24.04.2025 – Speckled, mottled and fused

There are cetaceans that are relatively difficult to observe at sea because of their typical behaviour towards boats. Atlantic spotted dolphins (Stenella frontalis) aren’t one of them. These small cetaceans are renowned for their inquisitive, fearless behaviour making them a favourite amongst whale-watchers and researchers alike.

While the interactive behaviour is the primary reason our guests love them, scientists appreciate these dolphins for many other reasons which are mainly related to their name giving feature: the characteristic spot pattern. This pattern can be classified into age-dependent phases, which allow scientists to identify different age groups in the pod, which helps better understand the groups social dynamics. The spot phases are known as two-tone (a uniform gray/white colouring until the age of 3-4), speckling (a collection of freckles near the beak 3-5 years), mottled (at 8-9 years when animals have merging grey and white spots on their dorsal side) and fused, the final stage where mature animals gain white spots on a dark surface.

Beyond providing this valuable information, the spot pattern can also be used as an ID feature for biologists along with the animals dorsal fin. So these dolphins provide ample information on both their social dynamics as well as their distribution patterns.

These wonderful dolphins were encountered on all our tours today, delighting both crew and guests with their undeniable charm and informative spot pattern.

By Paula Thake

Sightings of the day

Ribeira Brava

09:00 Atlantic spotted dolphins

13:00 Atlantic spotted dolphins

Stenella

09:30 Atlantic spotted dolphins

13:30 Atlantic spotted dolphins

16:00 Atlantic spotted dolphins