Yellow Pollen Stripe on Bee's Thorax

My friend Janice bought two full hives in May.

She was new to beekeeping and hadn't taken the beekeeper's course yet so I offered to help her with her first hive inspection.

Her hives looked great and she was proud to hear that her queen was an awesome layer. There were wall to wall worker combs on the frames.

With both hives we noticed the occasional worker with a strange rectangle shaped yellow stripe on their back (thorax). It was a yellow daffodil colour and to my thinking it didn't look like pollen.

It was such a perfect rectangle with such straight edges that it looked like it had been painted on. Was it some strange infection I wondered? Were the bees sick with something? Janice wondered if she'd medicated them incorrectly.

I regret very much that I didn't take photos of these striped bees but at the other photos are of Janice and her bees.

There was only one thing to do: Ask an expert.

I emailed our tech team and they advised that there are certain flowers that mark the bees with this stripe.

That was a relief to hear!

I've been reading The Biology of the Honey Bee by Mark L. Winston (I'll report on this book later). In it he says that when bees groom themselves they "have a blind spot on the top of their middle thoracic segment, and workers returning from pollen-collecting visits to certain flowers can be seen with a stripe of brightly colored pollen on that region of the thorax."

It's so nice to have double confirmation. It'd be nicer if I had pictures too… next time I will.