep suffered almost immediately
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Essex Naturalist (New Series) 19 (2002)