Endangered North Atlantic Right Whales Have Their Best Calving Season Since 2009

With a population of only around 380 individuals, the North Atlantic right whale is one of the most endangered large whales on the planet, and every birth matters enormously. So when the 2025–2026 calving season wrapped up with 23 documented calves, the news rippled through the marine science community as a genuine reason for hope. It was the highest tally since 2009 and among the strongest seasons ever recorded for the species.

The calving season runs from roughly mid-November to mid-April, and mothers gather each winter in the warm coastal waters off the southeastern United States to give birth. This year the pattern of births was especially encouraging: 18 of the 23 mothers had produced a calf within the previous six years, and three were first-time mothers, a sign of new breeding females entering the population. The mix suggests that reproductive activity is broadening rather than resting on a handful of familiar individuals.

“So when the 2025–2026 calving season wrapped up with 23 documented calves, the news rippled through the marine science community as a genuine reason for hope.”

Researchers were quick to put the numbers in context. “While a healthy right whale can give birth every three to four years, we had been seeing nearly 10 years between calves for some females,” explained Amy Warren, a scientific program officer at the New England Aquarium. A tightening of that interval matters because it points to whales in better condition — able to store the energy reserves that pregnancy and nursing demand. Among the mothers this season were two elder matriarchs, Juno and Ghost, both more than 40 years old and each with at least nine calves to their name.

The calves did not stay south for long. As spring arrived, mothers and young began their northward migration, and at least 18 pairs were later documented in Massachusetts waters, with more than a third of them gathering in Cape Cod Bay. The season is a heartening step, but scientists stress that right whales still face grave threats from entanglement in fishing gear and collisions with vessels. A strong crop of calves buys the species time — and a reminder that, with continued protection, even a whale on the edge of extinction can keep bringing new life into the sea.