Blacktip grouper

The blacktip grouper is a small grouper of the tropical Indo-Pacific, named for the dark edge along the spiny part of its back fin. It reaches about 40 cm, is commonly around 22 cm, and can weigh up to 2 kg. It has a wide depth range, from 4 m down to 160 m, and divers most often meet it between 20 and 45 m. Like other groupers it ambushes its food, taking crustaceans and smaller fish.

Also known as: banded rock cod, black-tipped grouper, black-tipped rock-cod, black-tipped rockcod, blacktip grouper, redbanded grouper, stone bass, sea bass, black-tipped rock-cod, black-tipped cod, striped grouper, grouper, red-barred rockcod, redbarred rockcod, blacktip grouper, red-barred cod, weathered rock-cod, scarlet sea bass, reef cod, golden grouper, blacktipped cod, footballer cod, red banded grouper, banded rock cod, seabass, rockcod, black-tipped rockcod, black-tipped grouper, redbanded grouper, blacktip rockcod, red-banded grouper, red banned grouper, dungat grouper, banded reef cod, scarlet rock-cod, rock cod, black tipped cod, blacktip grouper, red-barred rock-cod, blacktipped cod, blacktip rockcod, black-tipped cod, red-barred rockcod, redbanded grouper, scarlet rock-cod, weathered rock-cod, red-barred cod, footballer cod

Many small Indo-Pacific groupers share this changeable body colour, so do not rely on it. The fixed feature is the spiny dorsal fin, already described: a black or dark red outer edge with a pale spot behind each spine. That combination separates it from similar-sized groupers whatever colour the body is showing that day.

The body is a fairly slim grouper shape, the area between the eyes is flat, and the head has a rounded profile above. The tail is moderately rounded. Adult colour varies a lot, from pale greenish-grey through pale reddish-yellow to bright scarlet. There are usually five or six faint dark bars down the flanks, the last one across the narrow part in front of the tail. Each scale on the upper body has a pale centre and a dark rear edge. This gives the fish a faint checked look. The skin between the spines of the back fin is deeply notched, so the fin looks scalloped. The outer edge of that spiny fin is black. A small pale yellow or white spot sits just behind the tip of each spine.

This grouper lives on coral reefs across the Indo-Pacific, from the Red Sea and southern Africa east to the far Pacific islands, and from southern Japan south to Australia. It is common on outer reef slopes below 15 m. It also uses sheltered bays and lagoons in water as shallow as 4 m, and can live in brackish water where fresh and salt water mix. Young fish sometimes shelter in mangroves. It is sometimes seen in groups of ten to fifteen fish.

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  Atlantic goliath grouper

  Epinephelus itajara

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  Barred Hamlet

  Hypoplectrus puella

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  Comber

  Serranus cabrilla

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  Coney

  Cephalopholis fulva

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  Coral hind

  Cephalopholis miniata

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  Darkfin hind

  Cephalopholis urodeta