You are here: Home » Blog » Archives for mason bee

Wednesday wordphile: ocellus (plural: ocelli)

An ocellus is a simple eye having a single lens. This type of eye does not form an image but acts as a photo receptor, detecting changes in light intensity and direction.

Many arthropods have ocelli. They are especially common in arthropods that fly—such as bees. Bees have three ocelli on the crown of their head–centered between the large compound eyes and looking like shiny black dots.

Experiments have shown that ocelli help honey bees to navigate at flight speeds. Bees with full sight (all five eyes) were found to be much more cautious and tended to decelerate more quickly than bees whose ocelli were covered[1].

The ocelli are the three tiny dots atop this mason bee's head. Photo by the author.
The ocelli are the three tiny dots atop this mason bee's head. Photo by the author.

[1] Kastberger, G. 1990. The ocelli control flight course in honeybees. Physiological Entomology 15(3):337-346.

Cat on a Mason Bee Condo

One morning this spring I went outside ready to take photos of mason bees coming and going from the bee condo. What I found there wasn’t a bee but my cat, perched about eight feet high on the roof of the bee condo.

Although my camera was basically prepared for some macro photography, I quickly took some shots of the cat. I failed to reset the metering mode and a few other things, so the pictures turned out terrible. Unusable . . . completely washed out. Every time I saw them I decided to delete, but I never quite got around to it.

Yesterday I was playing with PhotoShop, trying to learn how to use this mystifying piece of software. For some reason I chose the cat pictures as a learning tool. What I got was pretty cool–cat art!

So here, for your delectation, I present “Cat on a Mason Bee Condo.” Oh well . . . I don’t wander off topic too often.

Rusty

Cat on a Mason Bee Condo. Photo by the author.
Cat on a Mason Bee Condo. Photo by the author.

A chair with a buzz

The Adirondack chair, below, is in my yard. A close-up of one of the screw holes shows that a mason bee decided it was a good place to lay her eggs. A seal of mud now protects the eggs that are laid in individual compartments, end-to-end inside the hole. The fact that I provided perfectly good mason bee houses–carefully built to meet all specifications–was apparently lost on the female who chose this spot.

I probably wouldn’t have noticed this nest, except that I was sitting in that chair when it started to buzz. The chair, that is. I was really surprised when the little mason bee popped out of the side (under the arm) because she made a lot of noise. I decided to leave it alone–it’s a small nest and a big chair. There’s plenty of room for all of us.

Rusty?

Adirondack chair with a buzz.
Adirondack chair with a buzz.

?

Home sweet home.
Home sweet home.

Mason bees are not the answer

I see a lot of posts and tweets that seem to point to the mason bee as the answer to pollinator decline. Sure, I like mason bees, and here in the Pacific Northwest they have the added advantage of being native. However, we don’t yet have a consensus about what is killing the honey bee. If my hunch is correct—if the honey bee is declining due to contaminated pollen—then the mason bees (and other wild bees) are in danger as well.

Pollen is the primary protein source for these animals and it is critical for their health, growth, and development. In honey bees the pollen is first digested by the nurse bees and then fed as glandular secretions to the larvae. In mason bees, the pollen is left in the form of a provision which is eaten directly by the larvae as it grows. In either case, if that pollen is carrying pesticides, the larvae may die. Or—and this is harder to determine—the larvae may grow into adults that have abnormalities. These abnormalities may be morphological, behavioral, or reproductive. Any of these could cause the young bees to die or be unable to reproduce.

It is simplistic to think mason bees are the answer to the bee problem. By all means we should be encouraging mason bees—and all wild bees—by providing habitat, wildlife corridors, and continuous and varied forage. But we need to keep on top of legislators and demand testing of pesticide levels in pollen, testing of sublethal effects of pesticides, and pesticide regulation that is determined not only by toxicity to adult bees but to larval bees as well. The larvae are the ones most likely to be poisoned by pollen and we will have no bees—of any variety—if the larvae can’t survive.

We can’t expect the amount of pesticide in our environment to decrease until we demand organic food, demand that public lands not be sprayed, and until we stop using pesticides on our gardens, lawns, and homes. By pesticide I mean all the “cides“—insecticide, fungicide, acaricide, rodenticide, herbicide—it makes no difference. They all kill life, and many of them interact with each other, becoming even more toxic in the process.

Rusty