Archive for August 1st, 2019
Monthly Science: Organ Pipe Mud Dauber Emergence
An industrious pair of Organ Pipe Mud Dauber Wasps assembled their nest last August:

Their offspring began emerging in early July, with our first picture on 3 July. I’ll leave the image file dates in place so you can reach your own conclusions:

We think a titmouse (a known predator) pecked some holes, including the upper hole on the middle tube, as they seemed to expose solid (and presumably inedible) chitin from the outside:

More holes appeared in a few days:

The irregular spacing along each tube suggests they don’t emerge in the reverse order of installation:

Three days later:


Two weeks after the first holes appeared:


No more holes have appeared since then, so it seems one young wasp emerges every few days.
This nest produced about a dozen wasps, with perhaps as many launch failures. We’ll (try to) remove it and examine the contents in a few months.
We expect they’ll start build nests all over the house in another month …
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