Scientists are feeling encouraged by a spate of early-in-the-season sightings of the critically endangered North Atlantic right whales in the waters south of Massachusetts. Reports of the returning population have since triggered a voluntary slow zone for ships in the area.

A group of eight right whales were first spotted on 5 January, when scientists from the New England Aquarium’s Anderson Cabot Center for Ocean Life were flying an aerial survey about 30 miles south of Cape Cod, Massachusetts. Three days later, on 8 January, more than 20 right whales were sighted. 

The winter to spring marks the peak time of year for right whale sightings in southern New England waters. Sightings of this critically endangered species so early in the season have left scientists feeling enthused.

“All around us, we saw groups of whales rolling, splashing, and bursting out of the water,” said Kate Laemmle, an assistant scientist at the Anderson Cabot Center for Ocean Life and one of the observers on the survey plane. She was left particularly excited by the high number of social right whale groups in a tightly concentrated area.

“Seeing these critically endangered right whales on our first surveys of the New Year is a great way to start the season and leaves us hopeful for more whales returning to the area,” she added.

With just 360 individuals remaining, the North Atlantic right whale has been listed as endangered under the Endangered Species Act since 1970. 

The sighted-group included at least 23 unique whales, including two female right whales who have calved in recent years, and three who may be nearing calving age. As it stands, there are only 70 reproductively active female North Atlantic right whales remaining.

The three females nearing calving age were all seen in surface active groups – a social behavior that involves several right whales closely interacting at the surface. These surface active groups can also provide mating opportunities. 

The sightings triggered the National Oceanic and Atmospheric Administration to implement a voluntary slow speed zone for mariners to reduce their speed to 10 knots to protect the whales. This will be in effect until 20 January.

Vessel strikes are a primary due threat to the species since the whales spend a lot of their time at or close to the water surface. Their dark colour and lack of dorsal in also makes them notoriously difficult to spot – particularly in bad weather, murky water and low light. 

Katherine McKenna, Associate Scientist in the Aquarium’s Anderson Cabot Center was aboard the 8 January survey flight. 

She said: “Reducing vessel speed in mandatory and voluntary right whale management areas is one of the most effective actions mariners can take to reduce the risk of vessel strikes and help protect this critically endangered species.”

Click here for more from the Oceanographic Newsroom.