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Pufferfish Jackfish Commensalism II

On a recent night dive in the Philippines I saw this unusual pairing of two fishes. A juvenile jackfish, Carnagoides armatus, was hanging out next to a pufferfish, Arothron manilensis. Here is a photo of the pairing:

Pufferfish Jackfish Commensalism II

A few months ago I had seen a very similar pairing, but that time the puffer fish was the closely related Arothron immaculatus. It seems that the jackfish is using the puffer as a hunting cover, or as a cover against predators, it would not move from its side. Back then I had gotten some video of the encounter:

To me it’s amazing how many clever decisions fishes take. The jack is clearly gaining an advantage from the pufferfish, and it sticks with one puffer fish partner for at least several days in a row, as evident by the pairing at night. As so often this kind of behavior is very specific, with one jack species, and only the juvenile, pairing with individuals of two species of pufferfish.

Best Fishes,

Klaus