As the winter snow in Nova Scotia begins to melt away, researchers at Dalhousie University are seeking abandoned paper wasp nests for a study on heavy metal contamination. Carlie Ashton, an environmental science undergraduate student at Dal’s agricultural campus in Bible Hill, is leading the research as part of her honours project. She is focusing on two species, aerial yellowjackets and bald-faced hornets, known for building nests using wood or plant fibers collected from their surroundings.
The study aims to compare the levels of copper and chromium contamination in wasp nests between urban and rural areas. Ashton anticipates that nests in urban settings, where wasps may gather materials from treated wood like decks, could show higher heavy metal contamination compared to nests in rural locations where natural sources are more common, such as trees.
Individuals who come across abandoned wasp nests are encouraged to contribute to the study by contacting Ashton. These nests are typically deserted during this season as the cold temperatures lead to the death of the wasps, with mated queens seeking refuge in places like under tree bark or within logs and woodpiles. The collection of specimens is expected to be completed by May before the wasps start building new nests.
Despite the wear and tear on the nests after winter, Ashton will analyze them for heavy metals by drying the material in a microwave and using a specialized machine for testing. This research, focusing on aerial yellowjackets and bald-faced hornets, is unique in Canada and aims to determine if these species can serve as indicators of heavy metal presence.
Assistant professor Paul Manning, a supervisor on the project, highlighted the importance of understanding the environmental pressures on insects due to various factors like habitat loss and pesticides. While the study does not delve into the effects of contamination on the wasps, previous research suggests that copper exposure could affect their lifespan and reproductive abilities.
The ongoing research seeks to contribute valuable insights into the challenges faced by insect populations worldwide.