How long can North Atlantic right whales live? Scientists may finally have an answer

North Atlantic right whales currently live only about 22 years, but a new study finds they could live over 130 years.

Researchers at the University of Alaska, Fairbanks and other institutions involved in the study say only 10% of North Atlantic right whales live to be 47 years old. The average age at death for the species is around 22 years.

In contrast, south Right whales, a closely related species, have a median life expectancy of about 73 years, and 10% are expected to live to nearly 132 years.

“So we can compare how North Atlantic right whales are doing compared to these other species and see that something is terribly wrong,” said lead author and researcher Greg Breed. “And I think the terribly wrong things are staring us in the face.”

Breed says entanglements in fishing gear, boat collisions and climate change are responsible not only for the North Atlantic population’s decline to about 370, but also for the fact that right whales now live relatively short lives.

The paper, which relies on models based on long-term sighting data, also argues that centuries of whaling have killed all of the older whales in the North Atlantic right whale population, so current forest data does not reflect true longevity potential.

“It could be another hundred years before ancient individuals are seen again,” Breed said, “or even exist again for us to discover.”

The consequences of a young population are serious, researchers said.

“Animals that live long can withstand annual environmental changes, including variations in prey, habitat, oceanography and climate. Going through difficult times allows animals to conserve resources to survive and reproduce when they get better, said Scott Kraus, a scientist emeritus at the New England Aquarium. WCAI asked him to independently review the paper.

Shortened lifespans cause North Atlantic right whales to suffer in many ways as a species. Because there are few or no older whales in populations, there is less “generational knowledge” about how to stay alive when conditions change. And a short lifespan results in dramatically lower potential for reproduction and population renewal, especially compared to southern right whales.

“Southern right whales reach maturity at 12 years old, just like North Atlantic right whales, but they live to 74 years and calve every three years. Well, if you do the math, an average individual … will have about 15 (calves), compared to two, three or four for the North Atlantic right whale,” Breed said. “And that just makes a big difference in population trends.”

Kraus described the paper, published Friday in the journal Science Advances, as a “compelling case” that “goes far beyond the prevailing wisdom on whale longevity.”

“This paper is an excellent and quantitative reminder of the unintended costs of doing business in the ocean,” he said, “and an exclamation point on the steady stream of scientific information that has emerged over the last decade showing that North Atlantic right whales are at risk of extinction. “”

This story is a production of the New England News Collaborative. It was originally published by CAI.