Could sea ice help predict the survival of Arctic hooded seals?

SFU Environmental Scientist teams up with researchers from the Centre National de la Recherche Scientifique and La Rochelle Université in France to investigate the impacts of melting sea ice on ecology and food accessibility for Indigenous communities in the eastern Arctic.

Arctic temperatures have been warming three times faster than the global average, resulting in a decrease in sea ice thickness and salinity. This leads to a sinking of the mixed layer depth where vital nutrients for marine wildlife are stored. The effects these climbing temperatures will have on sea ice, on ice-dependent seals at the top of the Arctic marine food web and on Indigenous communities who have historically hunted these species are unclear.

Ruth Joy, a statistical ecologist in Simon Fraser University’s School of Environmental Science will work alongside French researchers investigating the impacts of a continuous loss of sea ice on Arctic hooded seals which are a threatened species according to the International Union for Conservation of Nature (IUCN). These seals dive at depths of more than 1,000 meters for durations of more than an hour. Given that many diving seals have strong affinities for specific vertical structures that drive their vertical habitat use, this work aims to incorporate sub-surface oceanographic variables into species habitat models to get a more realistic picture of the distributional shifts that diving animals might experience under climate change scenarios.

With a 30-year archive of hooded seal movement data and over $100,0000 from the France Canada Research Fund and the Ministry of Higher Education, Research and Innovation, the group will look at how sea ice has moved and fluctuated in quantity and quality over recent decades, and how hooded seal movements and behaviour have changed in response.

“If seals are having to swim longer and to deeper depths to feed because their food source is deeper, and are shifting foraging to different areas, it has implications for seal survival and potentially human survival—or at least on Indigenous access to traditional food sources,” says Joy.

The team will first characterize vertical foraging behaviour of hooded seals, and then assess changes therein across the past 30 years in the eastern Canadian and European Arctic, and what gaps in this data remain.

“There is a lot of Indigenous knowledge about ice seal habitat use and behaviour (e.g. spatial distribution, timing of presence, habitat association, diving and foraging behaviour) that could be used to understand ice seal species’ response to climate change” says Joy.

Joy and her team will look to incorporate indigenous knowledge like this and develop a modelling and forecasting framework that combines this data at varying time and spatial resolutions. As the project progresses, the team hopes to integrate Indigenous perspectives to better understand how the future of hooded seals may impact Arctic communities.

Ultimately, the team is looking to better understand both the current state of ecology and food accessibility for Indigenous communities in the eastern Arctic, and what we can expect as temperatures continue to rise.