Here in Cornwall, the milder weather has encouraged some brave bumblebee queens to emerge from hibernation and take advantage of the early-flowering plants here. While we do have some winter-active Buff-tail colonies here, most bumblebee queens have been tucked up underground in a long winter’s sleep awaiting Springtime. While in Summer a queen bumblebee proudly secures a nest of up to several hundred individuals, her first few weeks after hibernation are in fact spent solitarily. During this time she ensures a suitable nest site, sets out on foraging expeditions and begins her role as a mother. All whilst battling with Spring’s uncertainties, of course!
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A queen Early bumblebee (Bombus pratorum) on Lesser
Celandine, one of the first bumblebee species to emerge
from hibernation.
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As
the Spring sun warms the soil, bumblebee queens in their underground burrows
start to stir. Here, a queen bumblebee has spent around seven months tucked up
in the earth awaiting the Spring alarm. After warming up and with a morning
stretch of all six legs, this determined queen eagerly digs her way out of her
little burrow, dusts the soil off her coat and sets off into the fresh Spring
air to begin the first of her very busy days.
After
this long sleep, she is feeling hungry rather than refreshed. She has spent the
last several months relying on her energy reserves and her first thought is to
find nectar-rich flowers. At this time of year, flowers may be few and far
between, but dandelions or a lucky garden find of Mahonia or heather should do
the trick. Once revived, a clean of her proboscis and pollen-dusted eyes, she
can now begin her next search for a suitable nest site.
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Left to right: Red-tailed (Bombus
lapidarius), Tree (Bombus
hypnorum), Early (Bombus
pratorum) and
Buff-tailed
(Bombus terrestris) queens.
Queens here have been found foraging on crocuses, dandelions and lesser
celandines.
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She
spends considerable time zig-zaging around, searching diligently for a
promising site. Depending on her species, she may take a fancy to an old rodent
burrow, tussocky grass if she is a Common Carder (Bombus pascuorum), or even an empty bird box if she is a Tree
Bumblebee (Bombus hypnorum)!
Following
a queen Early Bumblebee (Bombus pratorum),
we see her finally decide on an old rodent burrow. While it’s a ramshackle
affair of cobwebs and darkness, it provides just what she needs with nesting
material conveniently left behind by the previous occupants. She rearranges the
material with her little jaws and legs to form a very snug hollow ball, with a
single entrance just large enough for her to pass through. In this cavity, she will
create a mass of ‘pollen-paste’, made up of pollen and nectar that she has
collected on her foraging trips.
Having
decided on her home she will set off to explore her new neighbourhood, excitedly
flying to and fro and exploring every nook and cranny. She is in fact familiarising
herself to its location to ensure that she can return swiftly after her
foraging trips. After a few practice flights, she now knows the way to her new
home.
During
these foraging trips, she battles with the uncertainties of Spring. While the
air may be clear and sunny when she leaves, she often returns to her nest with
a very soggy, matted coat. Nevertheless, her hind legs are stuffed with pollen
and she quickly resumes to the task of constructing her nest. Having mated the
previous Autumn, she lays her first batch of eggs upon this ‘pollen-paste’ mass
and seals off the structure with wax, which is in fact only around the size of
a pea!
Just
like birds, she too incubates her brood day and night. This
energetically-demanding task requires a lot of nectar. To prevent her from
leaving her brood for too long, she cleverly crafts a small wax pot in front of
her and fills this with regurgitated nectar. She sips from this while she
incubates her brood, replenishing her little pot when necessary.
After
a few days, these eggs will hatch into very hungry larvae. As the larvae
greedily eat, the queen replenishes this pollen and distributes a mixture of
nectar and pollen amongst them. Once fully grown, the larvae will then each tuck
themselves up into a cocoon. The cocoons are arranged such that there is a
groove that fits perfectly with the queen’s underside. By stretching out her
abdomen and hugging all six legs around her cocoons, she ensures their continual
warmth for the next few weeks before her brood are ready to bite through their
cocoons as adults.
Their
movements hesitant and much like a baby’s first steps, the first of her workers
are out. Once they have found their feet (all
six of them!), they will fulfil their role as baby bee guardians and take over
the collection of nectar and pollen to bring back to the nest. However, the
queen’s work isn’t over yet – she has a colony of workers to build!
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Charlotte Rankin is an ecologist with a passion for bumblebees that embraces both research and conservation. She is a volunteer for the Cornish branch of the Bumblebee Conservation Trust and last year she created two booklets for the conservation group, Penryn Buzz to promote their Bee Ranger project. She has also helped the charity Buglife in establishing their Urban Buzz project in Falmouth. You can follow Charlotte on Twitter at, @bumble_being |
