[Coral-List] Why do fish swim upside down in caves?

Charles Delbeek cdelbeek at calacademy.org
Wed Feb 3 16:22:26 EST 2016


Our exhibit design consultant asked me this question concerning
Cephalopholis polleni.

My thoughts were that since these fish are bottom oriented they feel more
secure with something on their ventral surface, I also believe they can see
more what is ahead and below them where most predators come from for bottom
oriented fish?? Also when a fish swims into a cave or overhang they are
swimming down a reef face and coming across the opening so it is safer to
remain oriented to the rock face then twisting and turning as they enter to
cave/crevice. Also the shelter holes are in the ceiling so it is easier to
dart into them when it is below them then above their line of sight, but I
am just guessing on these.

Anyone have something more definitive on this?

Thanks in advance!

Best regards,


*J. Charles Delbeek, M.Sc. *Assistant Curator, Steinhart Aquarium
California Academy of Sciences

Desk: 415.379.5303
Fax: 415.379.5304


*cdelbeek at calacademy.org <cdelbeek at calacademy.org> *www.calacademy.org

55 Music Concourse Dr.

Golden Gate Park

San Francisco CA 94118



Discover nature’s secret language in *Color of Life*, a dazzling new
exhibit—now open.


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