By: Marcel E. Durieux
This article originally appeared in the Summer 2020 issue of BEEKeeping Your First Three Years
One of the happy differences between beekeeping and managing other livestock is that our bees live with us voluntarily. We don’t confine them. They can leave and abscond any time they wish to go (and on rare occasions, they do). We provide them with as good a living space as we can, we take care of them as good as we can, and most of the time they willingly stay and pay us back for our care in honey and wax. To me, this makes the experience quite different from, say, keeping rabbits or goats.
The author watches the arrival of a swarm at a bait box on his porch. Photograph by Marijke Durieux, with permission.
In the same manner, by providing as good a space as possible, we can induce a swarm of bees to come to a place we offer them, rather than have their scout bees select one of the multitude of other nesting sites available. It is hard to imagine now that before 1975 this had never been done, or at least never been described, but thanks to the work of Seeley and co-workers, we have a very good idea of what scout bees are looking for in a future nesting site (Seeley, 2010). If we provide them with a space that fits their needs, they’ll come. This activity doesn’t yet have a name that truly expresses the completely voluntary nature of the bees selecting your space: “swarm trapping” or “swarm baiting” doesn’t quite do it justice.
Admittedly, there are some downsides. You don’t know where the swarm came from and what diseases it might possibly carry. Bees like their nesting sites inconveniently high up in trees, which makes retrieving the box with the swarm a bit of an adventure. And, if we base our stock on swarms, it is at least conceivable that we might be selecting for bees that are likely to swarm again in the future. But by and large attracting swarms is a great way to save hundreds of dollars in obtaining bees. In this article, I want tp make the point that there’s more to it than that: offering new homes to bee swarms is of critical importance to the bees themselves, particularly in the urban environment.
We all know now that urban beekeeping is not only feasible and enjoyable, but that it also is a great way to bring nature into the city and to help pollinate the urban setting. In fact, there’s a regular feature about it in this Journal. But bees in the city not only bring us pleasure and benefit: city life makes bees thrive as well. Bees do wonderfully well in the urban environment. A good test for this is the ability of new colonies to live through their first Winter. This is not an easy thing, and feral colonies in the wild are more likely than not to succumb during the cold season: only about 25% of swarms survive (Seeley, 2010). Of colonies managed by humans, about 40% survive. But these are data from the more typical rural settings where bees are kept. Of colonies managed in urban areas, more than 60% make it through their first Winter (Wilson-Rich, 2012)! In other words, young colonies do better in the city than they do in the countryside. We see a similar trend if we look at production: first year honey yield in rural areas in one study was 17 lbs, whereas in urban areas it was 26 lbs – close to twice as much (Wilson-Rich, 2012).
Why is it that new colonies do better in the urban setting? It is not because there are fewer pesticides in the urban environment. It is not because they are exposed to fewer diseases. Both these issues have been investigated: the urban environment actually carries a higher pesticide load (all those people spraying their small backyards?) and there are more bee diseases around. The difference appears to be in the availability of a diverse habitat and a large variety of plants to forage on. Recent studies have shown great differences in the number of plant species foraged on by bees (and therefore present in honey) from different locations. In rural areas, typically 150 species are found in honey. Moving to the suburbs, the number drops to about 100. But in the urban environment, more than 200 are present (Wilson-Rich, 2018)! So city bees choose from a wider range of flowers. Other explanations for bees doing so well in the urban setting have been suggested, but have not been investigated: for example, cities are somewhat warmer than the countryside, which might help during that first Winter.
Now, let’s get back to attracting urban swarms. As we saw, a feral bee swarm has only a one-in-four chance to survive. For a feral swarm in the city survival will probably be even less likely, as many swarms will find housing where they get in the way of humans, and may be destroyed. In contrast, we also saw that if you provide that swarm with a city home, their survival rate will more than double! In addition, they will thrive, bringing in more honey from more plant species than would be the case in areas outside the city. Thus, providing housing for swarms in the urban setting is of great benefit to the bee population there.
Importantly, that urban bee population might be the future of the species. There are those who feel that the “urban islands” in the sea of agriculture are in fact where bees will be able to thrive again. Open grassland has been and is being eliminated at a high rate to support intensive farming. Urban areas may become the new countryside for bees (Benjamin, 2014). Supporting the bee population in urban settings may therefore be of critical importance.
This is not the place to discuss the technicalities of attracting swarms. Seeley and Morse’s classic pamphlet on “Bait Hives for Honey Bees” is freely available on the web and explains it all (Seeley and Morse, 1989). It’s fairly straightforward: all it takes is a box of the right size, some comb, some lure, and some knowledge of bee preferences. The biggest hassle in putting up bait hives – getting them high enough – is less problematic in the cityscape. As mentioned, bees like their nests high (15′) in trees, presumably because they are more safe there from large predators. Unfortunately, getting a box up a tree that high is impractical, it can’t be checked easily, and everything becomes even more exciting when it needs to be lowered again, full of bees! In the city, this is all easier, since typically it will be very feasible to find a ledge, balcony or roof at about the right height, and where access is straightforward (see Figure).
In summary, for the urban beekeeper, attracting swarms is so much more than getting free bees. It is even more than a way to get more bees into the city, improve pollination and get a new generation of city dwellers to become familiar with these amazing creatures. It is, truly, a way to sustain our bee population at a critical juncture in their millions of years of history.
