Bee hotels are a type of insect hotel for solitary pollinator bees, or wasps, providing them rest and shelter.[1] Typically, these bees would nest in hollow plant stems, holes in dead wood, or other natural cavities; a bee hotel attempts to mimic this structure by using a bunch of hollow reeds or holes drilled in wood, among other methods. Bee hotels can possibly support native bee and wasp populations by adding nesting resources to a habitat. However, some activists have criticized bee hotels for being ineffective at rehabilitating native bee populations and possibly harming them by providing homes to invasive species and creating grounds where bees can transmit diseases to one another.[2]
A beehive is where bee colonies or communities live and raise; a bee hotel's purpose is to solely attract bees that do not make their homes in colonies, but instead build individual nesting sites of their own, referred to as "solitary bees."[3]
Bee hotels are constructed in a manner to mimic the real life structures that solitary bees nest in. They incorporate reeds, bamboo or other materials to create a bundle of horizontal tubes, open at one end, closed at the other.[4] These horizontal tubes range 12-20 cm in length, and 2-12 mm in diameter. These nested tubes require maintenance and cleanliness as bees in hotel are more susceptible to disease, such as the spread of chalkbrood.
However, bee hotels could also provide homes to invasive species and species of wasps that predate on bees, making predation from parasitic wasps and kleptoparasites more likely than in naturally built nests.[5]
Dead, walled-up cells from previous years should be removed. Bee cells taken over by the parasitic Cacoxenus indagator fly should also be removed to prevent spreading.[6] Be careful when selecting the wood to construct your bee hotel, as certain woods may not provide sufficient weather protection, especially in wet weather. Certain woods are also more prone to splintering inside the tunnel.
Approximately 30% of the 5,000 native bee species in North America build nests in tunnels or cavities situated above ground.[7]
The 2021 scientific publication Worldwide occurrence records suggest a global decline in bee species richness indicates a downwards trend in the global bee population.[8] In order to try and reverse the perceived reduction in bee numbers, some people construct bee hotels.[9]
A study of 200 bee hotels undertaken by melittologist Laurence Packer and Scott MacIvor from York University indicated that 50% of bee hotels in their study were dominated by wasps. Bees, unlike wasps, favour hotels that receive direct (especially morning) sunlight, and that are closer to the ground. Bee hotels located on multi-storey building rooftops and in shaded areas are more likely to attract wasps. The study critiqued poorly designed and maintained bee hotels, noting that plastic tubes can be a catalyst for mould, narrower tubes can discourage female bees, and proximity of spiders can reduce bee populations. Peter Hallett, a melittologist from the University of Toronto noted that the wasps observed in the study were not yellowjackets, but solitary wasps that are generally perceived more positively in North America.[10]
Melittologist Cory Sheffield of the Royal Saskatchewan Museum observed more positive trends in bee hotels used by bees in orchards in Nova Scotia and noted that some of the problems from the Toronto study were unique to cities. Both Cory Sheffield and Laurence Packer encouraged creation of bee hotels, despite the issues identified in the Toronto study. A Canadian study of 200 bee hotels in Toronto indicated that 50% of hotels were dominated by wasps, 25% by invasive, and 25% by natives.