Reefscapers at Sheraton Maldives [SM 2024.02] dolphins

Sheraton Full Moon

During March, we built 17 new coral frames, and out-planted at depths of at least 10m to help protect against warming temperatures. A total of 92 coral frames were monitored at various sites around the island.

To see the progress of your frame, please visit our dedicated Sheraton monitoring page where we upload new photos every 6 months or so.

Reefscapers at Sheraton Maldives [SM 2024.02] coral frame growth SH520

Our coral frame SH520, showing 6 month’s growth from October 2023 to the latest monitoring photo (2 April 2024).

Coral Spawning & Gametogenesis

While recycling and collecting fragments for frames, we did not spot any gametes in any species. We conducted spawning monitoring around the full moon period, but no spawning was observed in any species. We are anticipating a large spawning event in April.

Reefscapers at Sheraton Maldives [SM 2024.02] coral frames ray

A blotched fantail ray (Taeniurops meyeni), keeps us company during our coral maintenance work

Coral Bleaching Monitoring

We began our bleaching monitoring in early March, following the Maldives (MMRI) Protocol, adapted for Reefscapers goals. Therefore, we are swimming line transects of coral frames and recording the bleaching level based on the MMRI scoring system for bleaching, while taking monitoring photos of each frame for potential use by our bespoke in-house AI software.

Bleaching score key: (1) No bleaching, (2) 1-10% of colony bleaching, (3) 11-50% bleaching, (4) 51-99% bleaching, (5) 100% bleached, (6) Dead.

Three sites were chosen for bleaching monitoring:
– Water Villas – 6 transects (3 frames/transect = 18 frames);
– Blue Hole – 4 transects (3 frames/transect = 12 frames); WV+BH total = 1,162 colonies
– Dive Centre – 2 transects (73 colonies on the pyramids);

Overall, we will be monitoring 3 genera (Acropora, Pocillopora, Porites) totalling 34 different species (although 29 are Acropora). Bleaching surveys will continue every 2-3 weeks throughout the bleaching season, to monitor the impacts on our Reefscapers coral reefs. Our initial surveys have identified some light paling and fluorescing, with little-to-no bleaching so far (score of ‘2’: 1-10% colony bleaching averages for all monitored species).

Reefscapers at Sheraton Maldives [SM 2024.02] NOAA CoralWatch

NOAA’s CoralWatch bleaching alerts for the Maldives (29 March). As warmer ocean currents arrive from the South, we flipped from ‘Watch’ to ‘Warning’ this month. The forecasted ‘degree heating weeks’ will rise through May-June, with many corals expected to bleach in the coming weeks, country-wide.
Widespread coral bleaching has already hit Florida (2023) and the Great Barrier Reef (Feb-April 2024) – see our Climate resources.

Reefscapers at Sheraton Maldives [SM 2024.02] coral reef restoration

Our coral maintenance work, health/growth observations and monitoring photos have kept our small team busy this month at all our reef regeneration sites around the island.

  • At the Blue Hole site – the frames are growing well, but seasonally shifting sands continue to be an issue on the NE side, and regular lifting is necessary. Some frames were rearranged, and moved away from the steep slopes where they are less threatened by sand. The fish population continues to grow, with large schools of resident snappers, goatfish, and parrotfish. Juvenile fish are also being regularly seen, including boxfish and the elusive emperor angelfish. A HOBO temperature logger was placed here on 21 March, to accurately record water temperatures.
  • Water Villas – some paling and fluorescing was observed on these frames this month. The current has been strong, which we hope will continue to bring cooler water into the area over the coming months. We are preparing to shade these frames if and when required. Two small corallivorous crown-of-thorns were removed from two different frames, largely populated with Acropora muricata colonies.
  • Gili’s Falhu – frames are healthy and growing well at depths of 3-5m. Bleaching monitoring will be conducted on an ad hoc basis, in conjunction with maintenance visits. If the frames show strong signs of bleaching, we will move them into deeper waters.
  • Boat Garden – New coral frames continue to be added, at depths of 10-12m. These have been monitored to assess how successful this site supports coral fragments. Growth of macroalgae is low, which is beneficial to newly transplanted fragments, and the fish population surrounding the boat will help with grazing. Overall, the frames planted over the last 2 months are thriving and will be closely monitored.
  • Dive Centre Frames – fragments have been attaching and encrusting well, and the frames are healthy and continue to grow. Some 6-month old frames were monitored this month via scuba dives, in conjunction with pyramid maintenance. The presence and growth of macroalgae and Ascidians (sea squirts) continues to be an issue, and they both need removing regularly to prevent competition with our corals
  • Dive Centre Pyramids – Several maintenance dives were conducted, to check the well-growing pyramids. We removed a few Drupella snails, and there are no signs of coral paling or bleaching. A HOBO temperature logger was placed here on 21 March and will start to record ocean temperatures.
  • Lagoon Pyramids – due to the relatively shallow warm waters, these pyramids are potentially vulnerable to the warming ocean temperatures. Coral colonies remain colourful and healthy, but we are monitoring closely and regularly.
Reefscapers at Sheraton Maldives [SM 2024.02] coral monitoring
Reefscapers at Sheraton Maldives [SM 2024.02] coral maintenance

Reefscapers Visitors – On 21 March, we were delighted to welcome Carlo (marine biologist) and Ellie (coral biologist), our colleagues from Four Seasons Resort Kuda Huraa (pictured above). After touring the pyramids and the Blue Hole site, we discussed coral maintenance tasks, and techniques to help with coral mitigation ahead of the bleaching season.

Marine Life – In total, 23 guests attended our Maldivian Journey Snorkelling activity this month, averaging 6 people per 65-minute session. Feedback remains positive despite the earlier time slot, and guests are extremely impressed by the pyramid structures and diversity of marine life around them. We conducted 4 Snorkel Safaris and 4 Reef Snorkels, with megafauna sightings including porcupine rays, spotted eagle rays and abundant blacktip reef sharks. During the 7 Dolphin Cruises this month, we successfully sighted Spinners on every trip, and our resort colleagues reported sighting a small pod of pilot whales nearby.
A green turtle has become a regular visitor to the Sheraton Maldives, visiting a particular sea grass patch for 1-2 hours every day. We have also enjoyed the company of a less-common blotched fantail ray (Taeniurops meyeni), accompanying us during our coral work and entertaining the snorkelling guests.

Marine Talks – we conducted 15 presentations this month, totalling 74 guest attendees (a large increase from last month). Our talks averaged 47 minutes with numerous engaging questions, and generating 5 coral frame sales. A special talk was given for World Wildlife Day, enjoyed by 12 guests, as we presented some amazing animals from around the world (not limited to marine life).

Reefscapers at Sheraton Maldives

Yellow boxfish … we have the cutest of marine friends! 💛 

Reefscapers at Sheraton Maldives [SM 2024.02] fish soup

This is the only kind of fish soup that we enjoy 💙 

Artificial reefs at Sheraton Maldives

SH001 was the first frame transplanted at Sheraton in February 2020 (sponsored by the resort)

Artificial reefs at Sheraton Maldives [SH001 2yo]

Growth of SH001 after 2 years …

Artificial reefs at Sheraton Maldives [SH001 3yo] SH001H00230704

… after 3 years … 

Artificial reefs at Sheraton Maldives [SH001 4yo] SH001H00231211

… and coming up to 4 years old. 💜