06.05.2023 – On the move

We always mention that all cetaceans, as well as other forms of marine life, come here for different reasons. With all the variety that exists in the waters surrounding oceanic islands like Madeira, we find it important to highlight this aspect and its incredible complexity. Why does this species come here? How long does it typically stay and when it leaves, where does it go? These questions aren’t all too easy to answer but consistent transfer of data from our tours and from other whale-watching companies may help provide some insight. 

For now, frequently sighted species such as the Blainville’s beaked whales (Mesoplodon densirostris), a species we encountered aboard our traditional boat at the end of the day, have been prioritised amongst local scientists. Understanding the habitat use of top predators that are sighted all year round is an important tool when it comes to conservation since these important creatures regulate the ecosystems they thrive in. Beaked whales are elusive predators of the deep and Blainville’s belong to the best researched of this group of cetaceans. In Madeira long term research has shown that Blainville females are residents with males moving from one group to another.

Judging by their occurrence, it is understood that Atlantic spotted dolphins (Stenella frontalis) and Short-beaked common dolphins (Delphinus delphis) are seasonal visitors that arrive the warmer and colder season, respectively. Both these small cetaceans arrive in Madeira in large numbers and their abundance makes it hard local scientists to track their exact occurrence through photo-ID. There are, however, indications that some common dolphins here in Madeira may travel to the Azores in the summer but more research is required to confirm these assumptions.

On the other side of the coin, we find species that simply pass through Madeira’s waters using them as a temporary safe haven to rest and feed during their travels. This is true for the enormous Blue whales (Balenoptera m.musculus) that we were lucky to encounter these past few weeks as well as on todays morning tour aboard both boats. These enormous filter feeders are on their way to feeding grounds in polar waters, where the melting sea ice releases phytoplankton into the ocean which serves as a grazing ground for the whales favourite prey, Krill, allowing them to proliferate.

Understanding how cetaceans move through a habitat helps us gain insight on how important it is for them and helps us do our job more responsibly to ensure that these important relationships will not change!

By Paula Thake

Sightings of the day

Ribeira Brava

09:30 Atlantic spotted dolphins, Blue whale, Short-beaked common dolphins

13:30 Atlantic spotted dolphins, Short-beaked common dolphins

Stenella

09:30 Atlantic spotted dolphins, Blue whale, Short-beaked common dolphins

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