A Mason Haven! :)

 Look at how many of the new tubes are filled already! :)

 See that thick layer of yellow pollen sticking to the fine body hairs? :)

 With that capacity to carry so much pollen, it's not surprising that the tubes ...

 are being filled so quickly! :)

 You'll notice this Mamma bee is backing into the tube to lay a potential baby! :)

 Once the baby is safely within, a layer of pollen will be added! :)

 Followed by another baby, ...

 and more pollen! :)

 Each tube will have around 5 babies within, once filled! :)

 It's said that the Mammas put the female babies in first, with the males added at the front end of the tube! :) Come Spring the males will emerge first, and when the females emerge they will mate and tube filling will begin by the females! :)

 As I watched them working, I noticed the females were carrying so much pollen that ...

 some of the pollen was falling from them in air, like an airline streamer! :)

 You can see it on the tubes and on the floor of the house! :)

 There's something joyful about watching them work! :)

 They have a mission in their short life and they are about fulfilling it! :)

 This is my favorite Mason Bee photo so far! :)

 This photo is out of focus but I added it anyway because that pollen load is impressive! :)

 Each Mason Bee does a great job of remembering which tube she is working to fill! :)

 I could watch them for hours! :)

 This year I added 6 new houses to complete the row! :)

 They are filling them so quickly that I bought 9 more houses, ... enough for a full 2nd row! I will wait to add them until all the empty tubes are filled! I hope to be able to add the 2nd row next year! :)

So far they show no sign of running out of pollen, and I've been buying more flowering perennials to make sure they don't! I'm doing my best to see that they have enough real estate! :)
It's turning into a Mason Haven! :)