May22

The social lives of cetaceans

Categories // Bay of Biscay Wildlife Officer

The social lives of cetaceans

Its been a whaley good week on board Brittany Ferries Pont-Aven with 271 sightings! 

This past week the Bay of Biscay really has treated us with many more incredible sightings of our European whale and dolphin species – another 271 individuals have been sighted to be precise! Our crossings to Santander this week have provided us with idyllic whale-spotting conditions - glistening sunshine and no more than a few ripples in the water to set our sea state to near-perfect. These are great conditions for us and our keen wildlife-spotting-passengers to spot the first fin protruding from the water, or the first whale blow appearing on the horizon. On Wednesday’s crossing alone we saw 138 cetaceans comprising of; 24 fin whales, 82 common dolphins, a pod of 9 long-finned pilot whales, six bottlenose dolphins and a sperm whale – you could say it was a whaley good day – pun intended.

Following our presentations this week, many passengers have been surprised about the complex social systems that exist in our whale and dolphin species and have been eager to know more. Unlike many fish species that may produce millions of eggs at any one time, cetaceans will produce one, perhaps two calves, every 1-4 years - so it is crucial that those young survive. Many of the close-knit social systems we see in cetaceans, particularly in killer whales and pilot whales, are matriarchal systems that enhance the survival of those young. Just like we have grandmothers and aunts that help share the load of parenthood, this can be said for our social cetaceans where elder group members will ‘babysit’ whilst mum is diving for food. Group members will also transfer knowledge to each other, such as learning the best locations to find some yummy food!  

One of the most endearing and intricate forms of social behaviour can be seen in our long-finned pilot whales, a species we were treated to as we sailed past the Santander coastline, spotting their black shiny fins and bulbous heads logging at the surface. Despite the advantages of a matriarchal social group mentioned above, they also bring disadvantages. Pilot whales are known for being susceptible to mass standings, this is when the eldest female beaches herself, perhaps if she has become unwell or disorientated, causing the entire pod to also beach themselves. This shows just how strong and close-knit these social bonds can exist amongst our whales and dolphins – this display of altruistic affection is perhaps the reason I first struck a fascination with these enigmatic animals.

Unlike our social cetaceans, fin whales are known for being solitary species – meaning they largely live on their own. However, this week we have been treated to a couple of sightings of a potential fin whale mother and calf feeding and travelling through the bay. This is a crucial time for a fin whale calf, ensuring it gets enough food each day for development and will stay with its mother for around 6-7 months, this along with small groups occasionally migrating together, is perhaps the only time you will see this species with other individuals.

I hope this has wetted your appetite for finding out more about the complex social interactions our whale and dolphin species exhibit. Stay posted for more exciting tales our Bay of Biscay cetaceans have to offer. See you in a week Pont-Aven!

Kirsty

Wildlife Officer Brittany Ferries Pont – Aven