Incubate emerging berry bees

Back in April Dr. Jim Cane sent me this image of a incubator for O. aglaia. "Basically a box with a seedling grow mat on the floor and a thermometer. Big box in this case because we are loosely stacking in our foam nesting blocks with nests. No risk of overheating because the low wattage grow mats can’t heat to more than about 80F. I do not yet have a consistent response to duration of incubation…some years just a few days, others nearly a week."

"...one simple yet handy observation you can make are the weather conditions under which you do or do not see foraging activity at nesting blocks (Osmia aglaia) or at flowers (groups you can recognize, like honey bees, bumblebees, etc.). Shade temperature, sunny or not, calm or not, active or not, hour of day.

"My impression with O. aglaia is that 60F, calm and sunny is about their minimum threshold for flight. In contrast, here the other day I had blue orchard bees flying at my nest blocks at 45F (!), again sunny and calm in between snow squalls."

We should try to get more of this data next year. Hopefully once we have a webcam running, with a thermometer in the bee shelter, we'll be able to gather this information remotely.

I wonder if our solar panel will generate enough power to run a grow mat as well as the webcam? Otherwise a grow mat is not a viable option for us.

Checking Bee Activity

Our project was on hold for the month of May while I spent time helping my mother recover from eye surgery. What was supposed to be a 5 day trip turned into a month long visit. The Oregon Berry Bee Project is getting back on track now.

On Thursday, June 4, Steve and Mike visited the Sturm farm to see how the bees were doing. Steve noted that lots of adult bees were sitting in the emergence boxes waiting to emerge. The boxes were in the back of the shelter. He thought perhaps they didn’t have enough light to see the emergence hole. When he opened the box, many bees emerged. Soon there was lots of bee activity at the Binderboard® nests. That afternoon he saw bees plugging the first complete nests, so presumably some bees had already emerged.

Jim Cane warned me that the bees might need incubation to emerge in time for raspberry bloom. Perhaps warmth, not light was what the adults in the emergence box needed. Perhaps both warmth and light.

Steve also noticed that quite a few O. aglaia were on the ground sunning. Mike took some great photos, below and top of this post. When I first saw O. aglaia nesting in alfalfa leafcutting bee blocks in Medford, OR, I recall many bees sunning on the ground as well. We’ll have to spend some time next year trying to understand when and why they do this. (All of these photos are female O. aglaia)

Note: These females are about 1/4 inch long. There are also metalic blue individuals.

By late afternoon Steve estimated that about 90% of the bees in loose cocoons from last year had emerged.

On June 4 the Raspberry vines had lots of developing berries and only a few flowers left. Steve estimates that raspberry vines were 90% fruit and10% blooms. The emerging O. aglaia probably had a distance to fly to blackberry and marrionberry vines which were in full bloom. We’ll have to keep that in mind and be sure to come in May next year to observe raspberry pollination.

Steve set up another shelter for O. aglaia closer to both the marionberry and blackberry vines, located approximately 400 yards from the original site. Rosie had two more leafcutter Binderboard to put in the shelter, and Steve used one. Steve put the straws with O. aglaia into that shelter, since many of the bees in straws apparently had not yet emerged. Steve placed the straws in a watertight container which he then attached to the shelter to keep it out of the rain. As it turned out, a terrible weather cell hit the farm and surrounding areas that very same afternoon and evening!

I’m getting the impression that O. aglaia emergence is better timed with blackberry than with raspberry. We will have to warm them more than we thought to get them out for raspberry bloom. On the other hand, we could use O. lignaria for raspberry pollination; their emergence could easily be delayed.

Steve and Rosie toured the fields, observing the “catch” Binderboards on the perimeter, and found that there was a small amount of activity, and a sealed chamber at two of the six sites visited. The Himalayan blackberries were in full bloom, like the cultivated blackberries.

Don commented that this is the best pollination that he has seen on his three acres of black raspberries. They are now four years old.

Meanwhile Mike, our webcam expert, has prepared a list of equipment that the Sturms will order as soon as the grant money comes through. More about that next.