ODD BEHAVIOR

 
          When Hans Fricke and his submersible pilot first observed coelacanths at depth in 1987 they saw an odd bit of behavior. From time to time the fishes tilted forward, snouts down, and appeared to stand on their heads. Why? No explanation presented itself. Was this hunting behavior? - or, as some speculate, a response to the submersible's electric field or searchlights?

           Up to 2000, the Fricke submersible visits offered the only direct observations of essentially unstressed coelacanth behavior, save for a brief view by divers off Sodwana, South Africa. Fin movements and swimming styles have been analyzed. Curiously, the coelacanth was never observed to use its paired pectoral and pelvic fins for bottom walking, a behavior that might have been expected of "Old Fourlegs."

          Coelacanths were found to congregate in submarine caves on the steep island drop off during the day, where they hovered without touching each other. Their white scale flecks, set against a cobalt blue body color offer excellent camouflage against the cave surfaces covered with white sponges and oyster shells. A fish which had been tagged with a sonic device was found to leave the caves at the same time late each afternoon to forage along the coastal incline during the night. The drift-feeding coelacanth is an opportunistic predator, scarfing up whatever it can with a suction action of the jaw and hinged cranium.

          Location of prey fish is possibly aided by a rostral organ (in the snout) which acts as an electric field receptor- one explanation for the headstands. The coelacanth's uncanny sense of timing and coastal navigation skills have yet to be explained. Another mystery is the whereabouts of the juvenile fish which are rarely seen in submersible dives and seldom caught by local fishermen.

          Over the decades, observations followed in South African, East African, and Indonesian waters. In 2009, a juvenle was discovered, stationed in a cave at 161 meters, in Manado Bay, Indonesia. In 2010, coelacanths were observed off Biak island in Papua Indonesia.

 


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