Arctic sea ice meltdown leaving marine mammals' future uncertain

 

 

For Arctic marine mammals, the future is especially uncertain. Loss of sea ice and warming temperatures are shifting already fragile Northern ecosystems. The University of Washington study, assessing the status of all circumpolar species and subpopulations of Arctic marine mammals, including seals, whales and polar bears, underscores the precarious state of those mammals and outlines the current state of knowledge and their recommendations for the conservation of these animals over the 21st century.

 

Lead author Kristin Laidre said that these species are not only icons of climate change, but they are indicators of ecosystem health, and key resources for humans. The overall numbers and trends due to climate change are unknown for most of the 78 populations of marine mammals included in the report: beluga, narwhal and bowhead whales; ringed, bearded, spotted, ribbon, harp and hooded seals; walruses; and polar bears.

 

Accurate scientific data, currently lacking for many species, will be key to making informed and efficient decisions about the conservation challenges and tradeoffs in the 21st century, said Laidre. The species most at risk from the changes are polar bears and ice-associated seals. Laidre said that these animals require sea ice to find food, find mates and reproduce, to rear their young. It's their platform of life. It is very clear those species are going to feel the effects the hardest.

 

Whales may actually benefit from less ice cover, at least initially, as the open water could expand their feeding habitats and increase food supplies. Approximately 78 percent of the Arctic marine mammal populations, included in the study, are legally harvested for subsistence across the Arctic.

 

There's no other system in the world where top predators support human communities the ways these species do, Laidre said.

 

Among the few recommendations are maintaining and improving co-management with local and governmental entities for resources, recognizing variable population responses to climate change and incorporating those into management, improving long-term monitoring while recognizing monitoring for all species will be impossible, studying and mitigating the impacts of increasing human activities and recognizing the limits of protected species legislation.