How-to: First steps in Fall cleaning of mason bee cocoons after harvest
It is time to clean out nests and harvest your cocoons:)
I have mason bees at a number of sites, and decided that today was a good day to harvest cocoons from one of these sites.
The first step in cleaning cocoons is harvesting them out of nesting tunnels. The easiest way to do this is with a scoop. Once harvested, cocoons and other debris are added to a bucket of tap water. The reason for placing cocoons into water is to dislodge and loosen mud plugs from cocoons, remove some of the mites and separate other debris from healthy cocoons. The overall objective is to clean cocoons of any debris (mud and feces) and pests (mites) and to clean cocoons well enough so these can be candled. Candling allows you to remove any parasitic wasps.
I scooped out cocoons , placed them in water -and saw a photo op! A lot can be learned from examining cocoons and other debris.
The upper picture is a surface view of cocoons floating on water. Mason bee feces (yellow), mites, cocoons and bee pupae can all be seen in this picture. I cropped small areas of the same picture to make it easier to point to these features.
An additional photo was taken of a pollen lump after it was removed from the water. Pollen lumps are pollen collected to feed individual bee offspring. If this tiny bee larvae dies, it leaves the remains of the pollen lump. In cold damp springs, more pollen lumps can be seen because during cold weather, young bee larvae are more likely to die