Terra Azul boat hydrophone gets closely inspected by three curious Sperm Whale (Physeter macrocephalus) calves. Picture credit: Guillaume Choquert.


What a beginning of September on São Miguel waters!!!


Today we started our adventure at sea encountering a super pod of hundreds of Common Dolphins (Delphinus delphis). The group was so large that we could see dolphins until our eye reach towards the East side of the island. We estimated that there were more than 500 individuals in the area, most of them chasing some fish accompanied by Cory’s Shearwaters (Calonectris borealis).


Common Dolphins (Delphinus delphis) hunting near Ribeira Quente, São Miguel Island.


Then we moved a few miles off-shore where our vigia spotted some blows. Another Terra Azul boat was already on the spot and we could see a large adult Sperm Whale (Physeter macrocephalus) taking a dive to feed. Three calves of different ages stayed at the surface as most likely they are still too young to follow the adults in the depths. Until they are able to dive and hunt for squids, calves spend most of their time socializing and exploring the surface world while their mothers are foraging. Feeding dives here in the Azores last an average of 40-45 minutes, so there is plenty of time for young whales to look for distractions around. These three calves seemed to find our boat and guest quite interesting and they start swimming toward us!


The three calves of Sperm Whale (Physeter macrocephalus) approaching Terra Azul boat.


Our skipper slowly moved the boat out of their way and downwind to avoid drifting towards them. We could see them passing by in front of our bow and we dropped the hydrophone to hear if they were vocalizing. That’s when something incredible happened!

The trio appeared to find the hydrophone extremely interesting and suddenly converge to it producing a storm of echolocation clicks directed first to the boat and us, and then straight to the device itself!!! The result in our speakers was so loud that even the boats around could hear what sounded almost like a two-strokes engine noise!!! Listen part of the recording gathered today to have an idea of what I meant for MOTO-CACHALOTES 😀 😀 😀




One of the calves of Sperm Whale (Physeter macrocephalus) had a couple of whale louses clinging on its head. Whales came so close we could even spot them with our naked eyes!!! If you wish to learn more about these whale’s ‘inhbitants’ check our post HERE!


After this crazy close encounter we also have the chance to see other dolphin species such as Atlantic Spotted dolphins (Stenella frontalis) and the much larger Bottlenose Dolphins (Tursiops truncatus).


A Bottlenose Dolphins (Tursiops truncatus) interacting with a Sperm Whale (Physeter macrocephalus). Bottlenose Dolphins are quite often associated with other cetacean species but little is known about the aspect of such interactions.


As always in the Ocean, leave your expectations on land, but be ready for the unexpected! 🙂


Lorenzo Fiori

About Lorenzo Fiori

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

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