A Forensic Evaluation: the use of Mercury and Stable Isotope analysis of Museum Bone Samples to Monitor if Environmental Changes are affecting the Eating Patterns of Red and Arctic Foxes

Abstract

Global climate changes can potentially impact the ecosystems of the red foxes (Vulpes vulpes) and Arctic foxes (Alopex lagopus) on a regional scale. This research takes a forensic approach at investigating certain health and dietary indicators in museum preserved bone of red foxes of Bethel Alaska and Arctic foxes from the Yukon Territory in Canada. This study attempts to 1) measure the mercury (THg) concentration levels, 2) estimate a diet using carbon stable isotopes (δ13C) and 3) establish a trophic level using nitrogen stable isotopes (δ15N), from bones of these sentinel species. This study examines two Arctic foxes and three red foxes of unknown age and origin. The Yukon Territory Arctic foxes bone THg concentrations were 0.017 and 0.025 mg/kg. The red foxes bone THg concentrations were 0.010, 0.036 and 0.073 mg/kg. The δ13C levels were -21.13 and -21.36‰ for Arctic foxes and -20.05, -20.08, and -23.12‰ for red foxes. Their δ15N levels were 5.59 and 7.22‰ for the Arctic foxes and 6.10, 6.57 and 6.66‰ for red foxes. These Arctic and red Yukon Territory foxes indicate a trophic level similar to Arctic terrestrial omnivores. This type of forensic study is useful to establish past ecosystems of the Arctic. In understanding past ecosystems we can then monitor the effects of climate change and its impact on human health and the health of terrestrial animals.