When people talk about coral reefs, fishermen tend to shrug their shoulders and complain about snagged lines and torn nets. But when you talk about groupers, they suddenly sit up and pay attention. Groupers are among the economically most important fishes of the coral reef, because of their popularity as food. Yet without the coral reef there would probably be no groupers.
For this reason, groupers are an extremely important indicator species and your record of their existence or nonexistence during your dive tells us a lot. Like all indicators, it is valuable if you can record the particular species you sight. However, recording the total number of groupers is just as important. Some of the species that you may encounter in the warmer waters of Chile and north to Central America are listed below.
The goliath grouper (Epinephelus itajara), sometimes called the jewfish is classified as critically endangered on the IUCN Red List. It is present in the eastern Pacific Ocean from the Gulf of California to Peru, although unlikely to be seen as far south as even Chile’s warmest waters. Found in inshore waters to depths of 45m, this indicator prefers areas of rock, coral, and mud bottoms. It is solitary and territorial by nature and feeds on crustaceans. It can reach lengths of 2.5m, and weigh up to 450kg. There is anecdotal evidence of goliaths stalking and attempting to eat divers!
The jewfish is notable as one of the few groupers to be seen in brackish waters. It is territorial near areas of refuge such as caves, wrecks, and ledges, showing an open mouth and quivering body to intruders. It can also produce a distinctly audible rumbling sound generated by the muscular contraction of the swim bladder. This sound is intended both as a warning to intruders and as a location method for other groupers. Here are the other types of Grouper you are likely to encounter in the South America – Pacific Coast – subtropical eco-region:
- Broomtail Grouper Mycteroperca xenarcha
- Gulf Grouper (Vulnerable – IUCN) Mycteroperca jordani
- Itajara (Critically endangered – IUCN) Epinephelus itajara (aka Goliath or Jewfish)
- Leopard Grouper (Vulnerable – IUCN) Mycteroperca rosacea
- Sailfin Grouper (Vulnerable – IUCN) Mycteroperca olfax
- Sawtail Grouper (Vulnerable – IUCN) Mycteroperca prionura
- Spotted Grouper Epinephelus analogus
- Starry Grouper Epinephelus labriformis