17.11.2023 – Glimpse
November 24, 2023
20.11.2023 – Piloting Wonder in Madeira’s Tempestuous Seas
November 27, 2023
One thing I’ve learnt in my time of working with cetaceans is that they love to chat. Communication is a huge part of their lives, especially amongst the social toothed whales, the larger family that includes the dolphins, the sperm whales, the porpoises and the elusive beaked whales. All need to communicate with conspecifics using bioacoustics in the form of sonar and this sonar (or at least certain frequencies) can be heard using a hydrophone.
Our crew on the Stenella took our newly acquired directional hydrophone on board this morning to see if the Short-finned pilot whales (Globicephala macrorhynchus) and the accompanying pods of Bottlenose dolphins (Tursiops truncatus) had anything to say. Sadly, the animals were more focused on travelling than talking so we were only able to make out a few faint signature whistles.
Directional hydrophones are handy because they help identify the source of the sound, which is particularly useful when tracking down animals or to understand where specific acoustics are coming from within mixed groups, like the one we met this morning. Directional hydrophones are also great for tracking down animals, like the mighty Sperm whales (Physeter macrocephalus), whose clicks from the deep ocean echo up to the surface and allow us to find these deep divers. While we did have Sperm whales this afternoon, we didn’t have the hydrophone on board our traditional boat as we took it down for maintenance.
We hope our efforts to record the animals will be more successful the next times but we aren’t complaining. After all, we had fantastic sightings today which finalised a fantastic week for our team! On top of it all, our team even released a young Cory’s shearwater (Calonectris borealis) today that will hopefully return to its colony here in Madeira one summer to breed and have a chick of its own. The bird was rescued and brought to us by Estefânia, a colleague from a fellow whale-watching company in Calheta, H2O.
By Paula Thake
Sightings of the day
Ribeira Brava
09:30 Bottlenose dolphins, Short-finned pilot whales
13:30 Bottlenose dolphins, Sperm whales
Stenella
09:30 Bottlenose dolphins, Short-finned pilot whales
