Category: Maldives 2023

Update from our Maldives coral reef and whale shark expedition

Here’s an e-mail by our scientist Jean-Luc to Reef Check Italy, who are working with us on a scientific paper. We thought you might like to see this as it contains a nice summary of what we found.

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We visited North and South Ari reefs, last visited in 2018. I was so depressed by the inner reefs then that we moved operations in 2019 and 2022 (post Covid) to South Male’ and Vaavu atoll reefs, that appear healthier.

Conclusions from this year

Outer reefs of Ari haven’t changed much – just accumulated slightly more of the same coral cover since 2018 (Rasdhoo, Bathalaa and Dhigurah wall).

Inner reefs are showing three post-bleaching trajectories:

Trajectory 1

Acropora coral (previously dominant in Maldives reefs over geological time in shallow water environments) recolonise and dominate the shallowest reefs (to 5 m max), where bleaching had damaged them and where grazing is extensive (example site: Kuda falhu). We think (re)growth of any coral below 5 m is difficult in many central atoll reefs, because of extensive rubble fields of unconsolidated material drifting down the slope from previous bleaching, then storm events.

Trajectory 2

A shift to Porites rus (that can be branching and plating and massive in life-form) and Porites cylindrica and Pocillopora (probably P. verrucosa) in (mostly) shallow reefs. These three lifeforms are prevalent in Baros House reef (from a snorkel to the south of the resort), and from surveys in previous years in South Male’ inner reefs – at Beybe’s and Guraidhoo inner (see photos from previous reports of surveys in 2019 and 2022).

Trajectory 3

A phase shift in reefs from coral-dominated to Corallimorph-dominated (worrying). This is the case at Dega thilla. I have recorded in all my time in the Maldives two other reefs entirely dominated by this blanketing lifeform – one was Adhureys Rock way back in 2005. You have the data from that site I think. I think the other one was about 2011 or 2012 (from North Male’ I think – I’ll have to look these up).

So there is little variation in outer reefs, drops-offs, near channel reefs, but the above three trajectories in inner reefs does show this tremendous variation. I suppose there is another where things remain pretty much dead – with low coral cover, and not much else in terms of dominance. That would be expressed by Oshigali finolhu that we visited as our last site (an inner reef near to Dangheti Island, South Ari on the last day).

I hope these observations, and data are useful. As I said in the Wetransfer, we also have photo quadrats at all sites if your students want to analyse these in more detail.

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Other achievements of the expedition include:

Since its inception in 2011, this expedition has thus far trained over 100 people in Reef Check surveying, including over 30 local Maldivians in techniques on how to monitor their reefs and set up community-based monitoring schemes. As a direct result of this, local NGO Reef Check Maldives was formed in 2017 and is now active in community-based reef conservation work and advocacy. Some of these community surveyors are now teaching Reef Check themselves, and are employed by government agencies and private consultancies to undertake management and surveillance. A colouring and educational booklet for local schools has also been produced and distributed around the country with the help of the local Ministry of Education. The expedition has also surveyed reefs that were impacted by the coral bleaching event of 1998, and identified recovery in most reefs prior to the 2016 bleaching event. Data on reefs and whale sharks are given to local and international NGOs, government and other decision-makers, who are planning on increasing the number and area of Maldives marine protected area (MPA)s. Our Reef Check data will form part of that picture when the government considers new MPA areas. Other achievements include: Post-bleaching assessment and scientific paper, assessment of fish populations inside and outside ‘MPAs’, two masters theses with University of York, conference presentations (IMCC, Washington 2009 & ECRS, 2017), four resorts trained in Reef Check, one of which is now undertaking its own Reef Check and hosting coral rehab work, two dive centres (Vaavu atoll, Fulidhu and Baros) trained in Reef Check, award-winning Maldivian expedition placement (Shaha Hashim) now employed by Blue Marine Foundation grouper project at Addhu atoll, national Reef Check Coordinator (Hassan Baybe) at ‘Save the Beach’, Vilingili.

Continue reading “Maldives: Addendum”

Update from our Maldives coral reef and whale shark expedition

We’re done. Another batch of EcoDivers trained, another year of surveys done, another bunch of people looking at reefs with different eyes.

Jean-Luc presented us with some prelim results and thoughts towards the end, the full scientific report will come out in 10 months or so, publications with our now impressive dataset spanning over a decade are in the works.

