The right whale ( Eubalaena glacialis ) is a critically endangered species by the Red List of Threatened Species of the International Union for Conservation of Nature and, in view of a work published in Oceanography magazine, the prospects are not very flattering. According to the study, the warming of the oceans has driven these animals out of the North Atlantic, which until now has been their traditional and protected habitat. As a consequence, whales are now more exposed to all kinds of dangers such as being caught in fishing nets or colliding with a boat. If something is not done, the authors predict, the right whale population will decline and likely become extinct in the coming decades.
Since 2010, the calving rate has decreased and the right whale population has declined by about 26%, according to the study. At the beginning of the decade, the North Atlantic right whale population exceeded 500. Now the North Atlantic Right Whale Consortium estimates the population to be only 356 whales.
Gulf of Maine warming
According to the authors, rising temperatures have changed ocean circulation patterns in the North Atlantic, including currents that flow deep into the Gulf of Maine. Warming in this area has reduced the abundance of copepods, tiny crustaceans that serve as food for right whales. This has reduced calving rates and forced the whales to abandon their mid-summer foraging grounds in the Gulf of Maine to head north to the colder waters of the Gulf of St. Lawrence where no protective measures exist. to avoid collisions with boats or entanglement with fishing gear.
This has led to an Unusual Mortality Event declared by NOAA in 2017, when 17 right whale kills were confirmed, mainly in the Gulf of St. Lawrence. Ten right whales were found dead in 2019, while for 2020 and 2021, there have been four deaths so far. “Right whales continue to die every year,” says lead author Erin Meyer-Gutbrod, an assistant professor at the University of South Carolina. “Protection policies must be strengthened immediately before this species declines beyond the point of no return.” Ocean scientists hope for new policies on ropeless fishing gear, enforcement of boat speed limits, and money for monitoring and predicting ecosystem evolution.
Referencia: Meyer-Gutbrod et al. 2021. Ocean Regime Shift is Driving Collapse of the North Atlantic Right Whale Population. Oceanography https://doi.org/10.5670/oceanog.2021.308
