|Leafcutter bee on Ragwort|
Pollen carried by honeybees and bumblebees is visibly quite obvious. Both have become extremely adept at packing their pollen loads carefully, and neatly, into the smooth, widened pollen baskets (corbicula) situated on the sides of their hind legs. Once the pollen is packed in, very little is likely to fall off - and what does fall off is not viable anyway. With these bees, it is the pollen that sticks to their body hair that helps pollinate flowering plants.
Solitary bees are less fastidious. They collect pollen on 'scopa'; stiff, branched hairs, located on their legs, under their abdomens, or along the sides of their bodies. As the female solitary bee collects pollen, she packs it onto her scopa less carefully, and without the addition of saliva to moisten it. This means it is far more likely to fall off when the bee visits the next flower....which in turn means the next flower is more likely to be pollinated.
|Bombus terrestris (Buff-tailed bee) on Buddleia|
|Halictus rubicundus female|
This image shows the pollen collecting hairs of the ground nesting bee 'Halictus rubicundus' BEFORE pollen collection. Note how hairy her legs are.
Most cavity nesting solitary bees, like the Leafcutter bee pictured here, collect pollen on their abdominal scopa. This method of collecting pollen is extremely messy and is one of the reasons why some Mason bees (close relatives of the leafcutter) are around 100 times more efficient as pollinators than honeybees.
So, there you have it. Solitary bees are in fact the unsung heroes of the pollinating world!
N.B. There are a few solitary bees that, unusually, carry pollen back to their nests in their crops.
Bumblebees and honeybees are, of course, also wonderful pollinators, but in different ways and for different reasons. More about this another day….