Text Meelis Uustal
Photos Tiit Jürisson
Cuckoo bumblebee / Bombus rupestris / with ”vermin”
When studying summer photos of bumblebees sometimes light brown bumps on the bumblebees catch attention. They are mites, eight-legged relatives of spiders and ticks. While the first thought is that surely these creatures suck the vitality out of bumblebees it is not true of many mites living with bumblebees. The mites themselves cannot fly at any stage of their life. Because of this they cling to bumblebees to get a free ride into the bumblebee nest. There however they act as domestic workers, destroying rubbish generated in the nest.
Since a bumblebee nest perishes every autumn the mites would die of starvation staying in the nest. So they grab firmly on to bumblebees and hope to arrive into a new living place. The mites even winter together with young female bumblebees. If this talk about the usefulness of these mites is not convincing then maybe the knowledge that on the selfsame cleaner mites even smaller mites may be busy is consoling ...
Another harmless feeder on the waste of the bumblebee nest is a member of the silken fungus beetles (Cryptophagidae) – a beetle. It waits for the bumblebee on a flower. It grabs and holds hard on to the bumblebee and does not let go until the bumblebee, having conceded defeat, carries it into the nest. There it too can start its cleaner’s life. Friendly as well as harassing subtenants are surprisingly numerous in the bumblebee nest and so bumblebees in one more way, besides pollinating, support the biodiversity of species.
As said not all the creatures living in the bumblebee nest are friendly. For instance the hoverfly Volucella bombylans has already been introduced LINK
Parasitic mites live too on bumblebees, residing in the airways of the bumblebees – they are certainly not good for the bumblebees. The cuckoo bumblebees cannot be left without mention either – we will talk soon about their strange life.
Cuckoo bumblebee with vermin“
On what flowers have you seen bumblebees in action this year? Note the species on the bumblebee web form and help gaining new knowledge about the distribution of bumblebees in Estonia!
Identification forms for bumblebees : LINK
Bumblebee web questionnaire: LINK
Join the „Meie kimalased – Our bumblebees” group on Facebook: LINK