A researcher is investigating the impact of an invasive insect and the chemicals utilized to combat it on the species residing in ancient hemlock forests. The hemlock woolly adelgid (HWA) has been causing significant damage to forests in the southwestern region of Nova Scotia for nearly ten years. To address its spread, various entities including Parks Canada, the province, local groups, and private landowners have been employing insecticides such as imidacloprid and dinotefuran. However, Mathilde Christjansen, a master’s student at Mount Allison University in Sackville, N.B., highlighted the lack of knowledge regarding the effects of woolly adelgid and the insecticides on other species.
Christjansen emphasized that while imidacloprid is designed to impact insect nervous systems, it can also affect the nervous systems of other animals. The researcher proposed using the eastern red-backed salamander as a bioindicator species to provide insights into the overall forest ecosystem health. By focusing on this amphibian, the team aims to gain a comprehensive understanding without studying every species in all hemlock forests individually.
Last year, scientists placed coverboards in forests to serve as shelters for salamanders. Through periodic surveys, the team counted and monitored salamanders living beneath the coverboards, conducting tests to assess their behavior. The study includes forests treated with either or both insecticides to combat HWA, as well as untreated areas.
In collaboration with various institutions, including Mount Allison University, Canadian Forest Service, Acadia University, Environment and Climate Change Canada, and the University of Saskatchewan, the project aims to evaluate forest health in Eastern Canada. The research focuses on the impact of dying hemlocks on salamanders, as these trees create unique habitats essential for the species. Salamanders, with their high abundance and sensitivity to environmental changes, serve as valuable indicators of forest well-being.
The study will continue until the next year, with data collected during the summer being analyzed for further insights. The project’s findings are crucial for understanding the broader implications of insecticides and invasive bugs on forest ecosystems and wildlife.