Be sure to read our monthly updates from Marine Savers – direct from our resident teams at
the Marine Discovery Centres at Landaa & Kuda Huraa – our long-term partnership with Four Seasons Resorts Maldives.
Landaa Giraavaru
At Landaa this month, we transplanted 25 new coral frames, kindly sponsored by guests (7), the Resort (17), and online (1), adding ~1000+ new coral fragments to the reef. Frames were planted at our “Plankton” site (to be seen by divers) and around the Water Villas (for guest interest). We also monitored (cleaned, repaired, photographed) ~160 coral frames, mainly at our Bissie’s Reef site.
To see the progress of your own frame, please visit our dedicated Four Seasons monitoring page where we upload new photos every 6 months or so.
Coral Predators
To date, over 1,000 Drupella snails have been removed from the House Reef and Water Villas, and they are now becoming increasingly difficult to find – an encouraging sign that ongoing maintenance efforts are working. The most frequently observed species, Drupella cornus, is also regarded as the most destructive of the genus, known for rapidly consuming live coral tissue and often nesting in large aggregations.
Thanks to our intern Libbie, we have developed a shell-cleaning and recycling system to ensure nothing from the removal process goes to waste. Collected shells are naturally cleaned using ants before being redistributed, some to nearby vegetation for land crabs, others returned to the sea for marine hermit crabs. And thanks to our intern Molly, selected shells are also being prepared as coral spawning settlement tiles, potentially offering a sustainable and cost-effective alternative to ceramic plugs.
Sea Wall Corals
The coral recruits on the sea wall are continuing to thrive, showing healthy growth and vibrant coloration. We observed this month that a large proportion of the corals on the sea wall are approximately the same size, indicating that the recruitment of these corals most likely came from a single event. It’s encouraging to see these young corals adapting well to their environment – a positive sign that our restoration efforts are helping to create suitable habitats even in modified reef areas.
Water Villas – Recycling Project
Our Reefscapers intern Libbie has continued to lead the Water Villas Coral Frame Recycling and Re-fragmentation Project, maintaining steady progress across the site despite periods of poor weather. Villas 301–309 are now fully completed, with 108 frames re-fragmented and 80 degraded frames recycled. Of these, 42 frames have been transported to the Staff Jetty for collection and recoating, while 38 remain stacked underwater awaiting transport. Work has also advanced between Villas 401–409, where 18 frames have already been cleared and stacked, with an estimated 100 further frames to be prepared in the coming weeks. Viable coral fragments from degraded frames continue to be carefully relocated to healthier structures for re-fragmentation, ensuring minimal coral loss and maximizing restoration success.
As Libbie’s placement at Landaa Giraavaru comes to an end, she is preparing a detailed handover guide for our Reefscapers coral biology team to ensure smooth project continuity. The remaining restoration work at the Water Villas will be passed on to the next incoming JCU Master of Marine Biology intern, who will continue frame recycling and monitoring in collaboration with the Reefscapers team. Libbie’s efforts over the past months have greatly contributed to the long-term restoration goals of the site, strengthening both coral health and operational efficiency across the program.
Coral Spawning – October Full Moon
This month, we expanded our team to 7 divers, with everyone eager to witness coral spawning for themselves! Both freedivers and scuba divers covered different parts of the reef and were able to capture as much spawning activity as possible. During these night dives, we were thrilled to witness several coral genera releasing their gametes into the water column, including: Acropora, Galaxea, Goniastrea, Astraea.
Gamete Checks for November Spawning
In preparation for next month, our team has been heading out to the reef to check which colonies and species are gravid (ready to spawn). This involves freediving down to selected colonies, carefully taking a small branch from near the centre, and examining it for the presence of oocytes (developing eggs). These early checks help us understand which species are readying to spawn and allow us to plan our monitoring dives accordingly.
When gametogenesis first starts, the eggs are white; as the time gets closer to spawning, the eggs mature and become pale pink, slowly turning dark pink/red just before spawning!
Spawning Device (staff beach)
During October, we have been busy restoring and refining our coral spawning device in preparation for the upcoming spawning events. The device is designed with a square base and conical sides that slope inward toward the centre, guiding gametes to float up through a central tube. Inside, the gametes fertilise and develop for around 3-5 days before drifting back down into the surrounding reef environment, where they can naturally settle and grow.
In previous years, the conical shape of the structure was maintained using floating buoys. This season, we’ve improved the design by constructing a rectangular frame with the middle section sitting about one metre higher than the corners. This modification creates a more stable and efficient setup, helping the device capture and retain gametes more effectively while withstanding currents and wave action.
Alongside the structural improvements, we carried out essential maintenance and site preparation. Two damaged concrete anchor blocks were replaced to secure the device firmly in position. We also removed old, dead frames and non-viable coral colonies, making space for new growth. Finally, gravid (egg-bearing) colonies were carefully attached beneath the tent structure, ready to release their gametes and kick-start the next generation of coral life on the reef.
