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The Palinurus genus (frequently transcribed as Panulirus) is represented by numerous species in all of the world’s tropical and sub-tropical seas as well as more temperate waters. It is a predatory, nocturnal animal with a vividly decorated coat. They are often numerous locally; they linger in crevices (with their long antennae sticking out) during the day and hunt small benthic organisms at night, but they also feed on organic detritus whenever they happen across it.

Lobsters have recently suffered a dramatic demographic decline; intensive fishing has annihilated entire populations, especially where tourism abounds. Please record all sightings of lobsters, identifying individual species where possible...

Serranidae

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 economicallymost important fishes of the coral reef, because of their popularity as food. Yetwithout the coral reef there would probably be no groupers. For this reason, groupers are an extremely important indicator species and your record of theirexistence or non-existence during your dive tells us a lot.

The Dusky Grouper (Epinephelus marginatus) feeds on octopi, crustaceans (crabs) and fishes. It lives on rocky bottoms very close to the coasts. Because of its enormous final size (1,5 meters of length) it is the most impressive coastal fish...

Identifying sharks in the wild is a great challenge! While scientists can spend weeks examining every detail of a species, divers may encounter a shark for only a few seconds or minutes. Many species look alike and one individual may not be identical to the next. There are, however, relatively few species in any one specific dive site and with some preparation and a little practice it is possible for all of us to recognise the more common and distinctive species. The key to successful shark identification underwater is a process of elimination, based on a mental checklist of the main features to look for in every animal encountered. One feature alone is rarely enough for a positive identification, so gather as much information as you can before drawing firm conclusions.

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Finned right shoulder along a sloping wall down to 30m. Nice green turtle, chinta nudibranch, jawfish, crocodile fish, banded sea crate, black/yellow flatworm, 2 cuttlefish (male and female (laying eggs). the female can lay up to 400 eggs every 5 mins – phew! This was a brilliant dive and I thoroughly recommend Wakatobi!

Rolled off chase boat tender from MV WAOW onto a coral encrusted shelf by a vertical wall. Gradual slope to a 30m bottom. Nice mantis shrimps, 2 octopi, chrinoids, orangutang crabs (x2), pygmy seahorse on seafan. Big bumphead parrotfish, yellow/green moray, 2 shrimp gobies and a baby lobster. Dolphins on entry but not in water.

Dropped off dhoni onto a submerged reef. Dived left shoulder down a gradula slope to 20m. Really nice Redtooth triggerfish and a big Napoloeon wrasse. Counted 12 groupers over the 60 min dive. Big schools of snappers, oriental sweetlips, 1 whitetip shark and then 2 mantas joined us on our safety stop. Amazing dive!

Dropped down a vertical wall that fell to 60-70m. Wall encrusted with corals and huge gorgonia sea fans (nut no pygmies!), big moray, lion fish and nudbranchs. A big napoleon wrasse cruised out in the blue at about 35m. Big crocodile fish, pink scorpion fish and juvenile lion fish. Tuna and barracuda joined us out in the blue. Wonderful dive!

Dropped onto a a ‘coral bowl’ dive site with a centre sandy bottom. Garden eels in sand with a single anenome in the middle with a harlequin crab. Schools of beautiful and playful batfish (but with parasites on their faces). Crocodile fish, nudibranchs, saddleback anenome with clownfish eating bubbles! Pyjama cardinal fish, spine cheeked anenome fish, floured and spotfin lionfish.

Echinometra and Echinothrix spp

Sea urchins are often used as indicator organisms in public aquariums to determine whether the system is functioning properly. These organisms are extremely sensitive to water conditions and are first to show signs of stress, seen when their spines are laid down or are shed.

Sea urchins (echinoderms) are a group of marine invertebrates that can be found in almost every major marine habitat from the poles to the equator and from the inter-tidal zone to depths of more than 5,000 metres. There are around 800 extant species and the group has a long and detailed fossil record stretching back many millions of years. All echinoderms have tubefeet and these play a very important role in feeding and respiration.

Echinoderms move by means of spines and climb a...

Triggerfishes (Balistidae) are so called because of the triggerlike mechanism controlling the large first dorsalfin spine on the top of their head. Once this spine is locked in an erect position, which the fish does in order to wedge itself into crevices in the coral where it cannot be dislodged by a predator, the spine cannot be pushed down until the short “trigger” spine behind it is depressed. The family name Balistidae is derived from the Latin ballista, another name for the Roman catapult, in allusion to the trigger mechanism of the dorsal-fin spines.

Triggerfish are mostly found on coral reefs, and when under threat they dart into a hole or crevice on the reef, lock their dorsal spine erect and wedge themselves into the reef...