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The Bee That Sleeps Hanging On

The Bee That Sleeps Hanging On

If you spend a summer afternoon near a patch of lavender or salvia in many parts of Australia, you may notice a bee that does not look like the honey bee in picture books. It is about the same size, but it darts rather than drifts, and its abdomen is striped with bands of shimmering blue. This is the blue-banded bee, one of more than 1,500 kinds of native bee found in Australia.

Unlike honey bees, blue-banded bees do not live in hives. Each female works alone, digging a burrow into a soft clay bank or crumbling mortar and building a row of small cells at the end of it. In every cell she leaves a ball of pollen and nectar and lays a single egg; then she seals the cell and moves on. She will not meet the young bees that hatch from it.

The bees have a talent that honey bees lack. Some flowers, including those of tomato plants, hold their pollen tightly inside narrow tubes. A blue-banded bee grips the flower and vibrates its flight muscles rapidly, shaking the pollen loose in a small cloud. Scientists call this 'buzz pollination', and researchers have been studying whether these bees could help pollinate tomatoes grown in greenhouses.

At dusk, the males do something even more surprising. Instead of returning to a nest, they gather on a thin stem or a dry grass stalk, clamp on with their jaws, and fold their legs up against their bodies. Several males often share the same stem, and some return to that spot night after night, hanging there until the morning warmth wakes them.

The best way to see them is to plant blue or purple flowers in a sunny spot and to be patient. They visit each flower quickly and rarely stay long, so a gardener who looks away for a minute may miss them entirely.