November Spawning Plan Settlement Preparation
During the November spawning events, we hope to collect Acropora tenuis gametes for rearing ex-situ in our Fish Lab tanks to monitor settlement and early development. A range of settlement substrates have been collected, including ceramic tiles, coral plugs, and (experimentally) Drupella shells (which offer a calcium carbonate surface that mimics the natural reef environment to encourage larval attachment).
Within the tanks, environmental conditions such as light intensity, temperature, and salinity will be carefully monitored and adjusted to maintain optimal conditions for coral larval settlement. These controlled setups allow us to better understand the preferred settlement cues of A. tenuis and improve future restoration and larval propagation efforts.
A collection of resident herbivores will help to reduce the spread of biofilm and algae within the tanks. We have identified a few herbivores that could be useful, including : bubble snails (Bulla vernicosa), sea hares (Dolabella auricularia), urchins (Echinometra mathaei), and Trochus (Trochus maculatus).
Kuda Huraa
At Kuda Huraa this month, our coral experts transplanted 6 new frames, kindly sponsored by guests (4), the Resort (0), online (0), and recycled (2). In addition, we monitored and repopulated 55 growing coral frames, and monitored a total of 61 frames.
To see the progress of your frame, please visit our dedicated Four Seasons monitoring page where we upload new photos every 6 months or so.
Reef Maintenance
This month, we performed maintenance tasks across all four restoration sites around Kuda Huraa. Some rough weather prevented access to the House Reef for our maintenance and monitoring tasks, as well as scheduled spawn-monitoring dives. When conditions allowed, we deployed our temperature loggers on the reef, and performed gravid checks. Additionally, two frames were recycled during two Junior Marine Savers activities.
The Channel Repopulation
The fragments of Porites cylindrica at our Channel site continue to be threatened by algal overgrowth and sediment movement. Many fragments from recent repopulation efforts have died or remain unattached to the frame. This month, huge effort has been taken to improve the overall appearance of the channel restoration site. All active guest frames have been monitored, and many previously buried frames have been lifted out of the sediment and relocated. For frames that proved difficult to remove, we repopulated these with large Porites cylindrica colonies or Montipora digitata fragments. We hope that the fast growth rate of Montipora digitata will quickly improve the appearance of these frames.
The Channel Species-specific Experimental Frames
Since Porites cylindrica is not thriving at our Channel site, we initiated trials with alternative species to see which would be more suitable for frame repopulation. We repopulated four experimental frames with three species: Pocillopora verrucosa, Pocillopora damicornis, Montipora foliosa.
P.verrucosa – has demonstrated high resistance to bleaching, and several large, thriving colonies exist on our Channel coral frames. Across the Vaboh Huraa reef break, there are also many wild P. verrucosa colonies. We used fragments from both the resident channel colonies and Vaboh Huraa reef break colonies to build two experimental frames in the Channel. Surprisingly, only the Vaboh Huraa fragments have survived, while the channel-site fragments died. These surviving fragments are, however, exhibiting heavy algal overgrowth, so we will monitor that frame closely.
P.damicornis – At the channel site, there are several wild colonies of this species, as well as a few thriving colonies on our coral frames. Therefore, we created an experimental frame using fragments from these existing mature colonies. Unfortunately, these fragments did not fare well, bleaching quickly after placement and subsequently dying.
Montipora foliosa – an incredibly fast growing and beautiful species. Although not naturally occurring in the channel restoration site, it would be an incredible addition. So far, the experimental M.foliosa frame has shown no signs of bleaching. We will monitor this frame closely and hope that the fragments attach in the coming months.
Coral Predators
This month, our team conducted an increased number of cull dives targeting corallivorous organisms across our restoration sites. At the Water Villas, a total of 746 Drupella spp. were collected this month, marking a significant rise compared to September. Among other coral predators at this location, Coralliophila erosa was the most abundant species, with 25 individuals recorded, followed by Drupella cornus and Coralliophila costularis. During the night dives for coral spawning and morning maintenance dives at the House Reef, three cushion starfish (Culcita schmideliana) of small to medium sizes were removed.
Coral Reproduction Programme
This October’s full moon marked the beginning of the second annual spawning window. We carried out gamete checks on several species of Acropora prior to the full moon, but only found white immature oocytes. Due to poor weather in the early evenings, we were unable to perform all our scheduled night dives on the House Reef, and no spawning was observed.
Subsequently, we have located pigmented oocytes in multiple Acropora colonies, along with further white and pale-pigmented oocytes. We are hopeful that the November spawning window will allow us to continue our observations, witness spawning in action, and collect data from any spawning colonies.
Photos below – coral eggs at different stages of maturity (pigmentation increases before spawning).
