17.10.2026 – Cooperative care

A lot of souvenirs were made on today’s trips ! Sperm whales (Physeter macrocephalus) were passing in front of Calheta and we had the good surprise to see a calf with its mom ! It looked really small compare to its mama but sperm whale’s calves already measure around 4m long at birth. Females have a calf every five to seven years and their gestation period is between 14-16 months. Most females will form lasting bonds with other females of their family, and, on average, 12 females and their young will form a social unit. During birth, females from the pod cluster around the mother to help lift the newborn to the surface so it can take its first breath. Social life is an important part of a sperm whale life and it is a whole team work !

These incredible mammals have one of the most complex, culturally structured societies in the animal kingdom, built on matrilineal family units, shared dialects, and cooperative care. Some of these cooperative cares are shown by baby-sitting behavior where females in the pod stay behind at the surface with the calves while mothers make deep, long foraging dives to hunt giant squids. To stay in contact, rhythmic patterns of clicks called “codas” and each clan uses a distinct dialect, which they pass on across generations.

It is important to understand them better to continue protecting them and their families. 

By Juliette Colançon

Sightings of the day 

Ribeira Brava 

09:00 Short-finned pilot whale, Sperm whale

13:00 Atlantic spotted dolphin, Sperm whale

Steno 

09:30 Atlantic spotted dolphin, Short-finned pilot whale, Sperm whale

13:30 Atlantic spotted dolphin, Loggerhead sea turtle, Sperm whale

16:00 Bottlenose dolphin, Short-finned pilot whale