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 non-existence 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. The species that we would most like you to record are listed below for the South America – Atlantic Coast subtropical eco-region.
The Lucky Grouper (Epinephelus guttatus), also known as the Red Hind, is the most common member of the Epinephelus species to be found in the region. As with many groupers, it is usually solitary and territorial and is found in shallow reefs and rocky bottoms. The diet consists mainly of crabs and other crustaceans, fish and octopi. This is an excellent fish food which is easily approached by divers, so it is no surprise to find that many of them find themselves impaled on the end of a spear, or dangling on the end of a line! The maximum size is in the region of 76cm with a weight of 25kg. Colouring is greeny-gray to light brown on the back grading to white on the underside, with dull orange-red to brown spots on the head, body and fins. Darker spots on the sides form faint diagonal bars.
The Goliath Grouper (Epinephelus itajara), sometimes called the Jewfish, is classified as critically endangered on the IUCN Red List. Found in shallow, inshore waters to depths of 45m, this indicator prefers areas of rock, coral and mud bottoms. It is also solitary and territorial and feeds on crustaceans. As the largest member of the Sea Bass family in the Atlantic Ocean, 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 Comb Grouper (Mycteroperca acutirostris) is found on prominent rocky bottoms at 3 – 40m. There is limited information on its feeding habits, but it probably feeds on plankton. It can weigh up to 10kg, with a maximum length of 80cm. The Comb grouper is a popular gamefish in southern Brazil for both spearfishermen and rod-and-reel anglers. Here are the other types of Grouper you are likely to encounter in the South America – Atlantic Coast – Tropical eco-region:
- Silky Shark Carcharhinus falciformis
- Smalltail Shark Carcharhinus porosus
- Smooth Hammerhead Sphyrna zygaena
- Spinner Shark Carcharhinus brevipinna
- Thintail thresher shark Alopias vulpinus
- Tiger Shark Galeocerdo cuvier