A bumble bee with nearly full pollen baskets/sacs. A pollen sac or a pollen basket, are on the hind legs of some bees. When collecting pollen, they store it in their sacs to bring back to the hive....thus, the more pollen they collect, the more filled their baskets become. It takes visiting between 50-100 flowers for a bees basket to be filled. A pretty cool fact about a bees pollen basket is that you can tell the sex of a bee, by their basket. Female bees are pollinators, so they will have pollen sacs, whereas the male bees don't have pollen baskets.
Tracy Evans Photography 2014