Abstract for: The Mednyi Mystery: An Hypothesis for the Collapse of an Arctic Fox Population Due to Removal of Human Predation
Over the decade of the 1970s, following the end of the presence of human fur trappers on Mednyi Island, a small Russian island off the coast of the Kamchatka Peninsula, the indigenous population of arctic fox (vulpes lagopus) declined precipitously. This collapse is typically attributed to an outbreak of mange in juvenile foxes, though the cause of the outbreak and influence of factors like levels of mercury pollution in the environment are not well understood. However, recent surveys of the fox population have found no evidence of residual mange pathogens in the current population, and mercury levels in modern juvenile foxes is believed to be lower than the levels found in museum specimens of juvenile furs that were harvested prior to the population collapse. This paper offers a mathematical model expressed in the System Dynamics language hypothesizing a causal connection between the departure of humans and the subsequent collapse of the fox population. This model also demonstrates why it might be that no mange pathogens are present in the current population and how levels of mercury pollution in juveniles may have declined as the population collapsed.