Wildlife and Conservation Review of 2001
Probably the most important insect discovery though was in the unlikely location of some
' wasteground' in an industrial area in Colchester. The area was subject to a planning application
for redevelopment, so Jerry Bowdrey checked it out, having heard that Bee Orchids were known
from the site. He duly found them, and much, much more. Among the insects found over the next
few weeks was a bug new to Britain collected by Peter Harvey and determined by Dr Peter Kirby
as Orthocephalus tenuicornis, although a male would be desirable for certain identification; the
RDB3 Blue Carpenter-bee; more than 30 scarce or local invertebrates; together with a colony of
Common Lizards. Most exciting was the discovery of the wasp Cerceris quadricincta, a nationally
endangered species included in the UK Biodiversity Action Plan. Eventually its nests were located
in a hot spot at the base of a wall - the only known breeding site in Britain. The site lent itself to
an autecological study by Peter Harvey, who was able to identify its food items, mostly common
weevils which live on Gorse, Hawthorn, herbaceous legumes, docks and willows. Using this
information it was possible to begin discussions towards safeguarding the species within the context
of the proposed development. Much of the assumed foraging area is likely to be lost, but the
development proposals have now been modified to include a newly-created foraging site.
Only time will tell whether this is successful. One interesting observation is that no protected
invertebrates were found on the site, and the only legal protection which can be applied is in
relation to the occurrence of the much commoner but protected ' Common' Lizard. A further point
of interest is that the Colchester area seems to be a hotspot for Cerceris: Peter Harvey found two
further individuals on the Middlewick Ranges. And as a final point, this nesting site again shows
the immense invertebrate importance of so-called 'brownfield' sites.
Turning now to vertebrates, a Bottle-nosed Dolphin penetrated the Thames into the heart of London,
although, as is so often the case, it was later found dead at Wapping, and confirmed as an adult,
some 3.5m in length. A little less dramatic perhaps, but no less noticeable (apart from the security
surrounding the site) a strong colony of Marsh Frogs was reported from Langenhoe Marsh. Although
apparently known from the site in the past, this was the first time they came to more general notice:
the habitat is consistent with other long-established populations at Romney Marsh, Kent, and
Hadleigh Marsh, although its mode of introduction is not known.
Breeding birds were also a feature of Langenhoe. Bearded Tits bred for the first time in several
years, there were three Marsh Harrier nest involving 2 males, which produced 7 young, and there
were two pairs of Avocet and one of Garganey. Such breeding events may be a dividend from the
FMD outbreak, as military activity was severely curtailed on the site. Another pair of Marsh
Harriers was present further up the Colne (but the nest was preyed upon by a Fox), and there were
others around the Walton Backwaters, but with no evidence of breeding. Woodcock were confirmed
breeding in Norsey Wood for the first time in 20 years, and surveys at Hadleigh Castle Country
Park showed significant increases in breeding populations of waders and Skylarks. Any or all
of these breeding successes may be attributable the access restrictions, leading to reduced human
and dog disturbance, especially during the crucial phase of territorial establishment during the
spring. Perhaps this indicates the true potential of our normally crowded countryside, and the
ability of birds in particular to respond quickly to changed circumstances: 'disasters' often have
their up-side. Take also the record wet conditions of last autumn. This led to fewer winter cereal
sowings, and there seems to have been something of a concomitant increase in seed-eating birds.
In general terms though, BTO data showed that the breeding season was relatively poor for
resident birds in particular. Compared with 2000, national data indicated a 43% decline in Blue
Tit productivity, and other serious productivity declines in Long-tailed Tit (37%), Blackbird (33%),
Dunnock (23%) and Moorhen (15%). It is suggested that the mild winter encouraged early breeding,
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Essex Naturalist (New Series) 19 (2002)