It wasn’t easy for our spotter to find animals for our crew at sea today and both our boats had to travelled far to the sightings area today….but it was definitely worth it! Both our boats travelled to the waters of Cabo Girão to meet a group of Sperm whales (Physeter macrocephalus) that were in the middle of socialising at the surface. These gentle giants make sure to use their time at the surface wisely and spend it socialising or blissfully resting and preparing for their next deep foraging dive. Our traditional boat even managed an encounter with Short-finned pilot whales (Globicephala macrorhynchus), a species that displays a similar social structure to that of the Sperm whales. In the case of both species, males and females differ in their life cycles with females remaining with their birth pod and nurturing a matriarchal social structure whilst males leave and often form groups with other males. As they age, Sperm whale bulls even resort to a more solitary lifestyle and wander across the oceans as nomads.
The social structure typical for Blainville’s beaked whales (Mesoplodon densirostris), the timid species that was encountered this afternoon, is quite different. Despite the little that is known about the social life of beaked whales, it is assumed that Blainville’s beaked whales live in harem structures, with an alpha male protecting and leading his group of females. The deep scars and emerging tusks that are characteristic for the bulls are reminiscent of competitive fights that may occur between males over their female groups.
Even though these deep divers forced our boats to venture far today and often are tricky for our spotter to keep track of, the journey was absolutely worth it!
By Paula Thake
Sightings of the day
Ribeira Brava
10:00 Short-finned pilot whales, Sperm whales
14:30 Blainville’s beaked whales
Stenella
10:00 Sperm whales