Essex bumblebee report 2002
TED BENTON
13 Priory Street, Colchester COl 2PY
The queens of all six of the common bumblebee species (Bombus lapidarius, lucorum, terrestris,
pascuorum, hortorum, and pratorum) were out of hibernation by the last week in March. A worker
of B. pratorum was seen on 20th April in Colchester, and workers of B. lucorum at Frinton, as well
as the first female of the common 'cuckoo' bumblebee, B. vestalis, on the same day. May 4th brought
sightings of the first workers of B. lapidarius, B. pascuorum and B. hortorum, on Clacton 'cliffs'.
Here, too, a brief 'battle' between a queen B. hortorum and a female of its 'cuckoo', B. barbutellus
was observed, with the latter eventually giving up and flying off. A female of B. campestris, a
'cuckoo' of B. pascuorum, was also seen on the same date, foraging on Dandelion Taraxacum sp.
Finally, May 4th was also the first (and unusually early) date for newly emerged males of B. pratorum.
On 10th May the first B. terrestris workers were seen in a garden at Frinton, as well as the first male
of B. hortorum, in the Holland Haven Country Park. On the 25th May males of two 'cuckoo'
bumblebees (B. sylvestris - a social parasite of B. pratorum - and B. campestris) and a melanic
female of B. campestris were seen at Hilly Fields, in Colchester. Also on 25th May, at the Buntings
Nursery site, adjacent to Hilly Fields, I saw the first of very few Essex specimens (one worker and
a rather faded queen) of the localised and declining B. ruderarius observed this year. June 1st
brought the first observations of males of three further species: B. lapidarius, B. vestalis and B.
terrestris, at Holland Haven.
A further queen of B. ruderarius was noted feeding on Bramble Rubus fruticosus agg. in High
Woods Country Park (Colchester) on 2nd June, and a male B. barbutellus was seen on Marsh
Thistle Cirsium palustre on H illy Fields a day later. A visit to Copt Hall (National Trust) yielded a
few sightings of worker B. muscorum (the Moss Carder-bee, now listed as a Biodiversity Action
Plan species), and one very worn queen. This species appears to have been lost (possibly temporarily)
from its former stronghold at Holland Haven Country Park: hay cutting in late July may be responsible
for the demise of nests before they reach maturity, by eliminating late-flowering forage-sources.
The most exciting bumblebee event of the year took place later that month. The so-called Large
Garden Bumblebee Bombus ruderatus was on the original Biodiverstiy Action Plan list, but little
serious study had been devoted to it due to failure to find a breeding population anywhere in the
UK. Since 1985 there had been only four reliable reports of isolated individuals in Essex. However,
in 2002, Mike Edwards and Paul Williams were alerted to populations of this bee in the Nene and
Ouse Washes, further north in East Anglia. It was suggested I go to one of the sites to obtain
photographs, which I did on 19th June. On 22nd June, John Dobson and I were recording dragonflies
along the sea-wall just to the west of Jaywick when I was astonished to see a male B. ruderatus
foraging, along with some half-dozen B. muscorum workers on a patch of Red Clover Trifolium
pratense. A subsequent visit, on 26th June, confirmed the presence of both males and workers of B.
ruderatus between Jaywick and Bel-Air, on sea walls and adjacent rough ground, and, further west,
around Lee-over-Sands and Colne Point. Further studies of the Essex populations of this rare species
will be reported next year. Small numbers of workers of B. muscorum were observed along the sea
wall and the adjacent track between Jaywick and Colne Point. Meanwhile, the first males of B.
lucorum had been observed on 23rd June.
Essex Naturalist (New Series) 20 (2003)
51