Underwater Life: The last thing a glass fish sees

Shards of living glass

Dive any reef or wreck in Colombo and you will see them.


Small shoals of shining glass fish, shining that is when the light hits them. They blink in and out of existence as the light hits them for a kaleidoscopic experience that is sometimes unreal, especially when they congregate in a huge shoal that engulfs you and surrounds you in small shards of sunlight.

Glass fish on a reef

Glass fish and cardinal fish on the Cargo wreck

Usually the glass fish aren’t so spectacular, they hang around in a group of about a dozen close to any sort of crevasse on the reef or ‘caves’ formed on wrecks by the structure of the sunken ship. Presumably they do this for shelter with a place to retreat to if a predator attacks.

What they don’t seem to realize is that their shelter is most often where the attack is launched from. You don’t have to look too closely at the crevacess and cracks to see them. The groupers lie there innocuously, seemingly somnambulant. Blue line groupers are the most commonly seen though flower groupers and a few others are also relatively common, lounging about warily eyeing you as you pass over their heads. Occasionally one will lose its nerve when you come too close and flash into the depths of the reef, showing remarkable acceleration for what seemed like a sleepy fish.

Nonchalant blue line grouper

It is this acceleration that is the glass fishes’ undoing.

The grouper’s tried and tested fishing method is to lie motionless apparently completely ignorant of the flashing glass fish above its head until the small fish, lulled into a sense of complacency drop their guard.

A millisecond later and the shoal is one less.

Still nonchalant...sort of

If you are lucky and patient, you would have seen the grouper metamorphoses from a motionless fish to a blurry missile, mouth gaping as the ambush is sprung. A flurry of activity ensues as the glass fish swirl in confusion and the grouper returns to its post.

Eyeing a target

Peace returns to the reef as the as the glass fish, not blessed with a long memory, forget the ever present danger in the dark.

The last thing a glass fish sees

Kraken’s Gaze

The now familiar outline of the Medhafaru wreck appeared out of the blue-green waters, the bridge tilted at a Pisa like angle with the glass still intact though black with algae. DJ moved off to the front of the wreck as I stayed at the back, my more conservative Suunto demanding that I remained relatively shallow for our second dive of the day.

One of the regular denizens of the wreck, a greenish yellow moray, a species we still have not been able to identify, poked its head out a small structure on the deck. It stared out, clenching its jaws repeatedly, as all morays are prone to doing. This does give these eels quite a vicious look especially with their jagged teeth but apparently all this gulping is just to help circulate water over their gills. It’s still not advisable to go sticking any body parts you are fond of near a moray; in fact that’s a good general rule with pretty much any animal.

Best to stay clear of those teeth

Unfortunately I was experiencing some issues with my camera on this dive with the lens fogging up. Giving up on my efforts to get a pleasing portrait of the eel I turned back to bridge. And that was when I noticed it. It was hard to miss actually. Part of the ship was glowing, first white, and then black, then back to white.  Intrigued by this and slightly concerned that I might be suffering narcosis at the unlikely depth of 15 meters, I decided to investigate.

Cautiously getting closer to the object I noted with some relief that it was an octopus, apparently enjoying a Saturday morning lay down sprawled on the ship with his tentacles spread. On seeing me approach, he decided he had better cut his siesta short and backed out and up in between a staircase running down the ship.

Gimlet stare

Safely ensconced he turned a gimlet eye onto me and glowed red again. Unfortunately with the camera issue and a nosy (Scorpion?) fish getting in the way, I could only get a few shots of his eyes. Eyes which were quite eerie I must say, red with a bright black pupil. Eyes that looked as if the octopus was suffering from a virulent hangover and/or possessed by a demonic influence.

The nosy scorpion fish

Mesmerized by the glare I was getting, I just barely registered movement out of the corner of my eye. As usual on the Medhafaru where fish life is prolific, a group of Jacks streamed past me followed closely by a hunting Giant Trevalley who was so intent on securing its meal that it almost headbutted me in the process.  The octopus took this rather exciting interlude as an opportunity to make a getaway back into the deeps of the ship. As I turned back all I saw was a tentacle retreating into blackness  leaving me to hang by the bridge enjoying the hunting shoals of fish over the wreck until my beeping computer reminded me it was time to return back to the real world.