World’s oldest porpoise celebrates 31st birthday with underwater cake

The world’s oldest known harbour porpoise, Freja, marked her 31st birthday on Tuesday at the Fjord & Belt research centre in Kerteminde, Denmark—an age five times longer than her wild counterparts, DR reports.

Harbour porpoises in the wild typically live five to seven years, with human-made noise from shipping and wind farms, as well as lung parasites, contributing to their shorter lifespans. Freja’s longevity is attributed to veterinary care and a controlled environment, according to Christina Andersen, head of the training department at Fjord & Belt.

“Given the average lifespan, having her here is really extraordinary,” Andersen said.

Freja was accidentally caught in a fisherman’s net in 1997 at age two and has lived at the centre ever since. Over the decades, she has participated in numerous research projects on porpoise behaviour and biology, making her one of the most studied cetaceans in the world.

To celebrate, staff prepared a frozen “cake” made of gelatine—a treat that also helps meet the mammals’ freshwater needs. Freja will share the cake later in the day with her two tankmates, seven-year-old porpoises Saga and Eskild.

“She’ll get a little something extra today,” Andersen said.

While Freja’s exact future lifespan remains unknown, she currently holds the record as the oldest porpoise in captivity. Whether she will break her own record next year “remains to be seen,” Andersen added.