If someone asked me what is the most annoying underwater critter to ID after taking a photo of it, hands down has to be Octopus. Other Cephalopods, Fishes and Crabs tend to have defining features which makes ID’ing them relatively straight forward, also because those animals can’t change their appearance without great effort and time, unlike an Octopus which can basically be any colour or shape it wants, whenever it wants!
For instance take this photo above, the Algae Octopus, but you wouldn’t have a clue it was one if it wasn’t creating all those algae like appendages as camouflage. In fact when I first stumbled upon this Octopus it was just popping it’s eyes and a bit of dome out of his den. At first sighting it looked like your common Reef Octopus, he was relatively smooth with dull white and grays, doing his best to blend in with the sand I guess.
I decided to stop and watch him for a bit, simply because we have seen Mimics behave in a similar way, they actually change shape and colour to Mimic the Common Octopus, then all of a sudden they will go full Mimic and do something extraordinary when they know the game is up. So I watched this guy for a minute or two and wouldn’t you know it, he did something extraordinary, grew a bunch of vibrant colourful Algae appendages all over his body.
This was another awesome first actually, it’s possible I’ve seen Algae Octopus before, but never while they were displaying their namesake trademarked behavior of trying to look like a patch of Algae on a rock. The Algae Octopus is named such because it is the only species that can create those super long structures on it’s body (The Algae), those are not permanent features and it creates them for camouflage or mating as necessary.
Other Octopus can create similar structures but no where near to the same extent, length or creativeness of the structures, it’s truly astounding to watch it happen in real life in front of you, the Octopus is literally rebuilding itself in front of you.
Algae Octopus also hunt during the day, much like Mimics, preferring to sleep at night, so it’s awesome to find them relatively active early in the morning when we do our dives, in fact he was probably getting ready for a little crab hunt before I bumped into him.
At first he was quite shy, but after 5 minutes of chilling near his den he became a little more friendly and we were able to approach his home and get a couple quality snaps, looking forward to finding him again soon :)