Well, we were probably a bit optimistic in putting the mason bees out on Easter weekend this year. Although the buds on the apple trees were swelling nicely at the time, the following 3 weeks of cold, dreary weather did little to advance the blossoms! Fortunately, the quince and dandelion kept our bees busy until the apple blossom appeared. Then we were able to see quite a variety of bees at work, during the few short, sunny hours that we've had. Our mason bees occupied 3 houses stationed around Cottage 20 and have so far filled 9 cells with eggs. That means a possible 'harvest' of over 50 mason bees to work for us next year!
We noticed that, just after their release, the mason bees were very active: watching one house for only 5 minutes, we could observe at least 3 trips into the house to lay eggs. The male bees were easily spotted sunning themselves on the porch, waiting for the ladies to bring home the pollen. On cold rainy days, the adults shelter in empty cells in the bee house, poking their heads out periodically to check the weather.
By the time the apples bloomed, activity was much slower and we think some of our bees may have left in search of earlier blooming orchards. Still, at least one or two females continued to lay and found the new houses we put up when the first one was nearly filled.
Lesson learned: wait. Wait more. They hatch pretty quickly if there is sun--ours were off to work within 3 days of being placed in a box tied to the bee house. Some hatch faster than others, so we're making new bee houses with permanent "emerging rooms": a part of the house in which the bees can be placed so that they remain dry and protected while they warm up and emerge from the cocoon. The emerging room has a small hole to allow the bees to get out when they're ready to go to work. We think this type of house will work better than tying a box of cocoons to the small bee houses we made last year--not so subject to wind, rain and predators.
We will move the bee houses to a sheltered location in about 2 weeks, after all activity has stopped, so as to prevent predators from disrupting the nests. We'll keep them warm and dry until the end of the summer, making sure they are not disturbed while the larval bees are developing. Then, in October at our Applefest, we'll open the houses and inspect the cocoons for signs of parasites, transfer them to cold storage containers and keep them cool until next spring. Over the winter, we'll clean the houses and re-line each cell with fresh parchment paper liners, ready for a new