In the waters surrounding Madeira and ranging as all the way across the Atlantic, you may find the Atlantic spotted dolphin (Stenella frontalis). It is a graceful animal, curious, friendly and always up for a little fun. They glide so playfully in the water in front of our bow and may even jump out of the water sometimes, right by our boat, where a skilled photographer has the opportunity for some fantastic pictures, if he’s quick enough. But not all of this behaviour is merely fun. A dolphin that leaps straight up out of the water, could be doing one of several things: having a little look, playing or just spending energy, some researchers suggest that a large whale’s breach could be a signal that scares fish into tight schools, easier to hunt. But in this case, it is most likely a social behaviour, a loud smack on the water is even louder under water where sound travels four times faster. This means that the entire group hears the big splash, it is a non-verbal signal, and even though scientists are still speculating the exact meaning, it is at the very least a signal that will not be missed, by anyone in the water, or on our boat.
Dolphins of course do not only communicate via non-verbal signals, they are quite active verbally, those of us that went into the water today probably heard, but sometimes even the people on the boats may hear the clicking and whistling sounds. As these extremely social animals are constantly discussing things, where to hunt, where to travel, how the social hierarchy changes within the group, perhaps even what types of fish they prefer or perhaps about those silly humans they met today.
One other interesting occurrence today was worth noting, a Loggerhead turtle (Caretta caretta), saw our boat and dove down, we managed to follow it under water for a little while, where it seemed oddly shiny. Our under water video showed a small school of fish swimming along, enjoying the algae and other food on a turtle shell. By their black and white stripe pattern they were most likely a species of Pilot fish (Naucrates doctor).
With the help of our excellent spotter, every boat managed to get to the right spot to see the spotted dolphins, his directions were spot on as always .The dolphins that welcomed us into their home today were a wonderful sight and fantastic experience, we keep our eyes on the horizon, to see what we may find next.
By Scott Dorssers
Sightings of the day
Ribeira Brava
09:00 Atlantic spotted dolphin
13:30 Atlantic spotted dolphin
Stenella
09:00 Atlantic spotted dolphin (Snorkeling)
15:30 Atlantic spotted dolphin
