05.11.2021 – Airborne followers

The overcast sky didn’t bother our team or guests at all as we set off on to the Atlantic Ocean this morning. Our spotter soon called with sightings, which were obviously marked by a large group of circling Cory’s Shearwaters (Calonectris borealis). Although these birds are one of the most reliable indicators of cetacean activity at sea, things are quite different at this time of the year.

After being spoilt and fattened by their parents all summer, Cory chicks are left to fend for themselves in October/November when the adult birds leave the island, only to return for the breeding season in the following spring. Leaving a nest high up in the cliffs is no piece of cake and is often driven by hunger. Many young Cory’s are often blinded by light pollution along the coastline and bump into things, often injuring themselves in the process. At sea, young Cory’s stick together in their long search for food for safety, so large aggregations may not necessarily indicate cetacean activity.

Today, however, the birds were marking a group of Short-finned pilot whales (Globicephala macerorhynchus) that was briskly travelling east. Unknown to the young birds, these deep-diving dolphins provide little hunting advantages to their airborne followers since they pursue their prey in the deeper parts of the ocean. The birds would have more luck with the Atlantic spotted dolphins (Stenella frontalis), surface active dolphins that, today, were encountered not far from the pilot whales. In the afternoon pilot whales were encountered once again along with a group of Bottlenose dolphins (Tursiops truncatus), wrapping up yet another wonderful day out on the ocean.

By Paula Thake

Sightings of the day

Ribeira Brava

10:00 Atlantic spotted dolphins, Short-finned pilot whales

14:30 Bottlenose dolphins, Short-finned pilot whales