The season closed officially this week. Twenty-three calves born to twenty-three mother-calf pairs in the southeastern United States from mid-November through mid-April — the highest count since 2009, and the fourth-highest on record [1]. Tuesday's read on the season-end count and inter-calf interval compression named the surface number. NOAA's Wednesday closeout names the structural one.

Of the twenty-three pairs, twenty are returning mothers. Eighteen of those eighteen previously gave birth within the past six years — close to the three-to-four-year interval considered healthy for the species. For most of the past decade, intervals had stretched toward ten years for some females [2]. "Many of this year's moms have had shorter intervals — giving us hope that they may be healthier and can help grow the population faster," said Amy Warren, scientific program officer at the New England Aquarium's Anderson Cabot Center [3].

The headline number is still small in context. Approximately 380 right whales remain, including roughly 70 reproductively active females. Reversing population decline would require about 50 calves per year sustained over multiple seasons, according to researchers at the Canadian Whale Institute. The 2018 season produced zero known calves.

The structural news lives below the count. The 2026 season also recorded approximately 500 sightings of 129 right whales in the Southeast — more than a quarter of the population, a 29 percent increase over last season's southern-grounds presence. One mother-calf pair was spotted in the Gulf of America for the sixth time since 2000. Calving-ground occupancy, like calving interval, is recovering. The season closed; the demographic question stayed open.

-- KENJI NAKAMURA, Tokyo