During our last late afternoon trip we had the chance to witness first hand how unpredictable are the waters around São Miguel Island. Our journey started really well: glassy Ocean and perfect visibility…not even a few hundreds meters from the Ilheu da Vila Franca and we were surrounded by a group of Common Dolphins. We could see several calves, one of them was just a neonate as the lateral fetal folds were clearly visible. These folds are caused by the position in which the fetus is during the gestation period and generally disappear in about two weeks from the birth.

As we left the dolphins resting close to the Ilheu, we spotted two Beaked Whales (Mesoplodon spp), most likely Blainville’s (Mesoplodon densirostris). These elusive creatures generally dive in a minute from being sighted but in this case they kept travelling at slow pace and surfaced about twenty times in front of our boat. If you wish to have more info about this species, you can check our previous post here!

 

Beaked Whales (Mesoplodon spp) surfaces next to Terra Azul boat. The apparent lack of two teeth protruding from the lower jaws suggests that these two individuals are females. Males of Blainville’s Beaked Whales (Mesoplodon densirostris) have two distinctive “tusks” erupting from the middle lower jaws (Source: NOAA Fisheries). Tusks are probably used during intraspecific interactions with other males to establish breeding hierarchy and are responsible of the extensive body scarring observed in adult males. Another typical feature of beaked whales is the absence of a notch in the fluke.

 

One of the two of Beaked Whales (Mesoplodon spp) encountered has a notch on its dorsal fin that can be used to photo-identify this individual. Such information is extremely valuable to better understand the distribution of cryptic species that spend most of their lives in the depths.

 

With no whales in sight for our land spotters, we continued our survey stumbling across several Loggerhead Turtles (Caretta caretta) and making our way home, hitting the coast around Ribeira Quente. Our guest was just mentioning that she was wearing her “lucky shirt” for this trip when we saw a splash not far from us… the sunlight from the West did not help understanding what kind of fins we were looking at, they all seemed to be black. And they were black indeed! A pod of about 60 False Killer Whales (Pseudorca crassidens) was slowly cruising along the coast with a front stretching for 300 meters. A couple of them seemed to be extremely curious about us and came to bow ride our boat, looking at us every now and then with their eyes wide open. In those light-blue iris eyes I could almost see the same curiosity that I, as many other scientists, have for these creatures. And if you are curious too, you can check our post about this species here!

 

An adult False Killer Whale (Pseudorca crassidens) rides alongside Terra Azul boat.

 

Our False Killer Whale (Pseudorca crassidens) “escort” keeps travelling West while we sadly (and late!) have to return to our “reality”.

 

 

What to add, that shirt is lucky indeed!

Lorenzo Fiori

About Lorenzo Fiori

Lorenzo is Main Guide and Technical & Scientific Director at TERRA AZUL. He is originally from Italy, holds a Science Master in Biology, and is completing PhD about behavioral responses of humpback whales to swim-with-whales tourism activities in Tonga.

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