It’s been a mixed bag of hope and despair, of reality checks, the best and worst of humankind, camaraderie, focus and getting a job done. Thank you to Dune Maldives and the crew of the Theia who looked after us so well allowing us to concentrate on diving for science. Thank you, team, for your efforts and kind words, on record below and on the boat in private. Without you, this expedition would not happen, the data would not be collected and no reports would get written. So stay in touch, come back and we’ll you somewhere, someday on this beautiful, beleaguered planet of ours.

Continue reading “Maldives: Done”

Update from our Maldives coral reef and whale shark expedition

We came here feeling pessimistic. Reefs are battered from all sides – warming oceans, bleaching, acidification, overfishing, exploitation, you name it, we humans inflict it on reefs and the natural world. Indeed some say that this current decade is the last to prevent the total collapse of reefs worldwide.

So we did not expect to find signs of hope, but we have. A dim light at the end of the tunnel, a flicker of hope, however faint. It’s no reason to celebrate, but it shows why citizen science is so important. Without the citizen scientists on this expedition, this message, which we will write up in a scientific report, would not exist or be heard. So thank you to all those on board for enabling this with their efforts and funds.

And here’s the story:

We have found some cause for hope for previously badly affected sites, mainly from the last 2016 mass bleaching event. Sites that are grazed by herbivorous fish and have not been colonised by corallimorphs have partially recovered since 2016. True, the recovery is slow (cue the problems from paragraph 1), but there is some recovery. Baby corals are taking a foothold, surviving on the skeletal corpses of once great boulder corals, finding a space for new life in between dead coral branches, clinging on and growing. But those reefs that have been colonised by corralimorphs are getting worse. They are or have phase shifted from coral to corralimorph reefs, blanketed by nothing but these fleshy creatures, which nothing eats and which take over everything. Once the brown carpet has taken over, nothing is left – no fish, no invertebrates, no corals. This has happened in other parts of the world, for example in Bermuda, where few coral reefs are left.

But we are not there yet in the Maldives and we hope our work makes a small contribution to never getting there.

Continue reading “Maldives: Hope?”

Update from our Maldives coral reef and whale shark expedition

Two days later and we have a boat load full of qualified Reef Check EcoDivers. Congratulations to everyone for passing the written and in-water exams and rising to the challenge.

Even our test survey dive yesterday was good enough to keep the data. Our scientist Jean-Luc was predictably pleased. A small miracle, as he is otherwise quite cantankerous :))

Today started with an early morning lazy dive at a well-known dive spot at Rasdhoo atoll. We saw lots of our indicator fish (grouper, snapper, butterflyfish, sweetlips, parrotfish, etc.), a graceful small school of eagle ray and a handful of sharks cruising a steep reef drop-off going deep down into the blue where us mere mortals with our heavy, noisy and clunky gear to survive in the water cannot go. Jacks cruised the blue too, slow and lazily, like a sheathed arrow, ready to dart at a moment’s notice when prey is near. Above us, unicornfishes amused themselves in our bubbles, below longnose butterflyfish picked away at corals in the reef garden. Resplendent anthias floated between the corals and did their name proud. Parrotfish munched and grated against the corals, their excrement the creator of those white sandy beaches that we associate with the dreamland we call the Maldives. A goatfish barbled its way along the sandy bottom in search of food. A Napoleon wrasse floated by in between us, curious as they are, but, alas, quite small (about our size) as their docile and inquisitive nature is their undoing in the face of the destroyer.

And because we destroy, our job is to research and protect where we can. What was it like 50 years ago, when the Maldives where in a pre-tourism slumber? How many hundreds of snapper would we have seen today, how how many sharks would have policed the blue, how big would that school of eagle rays have been? A whole university perhaps? It’s hard to know and hidden by shifting baselines. We know we are part of the problem and this is why collecting reliable data over many years, in our case over a decade now, is so important. But are we just documenting the inevitable decline? It’s hard to know. The first few days tell us that at least it does not seem to have become worse. But that is only a snapshot impression, an educated guess based on a few observations. That’s another reason why recording things in details is so important and why lazy dives such as this one are rare. Why waste your time being tourists when you can be citizen scientists instead?

So out we are again this morning, checking the reefs we all love.

Continue reading “Maldives: Checking the reefs”