Transcription of audio taken from a video recorded by Aurelie McTier, 20th June 2022. The main speaker in the video is an unknown tour guide/boat driver.
[Sound of a boat, waves and people chattering. The engine dies down as does the chatter.]
If I can get your attention, please, I think we are in a good spot now. I might be wrong – it happens every so often, less than it used to – but I think there is a very interesting animal on that rock there. Can anyone see it?
[Man’s voice: That rock there?]
Yep, that rock just there. If you can’t see it that’s alright. This animal is very good at hiding itself. Camouflaging. I’ve got some snacks in this box here, maybe we can get it to reveal itself.
[Sounds of a metal box opening.]
[Woman’s voice: Oh my god it’s a fish.]
It is a fish. Not this animal’s favourite food but one that’s easier for me to get. Watch closely and if we’re lucky it will take the bait. [Mumbling] This is going to be really embarrassing if it’s just a rock again.
Alright, one…two…three…
[Screams and shouts. Lots of talking over each other. Snippets can be made out: “What was that, a snake?”; “Almost gave me a heart attack.”; “Oh my god tentacles!”; “Yes! I was right first time!”]
What we just saw was a basking octopus. They’re found all over the islands, but do especially well on the reef where there are lots of rocks and ledges either just below or just sticking out of the water. These octopuses haul themselves onto a rock and then…wait. They can sit on rocks for hours without going back into the water and they do this for three reasons.
Firstly, they store a large volume of water inside their body cavity and use a specialised series of muscles to keep it circulating over their gills drawing out as much oxygen as possible. Secondly, the chemical that carries oxygen in the blood - haemocyanin – is way more efficient than in other octopuses. Thirdly, as their name says they bask. By lying spread out on the rocks and being so dark in colour, they are warmed by the sun meaning they can slow their own metabolism and save energy.
Their dark colour also helps them blend in with the black rocks and like many octopuses they can change the colour and texture of their skin to appear as rock-like as possible. This makes them almost invisible, especially if you’re their favourite food, fast flying seabirds that aren’t paying attention to anything but the water.
Look around at all the colourful birds flying around the reef. They’re marquinhets of different species and the most colourful is the sunset marquinhet. That bird is a skimmer. It flies low and fast over the water’s surface, quickly grabbing fish as it flies by. As it flies it moves up and down over waves and rocks and if it passes over a basking octopus – bam! Those two grabbing tentacles we saw earlier launch up into the air and grab the bird.