Nova Scotia

New population estimate for right whales at its lowest in 20 years

Researchers said Monday that they estimate there are just 336 North Atlantic right whales left on the planet. Entanglements in fishing gear and vessel strikes are among the biggest threats to the endangered species.

Researchers estimate there are 336 North Atlantic right whales left on the planet

An aerial shot of a North Atlantic right whale.
Researchers estimate there are 336 North Atlantic right whales remaining on the planet. (Peter Duley/NOAA Fisheries Northeast Fisheries Science Center)

A new estimate of the number of endangered North Atlantic right whales left on the planet puts the population at 336, the lowest in nearly 20 years.

The figure, which represents the 2020 population, is down eight per cent from the previous estimate of 366 in 2019, and is far below the peak of 481 in 2011.

The North Atlantic Right Whale Consortium, a partnership of nearly 40 organizations with an interest in protecting the species, said the cause of the decline is clear.

"There is no question that human activities are driving this species toward extinction," Scott Kraus, the chair of the consortium, said in a news release Monday morning.

Entanglements in fishing gear and vessel strikes are among the biggest threats to the survival of the North Atlantic right whale.

The estimated number of North Atlantic right whales is on the decline and is at the lowest point in about 20 years. (The North Atlantic Right Whale Consortium)

Research by the New England Aquarium has shown that 86 per cent of identified right whales have been entangled in fishing gear at least once.

In recent years, the Canadian government has implemented changes in the shipping and fishing industries to reduce entanglements and collisions between ships and whales, including periodic closures of certain fisheries and mandatory speed limits for vessels in the Gulf of St. Lawrence.

Philip Hamilton, a senior scientist with the New England Aquarium, said even more needs to be done. He said ropeless fishing gear and using ropes with less strength can reduce the likelihood that a whale will be killed or hindered by entanglements.

Adding speed restrictions for smaller vessels may also help, he said, noting that last winter, a mother and calf were hit by a smaller recreational vessel, killing the calf and injuring the mother. 

'There is hope'

Aside from the moral imperative simply to be good stewards of the planet and its inhabitants, Hamilton said humans should want to protect North Atlantic right whales because they play an important role in the ocean's ecosystem.

The mammals feed deeper in the ocean and excrete at the surface, feeding the plankton at the bottom of the food chain and therefore helping all the other ocean species, including the ones that humans eat. 

"If we want to be anthropocentric, if we like, you know, having seafood, then we don't know exactly what the impact of removing large whales [will be], but we know it won't be good," Hamilton said.

Piles of fishing rope lie on a wharf. Entanglement in fishing gear is one of the main causes of death and poor health in North Atlantic right whales. (Fundy North Fishermen's Association)

Hamilton said he does believe it's possible for the North Atlantic right whale population to bounce back, as it has before. The population of the species was estimated at 265 in 1990.

"Right whales are a very resilient species. They've come back from much lower numbers than this in the past, probably at least twice, and so we know that they can. The question is whether or not we'll be able to implement really effective management efforts to … stop killing them and also minimize the impact of sublethal effects," he said.

"So don't toss in the towel on these guys. Let's just keep working toward a solution that will help them and hopefully help the rest of the ocean." 

Scientists tracked 18 mother-calf pairs this year, a figure that's down from the annual average of 23 over the past decade. Researchers estimate there are fewer than 100 breeding females alive.

There were just two documented mortalities, but scientists estimated that only about 36 per cent of mortalities are usually detected.