It was a quiet morning at Octopolis, down in Jervis Bay, Australia. Not much going on, a few octopuses at home… and then:
It’s a Wobbegong, or Carpet Shark (probably Orectolobus halei). They lie inconspicuously on the sea floor – or, at least, as inconspicuously as a 6 foot long shark can lie – and ambush passing prey. This one exploded upwards like a fleshy, toothy firework.
Below is a shot of his face (a crop – probably not smart to get this close).
The only comments I’ve seen about the “beard” suggest it helps with camouflage, as it makes it hard to see where the head ends and sea floor begins. Here’s the video of the whole sequence above, including a slow-motion version at 1/4 speed.
Octopolis is a site I study with Matt Lawrence and David Scheel. (The video, including the screenshots above, was taken by a GoPro camera left at the site.) Two large Wobbegongs seem to have moved in, and this is not good news for the octopuses. Numbers are down, and the octopuses that remain are being very cautious indeed. The sharks, rays, and other fish at the site are starting to form a story of their own, though. The photo below is interesting. In the background there is a Wobbegong, in the very front there is a baby shark of another species – a Port Jackson shark – and if you look closely, between them there is a tiny octopus.
(If you can’t see the octopus, click here.)
Here’s a portrait of him or her, sitting very quietly, just about the smallest octopus I’ve ever seen.
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Notes
‘Destination NSW’ asked me to put in a link to their information page for visitors to Jervis, which I am happy to do. It’s a very good place to visit. The information page is here.
How often have you been monitoring this group? Could we be seeing the natural die off of the observed group and the little guy a hatchling that is now large enough to observe (my guess would be somewhere around 5 months old if they are similar to the ones I have kept)? The presence of the sharks may have to do with opportunistic feeding on dead or dieing animals but it seem that you would have seen indications on film.
Matt Lawrence found the site in 2009, and I’ve been involved since 2010. That’s long enough for several generations. Matt has seen sequences in the past where the site has been beaten up, the numbers drop way down, and then they slowly recover. The wobbegongs seem to be new, though. We saw one there last year, but these guys have now been around for a while. We’re preparing a paper on the ecology of the site at the moment.