Is a reef condemned to be a wasteland once the corals are dead?
Not necessarily. When corals grow to form a reef, they create a three-dimensional habitat in a desert of blue. With the vast variety of shapes and sizes corals come in, each type of coral provides a unique range of habitats for marine life. A goby makes its nest in the sand, just at the base of a coral where there’s a small hole. Humbug damsels are so tiny they can flit in and out of the branches of an staghorn coral. The all-too-well-known clown anemonefish peers from an anemone, the curtain of tentacles sweeping past their faces as they watch me cautiously. Not all of these animals disappear when corals die. Yes, when live coral in an entire reef dies it is a tragic sight. It’s eerily way more quiet than the live reef that bustles with the clicks of snapping shrimp and the munching parrotfish. Filamentous algae creeps over the dead coral, like cobwebs in an abandoned storeroom. At first glance, it does look like a wasteland. Many of these animals, especially those that are SUPER dependent on corals are likely to go locally extinct. You can read more about what happened because of the 2016 bleaching event last year in Maldives here, and they type of marine life that is heavily reliant on corals.
One particular fish that has completely disappeared from many of the reefs is the Citron goby (Gobiodon citrinus), which resides in branching corals like Acropora. Danielle, our head of the marine lab here, told me sadly that they haven’t seen any of them since the bleaching event last year. She thinks it’s likely that they went locally extinct.
The brightly coloured citron goby that has been wiped out in many of the reefs in Maldives, resting on an Acropora or staghorn coral (Image source).
Today I dived in two locations the first was Mas Giri, the second, Barros reef. Almost all of the hard corals at the Barros reef were killed off, and a large portion of the corals at Mas Giri was dead too. It was a tragic sight to see the corals as rubble, covered with the fine hairs of algae. That said, it was remarkable to see how much life remained. To the untrained eye, divers who can’t tell the difference between rock, live coral and dead coral probably wouldn’t even be able to tell!
A mushroom coral (Fungia sp.). Luminescent corals are sometimes a signal that they are about to bleach, simultaneously sad and beautiful.
The reef at Mas Giri was scattered with soft corals and tonnes of red-toothed triggerfish just going around and nibbling at algae. As I approached, they’d dart straight into the crevices of rock and coral rubble, just their long tails sticking out oddly.
The red-toothed triggerfish (Odonus niger) literally filling up the entire reef. They must have been around in the thousands. All triggerfish swim with their dorsal and anal fins, undulating them instead of their tail fins like most other fish.
Another rather common triggerfish we spotted was the boomerang triggerfish (Sufflamen bursa). You can see it with its dorsal spine raised up high, and it probably didn’t like that I was taking a picture of it so I stayed at a distance. Triggerfish have a retractable spine at the top of their heads that they use for defense or to lodge themselves in rocks when they sleep.
Apart from the triggerfish, there were a lot more different types of fish as well! I guess it just goes to show that despite a lot of the coral dying from last year’s bleaching event, there is still a significant amount of biodiversity within the vicinity. All hope is not lost!! Come, let me bore you with more fish ID and facts about sea creatures now. It’s actually good practice for me because I’ll have to learn how to identify them to species level soon and it’s definitely a daunting task with so many different kinds of fish! As always, if you think I identified some animals wrongly do let me know so I can learn!
Spotfin lionfish (Pterois antennata) These are venomous fish and ambush predators, they have very few natural predators.
One of the most common residents of the reef here are the pinstriped butterflyfish (Chaetodon lunulatus). They usually occur in pairs, and feed exclusively on live corals. Coral loss due to bleaching can be a problem for them, but luckily they eat a variety of corals, so they’re still able to survive.
The long-nose butterflyfish (Forcipiger flavissimus)…remember this guy from Finding Nemo? That’s Tad, one of Mr. Ray’s students who dared Nemo to touch the boat!
Pin cushion sea star (Culcita schmideliana) These blobby looking guys are a bit problematic because they unfortunately feed on corals here and can cause a lot of damage in large numbers!
This is a feather star or crinoid, a strange looking animal related to sea stars. The long tentacle-like parts are actually its feeding arms. Each arm is covered with hundreds of tube feet that traps small particles of food drifting in the sea. Then, it rolls in slowly into the center of the body where the mouth is.
Saddled pufferfish (Canthigaster valentini), a poisonous fish that other non-poisonous fish (such as the Mimic filefish) very convincingly try to look like.
Don’t they look the same!? Guess which is which! You can tell them apart by looking at its fins…the file fish has generally longer dorsal and anal fins (left) compared to the puffer (right). More scientifically, the puffer has a single dorsal spine while filefish has two dorsal spines (Image source)
Phantom bannerfish (Heniochus pleurotaenia)
A huge school of blue-striped snapper (Lutjanus kasmira), probably finding shelter in the reefs from strong currents.
I spotted this elegant sea star (Fromia nodosa) hiding under a rock, these sea stars are nocturnal, coming out to feed on molluscs, corals and microalgae at night.
Anemonefish with a bubble-tip anemone
Soldierfish and squirrelfish
A cushion sea star…or as I like to call it…the Patrick sea star (Choriaster granulatus)! Looks pink and squishy and derpy just like Patrick from Spongebob Squarepants. Unlike Patrick, it doesn’t eat crabby patties but just feeds on algae and detritus.
An insanely well camouflaged scorpionfish (Scorpaenidae) that I almost overlooked. Was looking around for nudibranchs when this guy was in front of my face. I’m honestly quite pleased with myself for spotting that because I usually tend to miss out these guys. They’re also venomous, so good thing I didn’t stick my face too close to it too.
This beautiful flowerpot coral (Goniopora sp.) had some of the polyps retracted into the skeleton. These corals are entrancing to look at, their polyps opening and closing like millions of small hands reaching out for food! Also, this is quite a disgusting image, but when the polyps emerge, it kind of looks like blackheads being squeezed out. Not for those with trypophobia for sure!
This warty looking thing is a nudibranch (Phyllidia sp.), or a sea slug. I absolutely love looking out for them when I’m diving because they’re so brightly coloured and beautiful to look at. Their colours act as a warning to predators not to eat them because they’re supposed to taste very nasty (no, I haven’t tried eating them). Also, I love that they’re incredibly slow moving and will stay still for you to take a good photo…so that’s always an added bonus!
So that’s it for my first fun dive in the Maldives. I’m especially happy because the boat crew offered me some fruit (god I could kill for some durian sago now), and we saw a pod of more than a hundred dolphins in the distance! My face is at least 6 shades darker than my belly now, but I’m obviously just over the moon.
The feeling here after diving is bittersweet…So much of the reef has been damaged by the extreme weather last year, with the El Nino, but despite all this carnage life still carries on. The coral skeletons here still host a vast array of marine life and the reef WILL recover!