Experience in Rearing Common Carder Bees (Bombus pascuorum Scop.), with Some Notes on Three Similar Species: Shrill Carder Bee (B. sylvarum L.), Red-shanked Carder Bee (B. ruderarius Müll.), and Brown-banded Carder Bee (B. humilis Ill.) (Hymenoptera: Apidae)

Abstract

The rearing method under controlled conditions known for Bombus terrestris was successful in initiating egg-laying for 83% of B. pascuorum queens. After larvae had hatched, fresh pollen pellets needed to be inserted into brood pockets daily. After the first workers had emerged, colony development was advanced by placing them outdoors and supplying them with a sugar solution and pollen. The bees were able to use tightly pressed pollen from small plastic pots inserted near the brood. This feeding resulted in large colonies that produced dozens of young queens. In contrast, colonies managed in the laboratory were unable to utilize pollen in a similar manner. They raised only a few workers and several queens. Mating young queens was easy. It was stimulated by daylight, but in the case of B. humilis by direct sunshine. Several B. pascuorum and B. sylvarum queens were overwintered and began the new generation under artificial conditions. However, a lack of fresh pollen limited the development of colonies outside of the vegetation period.

Trialling techniques for rearing long-tongued bumblebees under laboratory conditions

“…Rearing conditions, such as nest box design and pollen type, have a substantial effect on the health and reproductive success of bumblebees reared in captivity. There is some evidence to show that giving young, long-tongued colonies access to flowers allows natural foraging and improves colony development (Lhomme et al 2013;Ptáček et al 2015;Moerman et al 2016). Many of the long-tonged bumblebees can be characterised as pocket makers, feeding their larvae a solid rather than liquid diet (Den Boer and Duchateau 2006).…”

“…Providing brood has a stimulatory effect on queens of several bumblebee species (Yoneda 2008;Bučánková and Ptáček 2010), and cocoons of B. terrestris have commonly been used in rearing trials of long-tongued species (Kwon et al 2003;Bučánková and Ptáček 2012;Ptáček et al 2015). Allowing cocoons to hatch and callows to remain in the colony, or adding B. terrestris or Apis mellifera callows, can also have a stimulatory effect on queen egg-laying and B. pascuorum and B. ruderarius are at least somewhat encouraged to oviposition by honey bee workers (Ptacek 1983(Ptacek , 1985Ptáček et al 2015). Callows have also been observed caring for the queens own brood; Ptáček et al (2015) observed B. terrestris workers feeding B. pascuorum and B. sylvarum larvae.…”

“…Allowing cocoons to hatch and callows to remain in the colony, or adding B. terrestris or Apis mellifera callows, can also have a stimulatory effect on queen egg-laying and B. pascuorum and B. ruderarius are at least somewhat encouraged to oviposition by honey bee workers (Ptacek 1983(Ptacek , 1985Ptáček et al 2015). Callows have also been observed caring for the queens own brood; Ptáček et al (2015) observed B. terrestris workers feeding B. pascuorum and B. sylvarum larvae. However, in another trial, B. hortorum queens were aggressive towards multiple stimuli and have been observed destroying B. terrestris cocoons and killing honey bee workers (Bučánková and Ptáček 2012).…”

“…This sometimes involves an excluder, which keeps queens physically separated in a shared nest box. Once they are placed together, one female usually becomes dominant and begins egg-laying (Ptáček et al 2015). Ptácek et al (2000) and Ptáček et al (2015) found queen pairing effective for B. pascuorum but not for B. humilis or B. ruderarius , who displayed 'resentful' and aggressive behaviours.…”

“…Once they are placed together, one female usually becomes dominant and begins egg-laying (Ptáček et al 2015). Ptácek et al (2000) and Ptáček et al (2015) found queen pairing effective for B. pascuorum but not for B. humilis or B. ruderarius , who displayed 'resentful' and aggressive behaviours. Of the three B. humilis females they trialled, one broke through the excluder to reach and kill her neighbour.…”