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Cool Fish Behavior

“He who scuba dives all the time will see them fish do the most outrageous and stunning behaviors, so that he will no longer rank the fishes below the animals which walk and crawl on land when it comes to cognitive capacity”

– Pacificklaus

And here are some examples of this very true statement: in this video a blue-spotted puffer fish (Arothron caeruleopunctatus) is pesked by a sharksucker (Echeneis naucrates), a hydrodynamic parasite which attaches itself to other fishes in order to save energy for swimming. The puffer fish jerked and turned to get rid of the sharksucker, but to no avail.
The sharksucker seems to remove crustacean parasites from its host fishes, and this would make the interaction at least partially a mutualistic symbiosis. Given the behavior of the puffer fish, it seems to consider the sharksucker a parasite, though.
Another point is that the sharksucker is not sucking onto a shark – while I shot this footage in a marine protected area, sharks are by now very rare in this part of the Philippines, and the sharksucker has to go with alternative hosts.

Here is the video:

 

Next: a filefish which holds onto the substrate to avoid being swept away by the surge. I filmed this 2 weeks ago in the Philippines. Curiously, I had seen this behavior before, almost a decade ago, on a different continent (Australia), with a different filefish species, but in principle the same trick to stay in place. Enjoy:

And: juvenile snappers which use the spines of venomous sea urchins as a fortress at night. Only one species of snapper does this, and only the juveniles, and only at night:

I hope you enjoyed these episodes of fish behavior,

Best Fishes,

Klaus