2026/03/17 by Alina Rutherford, Nelson J. O’Driscoll, Dave Shutler · 1 voice
Environmental Science · #Mercury impact and mitigation studies #Turtle Biology and Conservation #Marine animal studies overview
paper · doi:10.1080/15594491.2026.2630122
Methyl mercury is a neurotoxin associated with changes in reproductive behavior and success, hormone production, and survival in a variety of organisms. Pelagic seabirds often have high total mercury and methyl mercury concentrations in their tissues. Feathers can indicate internal mercury burden and reflect mercury burden at the time they were grown. On Bon Portage Island, Canada, Leach’s Storm-Petrels (Hydrobates leucorhous) are depredated by Great Horned Owls (Bubo virginianus), American Herring Gulls (Larus smithsonianus), and Great Black-backed Gulls (L. marinus), which leave behind severed wings (owls) or regurgitated wings (gulls). This meant we could use flight feathers grown during the nonbreeding season to compare mercury burdens in depredated versus live birds and evaluate if mercury had lasting effects that increased predation risk. We compared concentrations of mercury in fourth secondary (S4) flight feathers of 26 live birds and 35 depredated wing carcasses collected on Bon Portage Island, but found no statistical difference. Our results suggest that neurological effects of mercury depurated during the non-breeding season, at least at the concentrations we observed, do not last long enough to increase petrels’ risk of predation in the breeding season.