Scientists from the University of Guelph have discovered that two urban bee species in Toronto, Canada are making nests out of plastic bags and plastic building materials.
Scott MacIvor, lead author of the study, says the discovery is important because it shows bees’ resourcefulness and flexibility in adapting to a human-dominated world.
“Plastic waste pervades the global landscape,” said MacIvor. Although researchers have shown adverse impacts of the material on species and the ecosystem, few scientists have observed insects adapting to a plastic-rich environment, he said.
“We found two solitary bee species using plastic in place of natural nest-building materials, which suggests innovative use of common urban materials.”
One species was occasionally replacing plant resins with polyurethane-based exterior building sealants, such as caulking, in its broad cells. Broad cells are crated in a nest to rear larvae. A second species was using pieces of polyethylene-based plastic bags to construct its brood cells. The glossy plastic replaced almost one-quarter of the cut leaves normally used to build each cell.
Markings showed that the bees chewed the plastic differently than they did leaves, suggesting that the insects had not incidentally collected plastic. Nor were leaves hard to find for the bees in the study.
“The plastic materials had been gathered by the bees, and then worked – chewed up and spit out like gum – to form something new that they could use,” said Andrew Moore of the University of Guelph.
In both cases, larvae successfully developed from the plastic-lined nests. In fact, the bees emerged parasite-free, suggesting plastic nests may physically impede parasites, the study said.