Carpenter Bees Buzzing Pollen

I’ve been keeping watch on the Evening Primrose to find out what insect is responsible for pollination and have finally found a likely candidate.  There have been no late night moth visitors, but I’ve seen a lot of early morning Carpenter Bee activity.

Pollen grains on the body and legs of the bee suggest effective transport of pollen between flowers.  This is what you would expect from a bee.  The unusual aspect is the method in which the Carpenter Bee collects that pollen.

The bee lands on the flower, but it doesn’t stay there.  Immediately after setting down, the bee crawls on over the flower and begins moving down the stem.  The trip across the flower is the maneuver that deposits pollen.

At a point on the stem just below the flower, the bee gets itself carefully positioned.

Then it hugs tightly to the stem and vibrates, an action known as buzz pollination.  The pulsations from the vibrating bee cause the pollen grains to fall from the flower’s anthers.

In some types of flowers the pollen falls onto the bee.  I’m not sure the shape of the primrose bloom allows much of the pollen to fall free of the flower, so buzz pollination wouldn’t appear to be the best strategy for this species.  The fact that the method is working for both bee and flower suggests that I don’t know everything there is to know about pollination methods.  Animals do what they do because it works.  I shouldn’t be second guessing their actions.  

Woodpecker Knocking

I was working in the basement the other morning when I thought I heard a knock at the door.  I stopped what I was doing and went upstairs to see who it was.  There was no one.  I went back to the basement and soon heard the knock again.  No one around, but I did hear the knock just before opening the door and I had a pretty good idea of what it was.  I waited upstairs until the knock came again and caught this Downy Woodpecker tapping away at the fascia board around my porch.

He took off when he noticed me looking out the window.

The woodpecker was busy exposing Carpenter Bee tunnels running inside the board.  This section of tunnel was opened several weeks ago, but I never caught sight of the bird.  The tunnels were cleared of everything edible, so I wasn’t expecting the woodpecker to return.

This time a different tunnel was under attack.  The larder looks full.  There are definitely some shiny insect parts showing through the holes.

I used some forceps to draw the bee closer to the opening.  Carpenter Bees spend the winter inside unused tunnels.  I imagine this guy will be woodpecker food before too long.

Ants and Carpenter Bees

I came home from work the other evening to find a pile of debris on the front porch. Debris on the porch isn’t unusual, but I’m usually the party responsible for putting it there. This wasn’t done by my hand and to make it even more intriguing, it seemed to be moving.

The apparent movement was supplied by a mass of ants. These were one of those species of tiny black ants that are about impossible to see without magnification. What ever the stuff was, ants found it attractive.

The ants were busily breaking the large lumps into small bits.

Their food caravan went off across the porch and disappeared into a crack. I knew the colony was there. Occasionally, small conical piles of dust appear along the crack as the ants enlarge their living quarters concealed beneath the concrete slab.

As I watched the ants work, a few tiny crumbs fell from above and added to the pile. Looking up, I found that Carpenter Bees were excavating brood tunnels in the siding around the porch ceiling.

Fresh material was being pushed from the hole directly above the debris on the porch. It looked to me like it was just typical wood shavings coming out of the hole. Where was the stuff the ants were eating?

The answer came when the bee pushed the material free. The wood shavings were caught by a breeze and blown away from the porch. Heavy material, mixed in the wood shavings, fell straight down and accumulated beneath the hole. The material being eaten by the ants must be material that was collected to feed the bee larvae. Why was the bee throwing it out?

I think the whole story came together when a second Carpenter Bee showed up and tried to enter the already occupied hole. There are two holes fairly close together. I believe the left hole was begun first, followed a short time later by the right hole. The bee in the left hole finished excavating its tunnel and began to collect food material for the brood chambers. The bee in the right tunnel was still in the process of excavating, when it somehow got into the wrong hole. It continued to excavate, but the material it was taking out was the food material the other bee had put in. I folded a small grass leaf and put it in the right hole to see the hole was still being used. If a bee was using the hole, it would move the grass. The grass is still in place, so it appears that the right hole has been abandoned. It's always fun when something new and interesting is waiting for me the moment I arrive home.