15.06.2018 – Communication is key

Communication is incredibly important for us here at Lobosonda, both within the team and with our clients. Our primary goal is to provide our guests with both an inspirational and an educational experience. The encounter with the animals is accompanied by some information on the threats cetaceans face as well as some facts about their biology and their social lives. The fact that cetaceans have social lives means that even they must communicate with each other and they do so using various vocal techniques.

Today most of our encounters were with dolphins, which belong to the toothed whale family, the Odontocetes. Unlike baleen whales, odontocetes lack vocal chords and use an organ that is specially designed for bioacoustics or biosonar.  In the case of delphinids and beaked whales this organ is compact, oval-shaped and referred to as the melon. The sound waves generated in the melon are used for communication, hunting and echolocation, giving the animals several important advantages in their vast underwater habitat. Sound waves travel five times faster in water than they do in air and vision can be extremely limited in underwater habitats, especially at depths beyond 50m and under turbid conditions, making this system fundamentally important and extremely efficient for cetaceans. Generally sound waves are generated by  the phonic lips near the melon, reflected by the the skull and then modulated in the melon, which acts a an acoustic lens. The melon is composed of several kinds of lipids with different densities allowing the animal to modify and focus sound waves according to its needs.

Dolphins emit a series of high frequency clicks amongst one another which can be categorized into clicks, whistles and burst pulses. Clicks are used for both echolocation and communication and are referred to as burst pulses when they occur in series with 600 repetitions per second. Dolphins also communicate using so-called “signature whistles”, where each individual produces its own characteristic whistle, allowing other members of the herd to recognize it. These whistles can often be heard on board during our tours, particularly when the animals swim in a compact group at our bow.

On both tours we encountered Atlantic spotted dolphins (Stenella frontalis), Bottlenose dolphins (Tursiops truncatus), Short-beaked common dolphins (Delphinus delphis) and, additionally, also managed to briefly spot some female Blainville’s beaked whales (Mesoplodon densirostris) during the afternoon trip. In contrast to dolphins, beaked whales generally spend most of their time at deeper depths where they hunt and socialize. They are therefore more sensitive to the noise generated by boat traffic and are more timid during whale-watching encounters.

By Paula Thake

Sightings of the day

Ribeira Brava

09:00 Atlantic spotted dolphins, Bottlenose dolphins, Short-beaked common dolphins

13:30 Atlantic spotted dolphins, Blainville’s beaked whales, Bottlenose dolphins Short-beaked common dolphins