Researchers at Dalhousie University are urging the public to be on the lookout for discarded paper wasp nests as the snow in Nova Scotia melts. The nests are being gathered from various locations in the province to investigate potential heavy metal contamination.
Carlie Ashton, an environmental science undergraduate at Dal’s agricultural campus in Bible Hill, is spearheading the research for her honours project. She is focusing on two species of wasps, aerial yellowjackets, and bald-faced hornets, known for constructing their nests using wood or plant fibers gathered from their surroundings.
The study aims to determine if urban wasp nests are more likely to contain copper and chromium, common wood preservatives, compared to nests in rural areas. Ashton explained that wasps in urban settings may be exposed to wood preservatives from sources like decks, while their rural counterparts primarily interact with natural materials such as trees.
Individuals who come across abandoned wasp nests are encouraged to contact Ashton to contribute to the study. The nests become vacant during this time of year as the cold weather leads to the death of the wasps, with the mated queens seeking shelter elsewhere.
Although the winter may have taken a toll on the nests, Ashton emphasized that the condition does not affect the research. She plans to dry the nests, dissolve the material, and analyze it for heavy metals using specialized equipment.
This study is unique as similar research has not been conducted on these specific wasp species in Canada, according to Ashton. The investigation will help determine if aerial yellowjackets and bald-faced hornets can serve as indicators of heavy metal presence.
Assistant professor Paul Manning, one of Ashton’s project supervisors, highlighted the importance of understanding the environmental pressures faced by insects. He noted that declining insect populations worldwide are attributed to various factors, including habitat loss, pesticide use, and climate change.
While the study does not focus on the impact of contamination on the wasps, Manning mentioned previous research suggesting that copper exposure could reduce lifespan and reproductive capacities in male wasps and affect the queen’s egg-laying abilities.
