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Flower-rich herbage which develops a tall (~1/2m) sward in late summer is important
Although there may be areas of abundant Odontites at the sides of paths, the bumblebee seems
to prefer flying at the level of Odontites where there is also taller vegetation. The presence of a
previous abundance of clovers and other species such as Lotus appears to be significant.
The presence of scrub may be important
At both Wat Tyler C.P. and Benfleet Downs C.P. there are large areas of scrub adjacent to the
flower-rich areas containing the Odontites and other forage plants. At Ferry Fields there were
formerly areas with hawlhorn scrub which were uprooted a few years ago (causing quite a local
uproar and in which the Local Authority responded by putting an emergency Tree Preservation
Order to try to slop further clearance). The uprooted scrub was left in place and gave rise to
areas protected from grazing which developed taller herbage. The ground disturbance caused by
this work may have encouraged the development of areas of abundant Odontites found in 1994
when B. sylvarum was numerous at the south-western end of this site. At Broom Hill there is
some scrub and hedging on the site and in nearby areas.
The presence of scrub at or near all the areas where the bumblebee has been seen may be
important for nest sites or may simply be due to the fact that these arc the areas which have been
managed to provide the best flower-rich herbage.
Scrub edge may be important because it provides protection of nest sites from disturbance or
provides small mammals with protected nest sites, especially where adjacent grasslands are cut
or grazed in spring or summer. Scnib edge which lias been cut to prevent scrub invasion may
provide the conditions favoured by Odontites and so these are the richest forage areas in August.
Continuity of forage sources throughout the season is important
Plentiful sources of nectar and pollen throughout the season are likely to be important. The fact
that this species starts nesting later than most other bumblebees and that nests only consist of
few individuals is likely to make the species particularly vulnerable to loss of forage sources.
Forage success during August, when many long corolla tube flower sources are over, may be
very important in order for the bumblebee to produce enough workers and resources to ensure
successful reproduction.
References
ANON., 1980. Atlas of the bumble bees of the British Isles. International Bee Research Association and
the Biological Records Centre, Huntingdon, England.
HARVEY, P.R., 1998. Biodiversity Action Plan bumblebees, Essex 1998 report. Unpublished.
PHILP, E.G., 1998. Species account and map of British distribution of Bombus sylvarum (Hymenoptera:
Apinae). BWARS Newsletter, Spring 1998: 28.
Essex Naturalist (New Series) 16 (1999)