
March 23, 2013…mounted on solar wall awaiting the hatching. Home made wooden nesting boxes on bottom, purchased plastic box on top.

Mid June…18 Tubes are filled. It looks like some predation is taking place, I should move them carefully to the house, standing them in the same orientation so they can finish their metamorphisis.
Mason bees are solitary bees but they also prefer to live close to each other. The females each nest in their own tubes and do not help each other. They only raise one generation a year.
The life cycle of a Mason bee according to Our Native Bees, A day or two after mating the females begin searching for new nest sites, such as insect holes bored in wood, plant canes, gaps in siding, masonry weep holes and, of course, Plan Bee Houses, if they’re lucky enough to find one!
Each female constructs her own brood cells using mud (Orchard Mason Bees) or leaf pieces (Leafcutter Bees) to partition each brood cell. She forages for pollen and nectar, and makes a pollen-nectar loaf upon which she deposits one egg. She then seals the cell with either mud or leaf pieces, and begins the process again, normally making 6 – 7 brood cells in a 6″ deep hole or nesting straw. About one week later the eggs hatch and the larvae feed until they’ve eaten all their food supply, which takes approximately six weeks. By late June the larvae spin cocoons around themselves and have developed into pupae, or fully-formed adult bees, by late summer. From September to April they remain dormant in a state of ‘diapause’ until the warm spring temps awaken them and the amazing cycle repeats itself.
By comparison, honeybee worker development is 21 days, egg to adult.
Fun facts from Kym Pokorny of The Oregonian…
Females decide whether to lay a female or male egg. A female lays about three to four male eggs for every two females because males emerge from the nest first and are more likely to end up as dinner for a predator. Since the males have no other job except to fertilize the females, they stick around the entry waiting for a female to emerge.
It takes the female about 15 to 35 trips — with 75 flower visits per trip — to collect enough pollen and nectar to feed one larva. She lays approximately 30 eggs in her lifetime.
Keeping mason bees is one of the easiest method of beekeeping. What is so amazing about them? 200 mason bees will out-pollinate 2000 honey bees, they will fly at cooler temperatures than honeybees, and rain doesn’t bother them. Mason bees rarely sting.
How do Mason bees pollinate so well? Their pollen is gathered ‘dry’ on the underside of their abdomen. It’s more easily transferred than the wet pollen of the honeybee.
It’s November now. The adult bee is fully formed and it’s the time of year to inspect for Chaetodactylus mites, (not Varroa mites, common on honeybees). Some people advise to wash the cocoons in a sieve with warm water. I hesitate to do that, it seems like it might be too rough. I opt to unroll the tube and gently brush off the debris.

108 adults this year. They look good as compared to last year when we didn’t inspect until just prior to putting out the cocoons in late March. We have found in this moist area, the bees seem to prefer the wood nesting blocks as opposed to plastic homes. They nested in 21 holes and only one in the plastic box. Last year when I only used the plastic box there was mold in the tubes. I’m not sure if it was due to the plastic or the length of time that I waited.
The start of the Mason bees this year.
Launching Mason bees in 2014 (from these cocoons)
Amazing stuff Pat, very educational 🙂 We have lots of bees that nest in the old stable walls, along with bumble bees; I wonder if they are a type of mason bee? I’ll take more notice next year.
Our Mason bees are usually mudded up by mid June. But there are the leaf cutter bees and other solitary bees that might be nesting later in the summer. Oh yes, the bumblebees seem to like to nest inside walls too. Me thinks you’re going to be verrrry occupied when you get back to Poland. You won’t be taken too much notice of bees…maybe of a certain baby, tho. 🙂
Fascinating. Will you be putting the cocoons back in the tubes for the rest of winter?
I’ll probably use the ‘launch box’ again or something similar to it. You can see the small cardboard box with a small hole in it above the homemade wooden nesting boxes and to the right of the plastic ‘house.’ I wouldn’t trust myself in trying to get the cocoons back in the tubes. I might get them in backwards or in the wrong order. We wouldn’t want the male bees hatching but not being able to get out of the tube because the unhatched females were blocking them in. Until mid March, I’ll keep the cocoons in the frig so they won”t hatch too early. We want to ensure there are plenty of flowers to pollinate. Maybe my newly planted bulbs will be among the first they will visit. 🙂