Wildlife and conservation review 2003
Although the peak of the breeding season, June still produces some exciting migrant birds, and this
year's tour de force was on the 16th, when a warbler was found at Fishers Green in the Lee Valley
Initially identified as a Marsh Warbler, its true identity as Essex's first Blyth's Reed Warbler was
not revealed until photographs were critically examined later in the day. A Kentish Plover was at
the Naze all month, and other late (or early?) migrants included Red-backed Shrike (Tollesbury
Wick), Red-footed Falcon (Old Hall), Long-tailed Skua past Bradwell, Osprey (Stour Wood) and a
Corn Crake seen (!) at Rainham. 7 Crossbills were seen at Weald Park, and up to 11 Red-crested
Pochard frequented Hanningfield Reservoir (a feral origin is most likely for these). Most impressive
though was the total of 51 Mediterranean Gulls between Westcliff and Shoebury on the 25th, at
the same time as a huge build up of 150 further south at Dungeness.
For most of July, the weather simply got better - sunnier and hotter, with several days exceeding
30°C. Large numbers of Meadow Brown, Gatekeeper and skipper butterflies enlivened every road
verge, and a White Admiral turned up at Marks Hall, a new site and a natural addition to the
butterfly community re-establishment programme. In the latter half of the month, more Painted
Ladies appealed, even more numerous than earlier in the year. Presumably these represented the
offspring of the earlier primary immigrants, and contributed some remarkable counts, such as Dave
Owen's estimated 5000+ at Marks Hall on the 29th.
Moths too responded well to the weather. Many typical midsummer species were on the wing some
two weeks earlier than in 2002, and some rare occurrences included Dusky Hook-tip at Skipper's
Island (the fourth Essex record) and two Tree-lichen Beauties, new to the county. Most amazing
was an event led by Jon Clifton in Stour Wood on the 18th. Twelve light haps were deployed, and
the final tally amounted to 252 species (of which 81 were new to the site). This easily constitutes
the best night ever at any site in Essex, and has rarely (if ever) been surpassed elsewhere in the
UK. Clearly the search effort played some part, but surely as much as anything it is due to the
excellent management of the site by the RSPB.
Finally on the insect front, as the month progressed, so the frequency of macropterous Roesel's
Bush-crickets increased. Despite their rather ungainly appearance in flight, this is the form adapted
for dispersal, one which is produced preferentially when population densities are high, which in
turn is most likely to occur in a warm summer.
The Southend Mediterranean Gulls increased to at least 90, including colour-ringed birds from
the Czech Republic and the Netherlands. Nearby, the Fleet Head Little Egret roost peaked at 78,
while a Great White Egret was again in the Abberton and adjacent coastal area, and 3 Spoonbills
were seen at Manningtree. Typically, wader movements took off during the month: a Temminck's
Stint was at Old Hall, an early Curlew Sandpiper at Colchester Hythe, and 35 Black-tailed Godwits
seemed a little out of place on Dagenham Chase. A Gull-billed Tern was reported past Shoebury,
and a Honey Buzzard over Epping, while a post-breeding group of 9 Black-neeked Grebes on
William Girling Reservoir was notable. At Hanningfield, breeding was confirmed among the Red-
crested Pochard; equally dubiously, Hamford Water held two Ruddy Shelduck, though their arrival
date would fit with the likely timing of birds displaced from their breeding areas in south-east
Europe and the Middle East as their shallow waters dry out.
Also in Hamford Water, it proved a good breeding season for Common Seals, with 11 pups seen
(although two were later found dead on the Dovercourt beaches); in contrast, most Black-headed
Gulls at the site failed to fledge as a result of very high tides at the crucial times. At the other end
of the county, fish sampling by the Environment Agency at Tilbury Power Station added a new
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Essex Naturalist (New Series) 21 (2004)