TYPE THE KEYWORDS “Night Diving Red Sea” into Google, and it will offer some 30 million links. It would take several lifetimes to sift through this pile, but I start looking.
Page 1, 10, 20 – mainly ads for dive centres, prices and courses... then, at last, somebody’s feedback on night dives in the Safaga district, but epithets such as “splendid, fantastic and awesome” don’t tell me much.
There are sites with photos and descriptions of Red Sea inhabitants, but their life-style is mentioned only in passing. There are the YouTube videos, of course, where instead of information we get calming music. But we are contemplating our first Red Sea night dive and need information.
Dive centres may have their own “house specials” involving sharks or turtles or shipwrecks, but let’s create
a set menu of details that can be seen on every typical Red Sea reef.
A reef’s life continues around the clock, and changes from its daylight activities to nocturnal ones don’t happen in a flash. So if you can get into the water just before the sunset, you’ll probably catch sight of some marine creatures preparing for their night’s rest, and others getting ready to hunt.
In the twilight, reef-dwellers seem more numerous than they do in daytime or late into the night. Big moray eels, earlier hiding from the light in their cave-residences, are now swimming along a wall, moving from cover to cover.
Small Samara squirrelfish with sparkling scales and big sullen eyes are emerging from their secluded grottos and coral bushes. Parrots and triggerfish make final circles of their territory to nibble the corals. Schools of anthias, which could be seen by day swirling along the reef walls like a red-orange haze, are now in cracks, as if pulled in by a powerful vacuum cleaner.

THE NEXT SHIFT IS ARRIVING, represented by bright-blue shoals of goldband fusiliers and bluespine unicornfish (these surgeonfish can be identified easily, with two blue horns on both sides of their caudal peduncle).
In daytime these fish may have travelled far in search of plankton. Now they’re back at the reef, looking for a night shelter.
In daylight these unicornfish are watchful, but now they allow divers to approach to within 1m. A shoal appears in the darkening water and moves around a diver in a smooth arc. If you want to watch them changing colour, don’t turn your head in a bid to catch the whole shoal, just concentrate on a compact group of fish and follow them.
A kind of wave suddenly appears to move across an individual’s body, and it takes some seconds to shift from olive-brown to glossy blue, as if a TV control button has been pushed.
Some seconds later, the fish readopts its brown colouration.
The evening shadows deepen, and torches are switched on. This is the time for the reef invertebrates. Danger from fish adapted to search and eat them kept these small creatures in shelters until now, but while their predators are sleeping they have the chance to stretch their feet or fins and find some food.
Invertebrates’ diet usually consists of organic waste accumulated during the day, so the reef is usually much cleaner when the morning comes.
Leathery or soft corals appear in our streams of light. Their yellowish caps, smooth during the day, are now covered with an enormous number of long, semi-transparent villi, fringed at the ends – the anthozoans have started work.
Lots of corals actively filter sea water at night, and this can be seen when looking at the white pulsating soft coral Heteroxenia.
Its large polyps are decorated with corolla, each with eight featherlike tentacles. These rhythmically contract one by one about 40 times per minute, extracting small particles of organic matter from the water flow.
Black balls are moving their long sharp needles across coral blocks or the sand between them – these are long-spined and hatpin sea urchins.
Biologists can distinguish between them, but the problems they can cause inattentive swimmers with the thin needle-like spines that can pierce a diver’s fins are identical.

LONG-SPINED SEA URCHINS have spines that can extend to 30cm and more, and they shift quite slowly.
Hatpin urchins’ spines are shorter (15-20cm) so they can “run” much faster, at about 1.5m per minute. And they do run - between their spines there are five rows of thin, flexible feet with suckers at the end.
There can be thousands of these feet, controlled using a special hydraulic system. The urchins can not only crawl along a smooth seabed but can conquer vertical cliffs.
The one we should really fear is the sea fire urchin. The name comes from its bright red colouring. Each of its spines carries a small pearl, so when it moves the spines a nacreous wave effect is the result, looking delightful against its scarlet body.
Beauty is deceptive, however. Each pearl is a bubble containing virulent paralytic poison. Physical contact will result in a terrible burn.
The slate pencil sea urchin is harmless compared with its relatives. It moves along the bottom slowly on its blunt purple needle-stilts. But it is unmatched at gaining access to a small crack in a hurry.
Sea gherkins or holothurians, which are other examples of echinoderms, can be seen during the night on sandy clearings between reefs. The sea cucumber has a pimply body of different green hues, not unlike its vegetable counterpart except in size, typically 40cm.
Godefroy’s sea cucumber doesn’t look like a vegetable, more like a semi-transparent worm some 50cm in length. At night it emerges from the sand to explore the bottom, searching for organic food with tentacles located around its mouth.
Sea lilies filter the water column for the same purpose. These animals, looking like flowers crossed with fans and measuring 30-40cm, explode their petal-feathers on the top of coral blocks. But unlike flowers they don’t stay rooted to the spot.
If you point your torch at this creature, it will probably assume that it’s morning, close its flower and leave with unhurried movements in search of somewhere to hide. Sea lilies can even swim and glide in an emergency.

