Colours - _TNY_8026
This little fuzzball on a very pink milkweed (Chamaenerion angustifolium) is a four-coloured cuckoo bumblebee (Bombus quadricolor). Now, let's break that name apart and see what we can figure out:
For starters, it looks more like it has three colours than four - black, yellow and orange. So it must be a Bombus tricolor, right? Wrong. B. tricolor is a (beautiful) North American species and this one is in Härnösand, Sweden (which isn't in North America). The fourth colour happens because the orange hue is in fact a blend of red and white hairs.
There is a very similar, non-cuckoo bumblebee called the early bumblebee (B. pratorum), but that one has clear wings while this like all B. quadricolor have dark wings.
Continuing with the name, "bumblebee" is pretty straight-forward - but what about the "cuckoo" part? Well, cuckoo bumblebees are parsitic. Notice that this one doesn't have the pollen baskets on the hind legs that normal bumblebees do. That's because instead of gathering their own pollen, cuckoos take over nests of another species, and this species parasitises on the broken-belted bumblebee (B. soroeensis).
The distribution for this species has shifted over time and it really can't be found in the the southernmost parts of Sweden, but have instead expanded north. and it has decreased all over Europe. Estimates have it that between 25 and 50% of the total population is in Sweden now.
Colours - _TNY_8026
This little fuzzball on a very pink milkweed (Chamaenerion angustifolium) is a four-coloured cuckoo bumblebee (Bombus quadricolor). Now, let's break that name apart and see what we can figure out:
For starters, it looks more like it has three colours than four - black, yellow and orange. So it must be a Bombus tricolor, right? Wrong. B. tricolor is a (beautiful) North American species and this one is in Härnösand, Sweden (which isn't in North America). The fourth colour happens because the orange hue is in fact a blend of red and white hairs.
There is a very similar, non-cuckoo bumblebee called the early bumblebee (B. pratorum), but that one has clear wings while this like all B. quadricolor have dark wings.
Continuing with the name, "bumblebee" is pretty straight-forward - but what about the "cuckoo" part? Well, cuckoo bumblebees are parsitic. Notice that this one doesn't have the pollen baskets on the hind legs that normal bumblebees do. That's because instead of gathering their own pollen, cuckoos take over nests of another species, and this species parasitises on the broken-belted bumblebee (B. soroeensis).
The distribution for this species has shifted over time and it really can't be found in the the southernmost parts of Sweden, but have instead expanded north. and it has decreased all over Europe. Estimates have it that between 25 and 50% of the total population is in Sweden now.