Record-Breaking Bowhead Whale Sets New Pregnancy Duration at 23 Months

Bowhead whales, known for their long lifespans and slow growth, may have the longest known pregnancy in mammals, lasting up to 23 months. Researchers studied samples from 10 female bowhead whales and analyzed hormone concentrations in their baleen, revealing two surges in progesterone that suggested either a 23-month pregnancy or a prolonged state of estrus followed by a 14-month pregnancy. The findings shed light on the complexities of bowhead whale reproduction and could aid conservation efforts for this vulnerable species.