Osmia bicolor is one of the first bees of spring, emerging as early as February in their native range of South England and Wales. As solitary bees, there are no queens and workers; females build their nests alone. Males emerge, mate, and then die.
What makes these little bees so captivating is where they make their nests. They repurpose empty snail shells, belonging to a small group of bees known as “helicophiles” (snail-lovers). As a single mom, letting a snail do all the construction work for a home seems much more sensible than building your own from scratch.
It is the fussy nesting behavior of these bees that makes them so delightful to watch. Here is a female arranging her nursery shell just so; it wouldn’t do to have the opening pointing upwards and letting in rain.
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