14.10.2019 – The deep blue interface

The surface of the Atlantic Ocean is a distinct blue boundary, an interface separating the elements. With dolphins you get the best of both worlds; they are magnificent to meet both at and below the surface.

During our tours the majority of our sightings occur at this interface like the brief one involving Bottlenose dolphins (Tursiops truncatus) this morning that were discreetly travelling in the waters outside Madalena do Mar. However, since this tour was actually a snorkelling tour aimed to provide sightings below the surface, we soon veered west after our spotter announced a calm group of our cheeky summer dolphins, the Atlantic spotted dolphins (Stenella frontalis).

Of course our zodiac sped to the area and our participants were soon surrounded by the curious, nimble little dolphins. I’ve mentioned this countless times in my blogs but I’ll say it again; sightings below the surface really are something else and allow a glimpse into the mysterious world of these highly intelligent creatures. Dolphins generally never make a quiet entrance,  you usually hear them way before you actually see them. As they draw near the buzzes, clicks, squawks and squeaks are amplified and these vocalizations aren’t just heard, they can also be  felt. It is in fact not unusual to feel mini tremors in your chest when being scanned by their acute sonar. 

The surface of the Atlantic Ocean is like a door into the great unknown for human beings but for dolphins it is a vast habitat. They move freely above and below it, between the air and the water and have mastered the use of both elements. Most fish do not have that luxury and will not leave the safety of the ocean to expose themselves to lurking predators at the surface, particularly marine birds. The only fish that have mastered escape from predators in the water by completely breaching the surface are the Flying fish. The Atlantic flying fish (Cheilopogon melanurus) in Madeira are often seen propelling themselves out of the water and gliding for an incredible amount of time at the surface through the rapid movement of their wing-like pectoral fins. We were able to briefly witness a small group of juvenile flying fishing doing this today, probably as an evasive maneuveur because they mistook our zodiac for a large predator.

So in conclusion, whether you’re on or in the water, the surface of the Atlantic Ocean sure is an exciting place..and I have no doubt that our snorkelers today will concur!

By Paula Thake

Sightings of the day

Stenella 

10:00 Atlantic spotted dolphins, Bottlenose dolphins