North Atlantic Right Whales: Climate Refugees

Climate change is causing freshwater glaciers at the planet’s poles to melt. As a result, the salinity and density of ocean water are diminished, which prevents cold currents from flowing as deeply as they did before. This reduces the velocity of Atlantic currents, including the Gulf Stream. Its course has deviated from the historical norm, and its warm waters are entering into new areas such as the deep waters of the Scotian Shelf. This disturbance subsequently causes these regions to grow warmer, creating unfavourable conditions for C. finmarchicus, which is only able to thrive in cold water. The fact that population levels of this small copepod remain abnormally low may be having a significant impact on these black giants, such as causing them to starve or driving them to new territories in search of food.

According to the study conducted by Meyer-Gutbrod and her colleagues, the decline in C. finmarchicus stocks has been pushing North Atlantic right whales out of their traditional summer feeding grounds since 2010. These include the Gulf of Maine and the Bay of Fundy, both of which are part of the Scotian Shelf. The whales have abandoned these regions in favour of other sectors, notably the Gulf of St. Lawrence.

The changing behaviour of North Atlantic right whales is creating new hurdles for conservation efforts. Not only did the whales have to abandon their traditional feeding grounds, but their recent presence in the Gulf of St. Lawrence is causing major conflicts with the fishing industry and maritime traffic. Although collisions with vessels and entanglements in fishing gear have been known for decades to be significant causes of mortality in North Atlantic right whales, the measures and regulations put in place on the east coasts of Canada and the U.S. were not in effect in the Gulf of St. Lawrence when right whales first appeared there. A protection program was not put in place by the Canadian government until the summer of 2017, when a record number of mortalities was observed.

According to the authors of the study, current monitoring and protection projects for the species have greatly improved forecasts of the animals’ movements, in addition to providing much more detailed tracking than was possible before. However, it is difficult to predict whether the right whales’ new summer habitat and the emergency protection measures implemented there will be sufficient to prevent the extinction of these climate refugees.