Your garden hosts the lonely blue bee rock concert
Scientists have recorded blue-banded bees head-bopping and shoulder-popping at three hundred and fifty times a second. The move is called ‘buzz pollination’, and it affects us more than we realise.
Blue-banded bees break many bee stereotypes. In fact, the first time I saw their blue blur whizzing around the garden, I had no idea what insect they were. They’re quite stout and move similar to a hover fly. Facing the unknown, I did what any self-respecting scientist does – I took to Google.
Turns out that I relate a lot to these little guys (definitely sans the dancing, but we’ll get to that). They’re one species of about two thousand Australian solitary bees. To compare, there’s only ten social bee species living in hives. The females burrow into soft mud or sandstone to make their nest, and the males… I’m not exactly sure why nothing eats them, but they snooze on branches like a bunch of grapes. They look ridiculous. You can tell the difference between them by counting stripes – four for females, five for males. Much like myself, they also rumoured to be attracted to the colour blue, and are non-aggressive. They won’t sting unless they’re under attack – and that means attack by inspecting fingers too!
Upon finding a flower with delicious pollen, the blue-banded bee grips the protruding stamen with it’s legs and curls it’s thorax around it. Then things start to get interesting. Bees, and many insects, have asynchronous muscles. This type of muscle is not like our own, which tenses or relaxes with a single nerve signal. Instead, they continue to tense and relax long after a signal – enabling their wings to beat at high speeds.
As seen above, those muscles driving the wings disengage and convert to the head-banging action which releases the pollen. Rock on, little guy.
At first it seems like this is all a bit excessive. I mean, I sure don’t shake the fridge to make a sandwich. And neither do most bees. There’s only a handful that buzz pollinate. So why do they?
If you scratch my back, I’ll buzz yours
This is a case of the classic gunslinger stand-off. A mutualistic relationship, where both species need something from the other to survive. The bees need protein and fats from the pollen for themselves and their offspring; the plants need bees to deliver their plant sperm (pollen) to the girl next door. So it benefits the plant if the bees are more specialised, such that they only visit a few species. For some Australian natives, buzz pollination is the only way to get to the pollen.
Home growers and farmers alike benefit from a visiting buzz pollinator. In America this is the bumblebee, but Australia doesn’t yet have a commercialised species. Tomato growers currently rely on hours of manual labour with a mechanical vibrator (you heard me right). And it doesn’t even do a good job. Trials have shown a 20% fruit weight increase when using blue-banded bees instead. What’s more, is that they might be better workers than the bumblebee. They spend less time on each flower, tend to visit other plants more often, and can buzz at higher speeds.
It’s predicted that 20,000 flowers could benefit from buzz pollination. Besides tomatoes, many common fruit and vegetables are included. Blueberries, cranberries, kiwifruit, chillies, and eggplant all hide their pollen. The clever blue-banded bees could be the alternative farmers need.