19.08.2024 – Deep divers

It’s a strange feeling at the moment, going out to sea, which is a bit gloomy and covered in smoke from the fire. Despite the difficult conditions, our spotter found Sperm whales (Physeter macrocephalus). On the way there, we had a brief contact with Blainville’s beaked whales (Mesoplodon densirostris) who swam across our path. They dared to approach closely. The Sperm whales were active. We saw spy hops, breaches, animals turning sideways and a mother with her calf swimming right under the bow.

Marine mammals known as deep divers are fascinating creatures that have adapted to extreme conditions in the depths of the ocean. We met two of these species today. These animals are capable of diving in deep waters for long periods of time, often at depths of over 1,000 meters, to find their food. What is impressive is their ability to withstand the enormous pressure at these depths. Their bodies are built to withstand the pressure without damage, including through flexible rib cages and special adaptations in the lungs. Deep divers also have large amounts of myoglobin in their muscles, which stores oxygen and allows them to go for long periods without breathing.

One of the young animals breached several times. Whales jump out of the water, a behaviour known as “breach,” for several reasons that have both practical and social functions. A main reason can be communication. The loud impact of the body on the surface of the water creates strong noises that can be heard over long distances and can serve as a signal to other whales, especially in murky waters or at long distances. Another reason is to use breaches to remove parasites from their skin. By jumping and then diving into the water, whales can get rid of unwanted companions such as barnacles or lice. It is also thought that whales breach to show their strength and energy, especially in social situations such as mating or competition with other males. Such jumps may be a form of display behaviour in which whales demonstrate their size and strength. After all, jumps could simply be an expression of play or joy. Whales, especially young ones, often exhibit playful behaviour, and breaching may be part of this. On our morning tour, it appeared to me as if the young whale was jumping playfully.

At midday, the Blainville’s beaked whales were restrained. Beaked whales are a diverse family of toothed whales found in deep oceans around the world.

In the evening, our bottlenose dolphins were very close to the coast. It was a calm, beautiful sighting.

By Fatima Kutzschbach

Sichtungen des Tages

Ribeira Brava

09:30 Blainville’s beaked whales, Sperm whales

13:30 Blainville’s beaked whales

17:00 Bottlenose dolphins

Stenella

09:30 Sperm whales

14:00 Bottlenose dolphins

17:00 Bottlenose dolphins, Striped dolphins