IF YOU SEE WHAT LOOKS LIKE an expanded fern bush on top of a rock, don’t be surprised. And when the fern’s leaves start rolling up to form a tangled goblet shape, don’t worry.
This is another echinoderm, the basket starfish. It resembles its close relative Gorgonocephalus – the Ancient Greeks compared this organism with the head of the mythical monster that had wriggling snakes for hair.
At night-dive briefings guides often mention crayfish, but more times than not they remain unseen. Large crustaceans are not that common a Red Sea reef sight, though it’s quite possible to meet variable coral crabs, one of the crested hermit crabs.
If you’re observant, however, you will find lots of brightly coloured small crabs and shrimps, disguised according to the colour of a corresponding coral, sea lily, sea urchin or even the body of a Spanish dancers.
The Spanish dancer is a huge (40 or even 50cm) bright red sea slug. In an emergency it can swim rapidly by twisting the sides of its pallium, hence the name, so divers often startle the mollusc just to watch its miraculous flying dance. Judging by the abundance of dancing Hexabranchus sanguineus online, it’s clear that many people have not let their conscience get in the way!
A pleasant surprise when night diving is a meeting with a cephalopod. Small octopuses are common in shallow water, although they are extremely unsociable.
If there is at least a small crack nearby, an octopus can draw itself into it with startling agility. It might look as if not even a tentacle would fit, but in seconds the shape-shifting octopus can flow into the tiniest slot.
Squid are less fearful. If you meet the bigfin reef squid, follow it without causing any disturbance and you’ll be able to watch colours playing across the body of this 30cm cephalopod for quite a while.
What about fish Swim along reef walls and under almost every protuberance and in each small hole you’ll see fish from the daytime menu getting some sleep in.
There are butterfly and angelfish, various types of surgeon and boxfish, and when a beam of light catches them, they hurry to a darker place.
Goldband fusiliers, trumpetfish, different types of orbicular burrfish and white-spotted puffers are familiar dwellers of coral gardens or sandy clearings.
White-spotted pufferfish usually park themselves on the bottom next to a stone or a small coral bush, and the more common masked puffer in particular remains very sensitive even when it sleeps. Touched by light, it will fly into the water column, quivering its fins as if impersonating a helicopter.
The sweetest dreamers are parrotfish. They not only get deeply into a crack or under a stone but also create a cocoon of protective mucus around their body. This is not secreted from the skin but spat from the mouth. Scientists believe that this protects them from parasites and helps to maintain an electrolyte balance in the fish’s body.
For some fish, however, night-time is their most active period.
The giant moray continues the hunting raids started in the twilight. The tentacled flathead or crocodilefish seeks out good places where it will be able to remain in wait for prey next day.

IF YOUR NIGHT TRAIL above a sandy clearing is crossed by a red lionfish, follow it, illuminating the sand ahead of it. When a small, semi-transparent cardinalfish gets into the beam of light in search of planktonic crustaceans, the lionfish spreads its sail-fins wide apart and, moving a bit faster, homes in on its prey. The cardinalfish dashes aside but the lionfish follows, and this may be repeated.
Soon, tired or lulled by the lionfish’s slow movements, the cardinal freezes. The lionfish behaves like a hunting dog – head down, it hovers above the doomed fish and edges closer millimetre by millimetre.
A dramatic final rush and a cloud of sediment shoots up – the red lionfish gulps in strained fashion and starts looking for more prey.
Within half an hour of successful hunting the lionfish’s belly looks stuffed. Often two or three will hunt together, combing a sandy clearing fin to fin. Their prey’s chances of survival are slight.
The list of Red Sea night creatures may be added to depending on depth, location or distance from reef to shore, but our goal was to create a standard night menu. You’ll see most of these species wherever you dive.
In the interests of safety, dive centres prefer to conduct night dives on a shore reef protected from strong currents, and the chance of sharks or other big predators putting in an appearance is minimal. Concentrate on not getting caught by urchins or burnt by fire coral – panoramic sweeps of your torch and good buoyancy control should be enough.
Take a back-up as well as a main torch, though it’s actually quite difficult to get lost while night-diving, even without a torch. Lights emanating from a well-illuminated dive-boat can be seen over some 100m of water, so it’s easy to detect the “home” destination most of the time you’re diving.
And take your stills or video camera – as we’ve found, there can never be enough night-dive YouTube movies or photo galleries on the Internet!