Native Bee Condo
In an effort to support native pollinators, many people are planting pollinator-friendly habitat and constructing various types of bee houses or the larger bee “condos.” However there is some controversy around the issues of concentrated populations of bees (or anything else) due to high levels of disease and infestation that can develop (similar to the issues of CAFOs for cattle). There is a fairly do-able process to properly maintain the smaller bee boxes, but due to the size/scale of the bee condos, it’s a more challenging issue with the larger bee condos.
Dale has designed a native bee condo that addresses these hygiene issues. We sent the plans to the Xerces Society to review and provide feedback; they gave it a solid thumbs up and asked that we stay in touch with them about the project and let them know how it goes. Meanwhile, the Kalamazoo Land Bank asked us to coordinate a grant funded community project to construct the bee condo at Riverview Launch (1523 Riverview Drive, Kalamazoo). So Dale passed the plans on to Tomme who engineered, constructed the bee condo. We installed it at Riverview Launch and held a community workshop where people learned about the importance of native bees while stuffing the nesting materials and planting a pollinator garden around the Bee Condo. So if you’re driving along Riverview Drive, or peddling along the KRVT alongside Riverview Launch, take a few minutes to stop and check it out. And who knows, one may pop up in the Trybal Revival Eco-garden one day as well!
Many of our native bees are in the Mason Bee family and form their nests in tubes. In nature this would be hollow reeds, woodpecker or beetle holes in trees, or any other tubular hollow space. The issue with bee houses (also called bee boxes) is due to dense populations of bees in close proximity; the nesting materials become infested with parasites and breed disease. The bees don’t know this however and they are drawn to nest in these perfect tubes. After several years of use, these well-intended bee houses are actually doing more harm then good because the bees will not only die, but further spread disease to other healthy bees.
The challenge lies in the fact that the nesting materials are used by the bees in one stage or another all year round. They emerge in the spring as new adult bees, and immediately form their own nests to lay their eggs in. The eggs develop into larvae over the summer and fall and they remain in the nesting tubes dormant over the winter, waiting to start the cycle all over again in the spring. So it’s not like you can wait for the nest to be empty and just toss the old nesting tubes and start over—if you toss the nesting tubes you are tossing the bees with it.
There is a process for dealing with this on a small scale (the bee boxes). While the larvae is dormant you carefully remove the nesting tubes and put them in a light-tight container with a 3/8″ hole drilled in the bottom and store it in a cold place for the winter, such as a shed. (Something like a opaque 5 gallon bucket with a tight lid works well.) Meanwhile insert new nesting tubes in the bee box. In the spring, bring the container out and place it near the bee box. The bees will emerge from the old nesting tubes in container and be drawn to the light, exit the hole and find the new nesting materials in the bee box nearby. It is recommend that the nesting materials be replaced every 2 years.
Obviously this is not possible with the large bee condos. This was the problem we needed to design for. Our solution is described below—this will make much more sense if you download the pdf and look at the plan.
- Within a permanent and well-anchored structure, the nesting materials will be placed in a large double-sided cube-like compartment. A removable light-tight cover with a few small holes drilled in the bottom will initially cover “side B”. When the bee condo is first erected, it will be placed with “side A” (uncovered) facing south-east — this will be the active (front) side for 2 years.
- After two years, during the dormant season, the cube will be rotated, the cover will be removed from side B and placed over side A. Now side B is facing south-east and is uncovered, and side A is covered and facing north-west. In the spring, the bees in side A will emerge and exit through the holes in the cover and go find the new nesting materials in side B.
- This rotation process will be repeated every two years at which point the nesting materials will be replaced on the new “front” side for the bees to find the following spring.