As the winter snow in Nova Scotia starts to melt away, researchers at Dalhousie University are urging the public to be on the lookout for abandoned paper wasp nests. They are specifically interested in collecting these nests from various locations across the province to examine them for signs of heavy metal contamination.
One of the researchers involved in this study is Carlie Ashton, an environmental science undergraduate student at Dalhousie University’s agricultural campus in Bible Hill, N.S. This research forms part of her honours project. Ashton is focusing on two species of wasps, aerial yellowjackets, and bald-faced hornets, which construct their nests using wood or plant fibers collected from their surroundings. These insects chew the materials to create a pulp that is then regurgitated to form the nest structure.
The study anticipates that wasp nests in urban areas might exhibit higher levels of copper and chromium contamination, commonly found in wood preservatives, compared to nests in rural settings. Ashton explains that wasps in urban regions may gather materials like deck wood, which likely contain wood preservatives, leading to heavy metal exposure, unlike wasps in rural areas that primarily utilize natural sources such as trees.
If you come across an abandoned wasp nest, Ashton encourages you to contact her to contribute to the research. Typically, these nests are deserted during this time of year as the cold temperatures cause the wasps to perish, while the mated queens seek shelter elsewhere, such as under tree bark or in logs, woodpiles, or leaf litter.
Although the condition of the nests post-winter may not be pristine, Ashton mentions that it does not affect her research. She plans to dry the nests in a microwave, dissolve the material, and analyze it for heavy metal content using specialized equipment.
According to Ashton, while similar research has been conducted on other species elsewhere, studies on these specific wasp species in Canada are scarce. The project aims to determine if aerial yellowjackets and bald-faced hornets can serve as indicators of heavy metal concentrations, which could provide insights into the environmental pressures these insects face.
Assistant professor Paul Manning, one of Ashton’s project supervisors, highlights the importance of understanding the presence and levels of contaminants to comprehend the challenges insects like wasps encounter. He emphasizes the various stressors, such as habitat loss, pesticides, and climate change, contributing to the global decline in insect populations.
Although the research does not focus on the impacts of contamination on the wasps, previous studies suggest that copper exposure can reduce lifespan and reproductive abilities in males, as well as affect the queen’s egg-laying capacity.
By contributing to this study, individuals can help shed light on the environmental challenges faced by these insects and contribute to broader conservation efforts.