What mystery bee in my bee home?

A few years ago I made some mason bee homes. It didn't work out that well and I ended up storing the trays in my barn. Some where neatly stacked, some weren't. This fall I noticed that some of the holes were covered over. Someone had decided to call it home! I was curious what species it might be. Adding to the intrigue is that some of the nest holes that were used were only "half" a hole (I routered channels in my trays but they only form a full tube when stacked together, these trays against a flat surface).

Can anyone identify these cocoons?
I can't tell if it's either an immature mason bee, or a mature resin bee. The larvae itself looks like a resin bee but the cell dividers are mud instead of resin. I know a mature mason bee would be fully encased in a cocoon which is not the case here, maybe just too early in it's development?

In terms of climate; I'm in New Brunswick, Canada. Zone 4. Daily overnight frost now with first snow forecast for the weekend.

I'm really torn, because I've I heard the resin bee is invasive in which case I should consider destroying them. But if it's a mason bee I want to save them!

Hi Glenn;
I am far from a bee person, but those look like "mud dauber" nests. Wasps!
If so I recommend destroying them.

I agree with the Mud Dauber.

Thanks for the quick replies. I read up on mud daubers, seems they like to eat spiders. My barn is loaded with spiders so it seems even more likely that mud daubers would nest there.

Those don't really look like they were made by "mud dauber" wasps to me.

They do look like mason bees or possibly carpenter bees.

Mud daubers like to create their own mud tunnels for their offspring to grow up in and they put food critters in with their eggs.

Redhawk

Can you tell what kind of food was put in with the larvae?  Was it pollen (now mostly eaten) or spiders, or?

I looked again to check for evidence of food and found none. The cells are very clean, just filled with fat larvae. Whatever they had, they must have eaten.

If you're concerned at possibility killing the 'good bees' or keeping 'the bad bees', how about netting the motel so when they emerge you can easily assess them before release?

I assume, in that cold climate, the bees/wasps are now inactive till Spring, so it shouldn't stop new arrivals I.e. In our climate, they're coming and going like a Hilton Hotel, so it would be a bit disruptive.