Getting the builders in

We should all wish for contractors like these.

Yellow-legged Mud-dauber Wasps, Sceliphron cementarium, were diligently collecting mud from small puddles in an abandoned rock quarry near me. They would spit into the mud, and push it together into a tiny ball (by her front left legs):

in their enthusiasm they go head-down in the mud:

Once it was formed into a nice ball:

they clutch it to their abdomen, and fly off:

I tried but failed to get a mid-air shot!

I never found their nests, but a similar technique is used by the Catskill Potter Wasp, Ancistrocerus catskill, who used her mud to sculpt two of these tiny edifices in the corners by my back door.

They are destined to be the sarcophagi for paralyzed sawfly larvae, onto which the wasp lays an egg, after which she seals the whole thing up.

The egg will hatch into a larva which will then feed on the sawfly larva, pupate, and emerge as an adult wasp.

Now that the next generation was fully incarcerated, I was trying to decide whether to slice it open to inspect the contents, when something unexpected happened.

The wasp built an addition, and poking out of it was a tiny grub.

Then the wasp herself appeared, all 1/2″ of her, dangling a paralyzed grub of some kind as food for her offspring.

She stuffed it into the chamber, and once she had left I took a photo through the tiny opening:

It looks rather ferocious…

The food supply was evidently complete, because less than two hours later she had sealed it all up, and started to construct another cell.

This time I got photos of the process. She carried in her lumps of mud:

and used wet liquid mud laid down in rows rather like making a coiled pot.

Once she had inspected it,

she then settled in bottom first, and stayed for some time, presumably laying an egg.

She emerged, one last check, then left for the day. Next morning, she returned, and sealed this one up too:

Then she started another:

In aggregate she built six or eight chambers, and then finally the process seemed to have come to an end. The entire condo was given an additional mud cladding. It is 1″ across at the top, and 1 3/4″ long.

And she left, job done.

I read that the adult wasps would not emerge till the spring, but I was keeping watch just in case, and blow me if one morning I glanced at these muddy storage units, and discovered that two of the cells had escape hatches:

By my estimate, this was about a month from when the eggs were laid. One week later, there were four holes:

The next generation is launched.