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
some ancient vestigial behavior? - or, as some speculate, a response
to the submersible's electric field or searchlights?
As of 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. Fish which had been tagged with sonic devices were 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. 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 decade, observations followed in both South African and Indonesian waters. In 2009, a juvenle was discovered, stationed in a cave at 161 meters, in Manado Bay, Indonesia. In 2010, the fish were observed off Biak island in Papua Indonesia.