The Killing Fields
by Katie Rook
photography by chris robinson
With the warm weather upon us, Canadian farmlands are thick into the growing season. But not everything in nature is benefiting.
According to York University biologist Bridget Stutchbury, two regularly used agricultural insecticides are killing and disorienting white-crowned sparrows flying over or nearby farmers’ fields.
“Birds use a suite of tools to chart their path. They have innate star maps in their heads which they use in addition to major landmarks and polarized light,” says Stutchbury, a celebrated avian specialist who collaborated with researchers from the University of Saskatchewan in studying the detrimental effects of insect-killing neonicotinoids on migratory songbirds.
“If a chemical throws off their migration, it could cause a delay in breeding and even death.”
Specifically, the chemicals looked at were imidacloprid and chlorpyrifos, insecticides so common they are found in most grocery store produce.
Published in Scientific Reports, 57 last fall, the study focused on Gambel’s white-crowned sparrows, which had stopped to refuel in Canada’s Prairie region en route from the southern Gulf states.
Birds captured for research purposes were whisked away to the aviary at the University of Saskatchewan’s Facility for Applied Avian Research where they were fed pinch-sized doses of insecticide-coated sunflower seeds.
As observed, some of the birds became hopelessly lost, attempting to fly east rather than north toward the Arctic tundra, and some rapidly lost weight. Others weakened and died.
While the study did not reflect on how insecticides might affect humans, Stutchbury is raising alarm about the impact of even small doses of chemicals on birds’ powerful navigation abilities.
Next steps include examining the chemical impact on other seed-eating birds, a research project supported with additional funding received from the Kenneth M. Molson Foundation in January.
“Birds are sensitive indicators of our environment,” Stutchbury says. “If they’re not surviving in the wild, then something is very wrong.”