There was also some dead mason bees that failed to spin their cocoons.
But I ended up getting 102 cocoons this first season. We will see how many survive come this spring.
I have a cooler which I keep in the garage with the bee's placed in a dry soft cardboard box. The temperature seems to be pretty constant somewhere in the low 40's. However I may transfer them to the fridge later this winter. The bees will begin to "hatch" once they sense three days or so in the low to mid 50's. In Western Washington this can occur when there is plenty of winter left. So regulating their environment is wise if you don't want them to release prematurely. The bees are in a state of semi-hibernation so they are expending a little energy. Too much time in a fridge or cooler and they will die.
Once spring begins I will probably release about 20 at a time in week long intervals.
A dirty tray needing to be cleaned, an old toothbrush should suffice maybe with a very weak bleach solution.
102 bee cocoons. Most of these came from wild bees that were attracted naturally. Can't wait to see how many make it.
Something to keep the cocoons in. Keep them cool 35°-45°, and with a relative humidity around 60%, which is more moist than most refrigerators.