06.08.2024 – The best job in the world
August 14, 2024
08.08.2024 – Residents
August 16, 2024
We all need rest. From tiny Madeiran fire crests to gigantic elephants, sleep is essential. As whale watch guides, we can be obsessed with sleep; our teams restfulness is key to harmonious trips with lots of sightings. It’s interesting therefore that many of our guests seem equally fascinated by the topic. Today we were asked about the nocturnal habits of three separate species: Loggerhead Sea Turtles (Caretta caretta), Mediterranean Monk Seals (Monachus monachus), and of course Atlantic Spotted Dolphins (Stenella frontalis).
The truth for all these animals is simple. They don’t sleep like us. The ocean is an ever-changing landscape that always presents a simple daily choice: hunt or be hunted. Thus, although being rested is important to wildlife, they don’t get the chance to fully switch off their brains like us. Both dolphins and monk seals rest half their brains at a time. Seals control this using acetylcholine but will only do it in the water when sleeping in cave beaches. Monk seals will instead sleep like us. Dolphins (never spending anytime on land) will always do the half-brain thing and (especially when they are young) will continue to slowly swim whilst doing so, allowing them to be alert of predators. Fully grown dolphins and large whales have reduced predators and thus often allow themselves to “log” (remain stationary) on the surface of the water. Turtles are completely different; they will rest their whole brains for 4-6 hours a day but will make use of creative sleeping positions to protect their vulnerable soft parts. They may even wedge themselves between corals or rocks to protect.
Well, with that guys, all this talk has got me feeling sleepy myself. I’m off to rest myself for tomorrow’s tours!!
By Peter Worth
Sightings of the Day
Stenella
09:30h Atlantic Spotted Dolphins
14:00h Atlantic Spotted Dolphins
17:00h Atlantic Spotted Dolphins, Monk Seal
Ribeira Brava
09:30h Atlantic Spotted Dolphins
13:30h Atlantic Spotted Dolphins, Loggerhead Turtles
17:00h Striped Dolphins
