Potential impacts of offshore oil spills on polar bears in the Chukchi Sea

Abstract

a b s t r a c tSea ice decline is anticipated to increase human access to the Arctic Ocean allowing for offshore oil and gas development in once inaccessible areas. Given the potential negative consequences of an oil spill on marine wildlife populations in the Arctic, it is important to understand the magnitude of impact a large spill could have on wildlife to inform response planning efforts. In this study we simulated oil spills that released 25,000 barrels of oil for 30 days in autumn originating from two sites in the Chukchi Sea (one in Russia and one in the U.S.) and tracked the distribution of oil for 76 days. We then determined the potential impact such a spill might have on polar bears (Ursus maritimus) and their habitat by overlapping spills with maps of polar bear habitat and movement trajectories. Only a small proportion (1 e10%) of high-value polar bear sea ice habitat was directly affected by oil sufficient to impact bears. However, 27e38% of polar bears in the region were potentially exposed to oil. Oil consistently had the highest probability of reaching Wrangel and Herald islands, important areas of denning and summer terrestrial habitat. Oil did not reach polar bears until approximately 3 weeks after the spills. Our study found the potential for significant impacts to polar bears under a worst case discharge scenario, but suggests that there is a window of time where effective containment efforts could minimize exposure to bears. Our study provides a framework for wildlife managers and planners to assess the level of response that would be required to treat exposed wildlife and where spill response equipment might be best stationed. While the size of spill we simulated has a low probability of occurring, it provides an upper limit for planners to consider when crafting response plans.Published by Elsevier Ltd.

A State‐of‐the‐Art Review of Indigenous Peoples and Environmental Pollution

“…Indigenous peoples inhabit some of the most ecologically undisturbed areas of the world, often of outstanding biodiversity importance (Garnett et al 2018). Thus, pollution in IP lands has an uneven and significant impact on critical environments, affecting large numbers of wildlife species (Basu et al 2009; Wilson et al 2018). While the impacts of pollution on ecosystems and biodiversity have been studied extensively (Taylor et al 2016), particularly in aquatic systems (Desforges et al 2018), accumulated evidence of these impacts comes primarily from industrialized nations, with a strong focus on consequences of agricultural intensification and industrialization.…”

Comparative review of the distribution and burden of contaminants in the body of polar bears

“…PACs biodilute, which means that their concentrations decrease with higher trophic level due to the increase of biotransformation rate (De Laender et al, 2011). Recently, modelling of oil spill's impact on polar bears was calculated and it was found that around 27-38 % of polar bears from the Chukchi sea region would be affected (Wilson et al, 2018). Indeed, it was noted that oil spills could probably reach important habitats for polar bears, such as areas of denning or summer terrestrial habitats (Wilson et al, 2018).…”

Crude oil exposure reduces ice algal growth in a sea-ice mesocosm experiment

“…Oil spills in the Arctic will affect the entire food web. Model studies suggest, for example, that oil spills can expose large fractions of populations of polar bears to released oil in the Chukchi Sea (Wilson et al 2018) and causes different risks to other animals, like ringed seals and walrus, based on an oil spill risk assessment for the Kara Sea (Helle et al 2020). Arctic sea birds are also sensitive to oil pollution as demonstrated in the high mortality of guillemots and little auks off Newfoundland caused by ship-source oil pollution (Frederiksen et al 2019).…”