Aug27

HOW DID THEY ADAPT?

Categories // English Channel Wildlife Officer

HOW DID THEY ADAPT?

Just 2 weeks left for Maeva! Find out about some of the amazing unique adaptations of cetaceans in this weeks blog.

Hello again whale lovers!

As we are finishing off our twelfth week on-board DFDS Transmanche ferry between Dieppe and Newhaven, the sunshine is back in all its glory and with it, wonderful news! But first, as promised, let’s learn more about the unique adaptations of whales and dolphins to survive in the marine world.

Living in water implies efficiency and speed in a viscous environment, excellent thermoregulation to deal with cold temperatures and abilities for long dive period in a pressurized place. With no external organs and a highly hydrodynamic body, they are fast swimmers reaching speed of 48km per hour for blue whales when they flee predators. The blowhole, equivalent of a nose, located on the top of the head has drifted from the end of its face (similar to a dogs's) to its current location on the rostrum through evolution as a more proficient solution to minimise the effort while surfacing to breathe. And the second and third cervical vertebrae are fused to keep the head in movement with the body for an adequate swimming shape and position. A thick blubber layer of fat below the skin exists with a limited nerve system to reduce the blood vessel capacity and to serve its true isolation purpose. The right whales have 50 cm of blubber (compared to only 20 to 30 cm for fin and blue whales). So called right whales hints their name as they float when dead, they were the “right” ones to kill. When taking a breath of air at the surface, cetaceans inhale large quantities of air being stored in the lungs, efficiently used at 85% against 20% for human beings and loading their muscles, blood vessels and organs with oxygen. As they are diving deep, the flexible ribcage prevents any potential damages to the lungs. With porous bones filled with blubber cavities, their bone density is really light for optimal movements and to surface with minimum effort. Absolutely mind-blowing right? And I am sure there are even more adaptations that we are probably unaware off today…

This week has been fin-tastic! With perfect weather throughout the week, a sea state at 1 or 2 the entire time, we had more sightings than the last couple of weeks combined! On Wednesday, passengers kept coming to inform me with what they have spotted! Once the presentation completed, we all went on Deck 8 and were rewarded with 3 common dolphins on Port side. Kids were ecstatic, and to be completely honest, so was I. After two weeks locked in, it was the perfect recompense. And it did not stop there… On Friday, I got a video sent from the Cote d’Albatre (at the time I was on the Seven Sisters) of a large pod of common dolphins jumping in front of the ferry. The surprise continued on Saturday with another large pod of dolphins in the distance, quite difficult to identify but most likely common as well, spotted a few minutes before the start of the talk. The majority of passengers on the outside decks 7 & 8 saw them. I hope we get to see more of those wonderful creatures really soon.  

Only two weeks left whale lovers! If you are travelling on the route in this time period, come talk to me before it is too late, I will be delighted to tell you all you want to know about whales and dolphins. In the meantime, have a wonderful week! 

Cheers,

Maeva