Polynyas and the D’Urville Sea Ecosystem
The D’Urville Sea, located west of Ross Sea in the easternmost part of the East Antarctic, is the best studied region of the East Antarctic and a critically important area for Antarctic predators. Productivity in the region is driven by coastal polynyas, as they occur in the same spots year after year, providing consistent access to productive waters where predators can forage.
Top Predators
The D’Urville Sea region supports an amazing array of predators, including Weddell and leopard seals, South polar skuas, snow petrels, Wilson’s storm petrels, giant petrels, cape petrels, southern fulmars, and Adélie and emperor penguins. This includes the world’s most famous colony of emperor penguins from Point Géologie, which were featured in the March of the Penguins. This colony’s proximity to the French Dumont D’Urville Station means we have long-term data (six decades) to track how these penguins are responding to climate change.
Climate Change
Climate change is a major threat to this region. Emperor penguin colonies in the vicinity of the D’Urville station are predicted to drastically decline in the future, mostly due to declines in their sea ice habitat. While Adélie penguin populations are predicted to be relatively stable into the future, climate change remains a looming threat. A colony of Adélie penguins at Terra Adélie in the D’Urville Sea experienced complete breeding failure twice in the last decade.
This failure was likely due to the absence of the ususal polynya nearby, which did not form in those two years due to changes in the regional winds. Thus, the adult penguins were not able to access open water to forage and bring food back to their chicks. These sad events highlight the critical importance of polynyas in providing feeding grounds during vulnerable parts of a penguin’s life cycle.
Conservation
The D’Urville region is currently proposed for protection, as part of a representative system of marine protected areas (MPAs) across the whole East Antarctic region. The proposed D’Urville Sea MPA would protect and monitor foraging areas for Adélie and emperor penguin colonies, which are critical during their breeding and chick rearing seasons. The MPA would also provide a reference area for better understanding the impacts of climate change, and could provide for stronger management in this vulnerable region.
