The picture winged fly Dorycera graminum (F.) (Diptera, Ulidiidae) in South Essex
HARVEY. P. (2000) The East Thames Corridor: a nationally important invertebrate fauna under threat.
British Wildlife 12 (2): 91-98.
ISMAY (2000) The status, distribution and biology of Dorycera graminum (Fabricius) (Diptera, Ulidiidae).
English Nature Research Reports, No. 395.
STUBBS, A. (1997) Wildlife reports: Flies. British Wildlife 8 (3): 190-192.
Bumblebees in Essex in 2001
TED BENTON
13 Priory Street, Colchester CO1 2PY
Restrictions due to Foot & Mouth Disease (FMD) severely restricted fieldwork, especially in the
early part of the season, but special attention was paid to the more localised Essex species where
fieldwork was possible.
Bombus jonellus
The first confirmed Essex sighting of this species was a female observed at White Clover Trifolium
repens on Old Hall Marsh RSPB Reserve on 20/06/00 (Benton 2000a,b). The species is strongly
associated with Heather heathland, but some literature sources also mention coastal habitats. Searches
to determine the status of the species at Old Hall or elsewhere in Essex were clearly a priority of
2001. Unfortunately Old Hall was inaccessible, but a visit to Frinton on 12/06/01 yielded a brief
sighting of what was very probably this species at Bird's-foot-trefoil Lotus corniculatus by the
path between the sea wall and the golf course. On a subsequent visit (20/07/01) a single female of
B. jonellus was photographed on Black Horehound Ballota nigra, also on the path by the golf
course. Numerous similar individuals were caught and checked, but all turned out to be Bombus
hortorum. Owing to the superficial similarity of these two species, it is quite possible that B. jonellus
is under-recorded in the county. It emerges from hibernation and establishes its nests early, as does
B. pratorum, and, also like that species, generally has two generations in a single season. B. jonellus
should be looked for in coastal or heath-land sites. The short face and reddish corbicular hairs
distinguish the females from those of B. hortorum.
Bombus muscorum
There is considerable national concern about the decline of this species, and a clear case for its
inclusion on the list of Biodiversity Action Plan species. Again, FMD restrictions hampered searches
in 2001. In Essex, this species is so far known only from remaining grazing marshes and sea walls
along the cast coast, where it is very dispersed, and present in small numbers. Holland Haven
Country Park, and the edge of Frinton Golf Course seems to be the main Essex strong-hold, significant
numbers being seen there in July 2000. Three visits were made in 2001. On 12/06/01 none were
seen. On 20/07/01, 3 or 4 workers were observed on Tufted Vetch Vicia cracca along the edge of
the golf course. However, the large grassy expanse on the seaward side of the Country Park had
been close-cut, eliminating all forage sources for B. muscorum, and none was seen there. By contrast,
on 17th and 18th July 2000, as many as eight workers on each occasion had been seen foraging on
tufts of flowering Vicia cracca in this area.
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Essex Naturalist (New Series) 19 (2002)