Bees with a skunk stripe?

[Psparr]

Went through my hive the other day and noticed that about 1% of the bees had a white stripe of hair on their thorax.
Just wondered what's going on?
Thanks in advance.

[deknow]

They are foraging on jewelweed.

deknow

[Psparr]

You may be right, but its a perfectly shaped stripe on each bee?

[Spear]

I have a few bees in my hives with yellow stripes on thier backs - pollen?
Tried to get a pic but is rather out of focus: