This was one of several bees (see accompanying post) seen flying agitatedly around a small area of holes in the sand. The holes were near the shore of a marine estuary, and seemed just barely above the highest tide-line...perhaps being inundated at times.

These bee's behavior made them seem like cuckoos (or perhaps males seeking females to mate with?). Rather than directly enter a hole; they'd circle, hover, land, and tentatively poke in a bit. Then they'd quickly scurry into the hole, remain for a few seconds, and scurry back out. Afterwards they'd immediately repeat this sequence at a nearby hole (i.e. without any pollen-foraging trip in between).

A strange thing is the holes seemed too close to the level of tidal inundation for a "responsible bee mom" to set up a nest for provisioning eggs/larva. And who's ever heard of an "irresponsible bee mom"? (Other than cuckoos of course ;-) Then again, it's possible the mother bees were ignorant of the tidal dangers...or more likely, I'm speculating off track!

The holes looked like they may possibly have been formed by sand crabs, familiar to all (at least California) beachgoers from the bubbling holes they leave as a wave recedes along a beach.

At any rate, I'd love to know the ID of this bee; and will appreciate any illuminating comments about it's behavior.