The previous week had seen a couple of sunny days which brought out the bloom, but for the most part, the weather had been cold and damp all spring. Sun was predicted when we set out for Corbett, but on the morning of June 16 it was still overcast, with a temperature of 52oF at 10:24am.
When we got to the shelter next to the webcam (not yet functional), the first thing we did was remove the lids from the Osmia aglaia emergence containers and move them to the front of the shelter, in hopes that the bees would warm up quicker and fly. There were lots of emerged adult O. aglaia amidst the frass in the containers. It amazes me that they were still alive, since they probably had only one or two days of good weather since they had emerged about a month earlier. But the morning of the 16th they were not doing much. Here's what the shelter looked like after we arrived and opened the containers.
As the morning started to warm, O. aglaia began to appear from under the floor of the shelter where apparently quite a few bees, especially males like these, were hiding. Osmia lignaria (the big black bee sitting on the container lid) were more active than O. aglaia, but they also spent much of their time resting or waiting for the sun.
It's amazing to see these large female O. lignaria coming out of the small tunnels. Rosie had told us that the O. lignaria were using many of the smaller diameter tunnels, though larger tunnels are available. They seem to prefer the tunnels at the bottom of the Binderboard. The plugged tunnels are O. lignaria.
Our second stop was the shelter in the center of the fields, near the marion berries. The photo at the top of this post was taken from that shelter. It has only two O. aglaia emergence containers. Here we also opened the emergence containers to encourage the bees to fly. The O. lignaria were active.
A closeup of the O. aglaia Binderboard shows an O. aglaia abdomen in one of the nest tunnels. However, most of the plugs in these 1/4" tunnels are O. lignaria plugs of chunky mud.
The O. lignaria Binderboard in this shelter already has 43 plugged nests out of 98 available. Probably the unplugged tunnels have nests under construction.
Despite the cool, overcast conditions, there were lots of bees flying on the black raspberries, though they were not the Osmia. We saw plenty of honey bees and at least two species of bumble bees. There were bees flying fast above the berry bushes, too fast to identify. However, when I caught them with my net, they turned out to be bumblebees.
More about our visit to Corbett in the next post...