Bombus humilis Illiger,1806

Description and notes

Keys and general biology are found in Sladen (1912), Free & Butler (1959), Alford (1975) and Prŷs-Jones & Corbet (1991). This species is very closely related to Bombus muscorum but is more southerly in its distribution. B. humilis has undergone a major decline in its distribution, with most remaining populations being on extensive, although sometimes narrow, areas of coastal grasslands. This decline seems to be closely linked to the intensification of farming.

  • Photo by Robin Williams
    Bombus humilis worker
  • Photo by Nick Owens
    Bombus humilis worker on kidney vetch, Kenfig, Wales, July 2011
  • Photo by Steven Falk
    Bombus humilis male. Rye N.R. Sussex
  • Photo by Jeremy Early
    Bombus humilis worker, Kent
  • Photo by Robin Williams
    Bombus humilis var illiger male; Stoborough Heath, Dorset, July 1998. GR SY9845
  • Photo by Nick Owens
    Bombus humilis worker on kidney vetch, Kenfig, Wales, July 2011
  • Photo by Steven Falk
    Bombus humilis male. Rye N.R. Sussex
  • Photo by Steven Falk
    Worker Bombus humilis
  • Photo by Nick Owens
    Bombus humilis worker on red clover, Castlemartin, Pembrokeshire, July 2011
  • Photo by Steven Falk
    Bombus humilis male. Rye N.R. Sussex
  Pre 1980   1980-99   2000 and later

The following datasets are included:

  • Bees, Wasps and Ants Recording Society - Bees, Wasps and Ants Recording Society - Trial Dataset

Distribution

Intermittently present along the southern and western coasts of England and Wales, reaching furthest north on the Lleyn Peninsula and Anglesey. There are a few inland populations, most notably on Salisbury Plain, Wiltshire. In common with other bumblebees, relatively large areas of suitable habitat, in the order of ten square kilometres, are required to maintain viable populations. Widespread in Europe, as far north as southern Scandinavia, but declining in many places (von Hagens, 1994; Westrich, 1989). Also found throughout central Asia (Løken, 1973).

Status (in Britain only)

This species is not listed in either Shirt (1987) or Falk (1991). However, current research shows that this status may be in need of revision.

Habitat

Strongly associated with areas of tall, but open, grasslands supporting a good proportion of perennial plants, especially those in the families Fabaceae, Lamiaceae and Scrophulariaceae.

Flight period

Overwintered queens search for nesting sites during May and early June. Workers fly between June and September; males during August and September.

Pollen collected

There is a strong preference for pollen from plants from the families Fabaceae, Lamiaceae and Scrophulariaceae.

Nesting biology

B. humilis queens found nests on the surface of the ground in moderately tall, open grassland. They may well use an old mouse nest as a base. The nest is covered with fragments of dead grass and moss which are gathered, initially by the queen and later by the workers.

Flowers visited

The species will forage for nectar at a variety of plants, including yellow Asteraceae.

Parasites

Bombus (Psithyrus) campestris has been recorded as a social parasite of this species in mainland Europe (Løken, 1984).

Author of profile

M Edwards.