Creature of the Month

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courtesy of Scuba News

Grouper (Epinephelini)

Legend has it that a grouper fell in love with a beautiful
girl but inadvertently swallowed her.  She had with
her shells that she used to cut slits in the grouper and
make her escape.  The grouper thus became the first fish to
have gills.

As well as gills the Epinephelini tribe of groupers have
big mouths and small teeth. They are top-level predators,
mainly found close to coasts. They often appear docile -
hardly seeming to move and resting below overhangs or in
holes in the reef.  When an unwary fish comes within range
though, they rush out and suck the victim into their mouths.

You see groupers all around the world, some species as
far north as Norway.  The biggest type of grouper grows 
to 270 cm and weighs over 300 kg (660 lb or 47 stone).
This is now very rare though.  The potato cod, often seen
in Australia, reaches 200 cm and 110 kg.

Groupers are territorial and solitary apart from during
the mating season in mid-summer.  Then hundreds or even
thousands of groupers gather together at their spawning
grounds.  This behavior has been their downfall in
some areas, as fishermen have drastically decreased their
numbers to unsustainability.  Many governments, however,
are now acting to protect the spawning sites.

Groupers are protogynous: they begin adult life as females
then later change into males.  This strategy is thought
to maximize the number of offspring they can produce.

For photographs of groupers see:

Further Reading:
For a good identification guide to reef fish, including
groupers, we recommend Coral Reef Fishes (Collins Pocket
Guides). Read our review at