Heart-shaped Reefscapers coral frame #RK0047 at Kuda Huraa, planted in December 2020 and photographed here in February 2023.
Margaux, our coral biologist at Landaa Giraavau, transplanting coral fragments onto a newly sponsored Reefscapers coral frame.
REEFSCAPERS Coral Propagation & Reef Restoration in the Maldives
Monthly Progress
At Landaa during February, we transplanted 38 new coral frames, kindly sponsored by guests (18), the Resort (11), and and online orders (9), which added more than 2,000 new coral fragments onto the reef. In addition, we monitored (cleaned, repaired, photographed) 208 coral frames at various sites around Landaa Giraavaru.
We have also repaired frames at the Turtle site and Bissie’s Reef (using 1970 fragments), and lifted 252 coral frames that had become buried in the seasonal shifting sands (at the Turtle and Blue Hole sites).
At Kuda Huraa, we monitored a total of 164 existing frames, retransplanted 40 existing frames, and transplanted 8 new frames around the island, kindly sponsored by guests (4), the Resort (1), and online (3).
Also this month, our team spent time maintaining the House Reef site. Over several dives, we lifted 60 coral frames from the seasonal shifting sands, retransplanting them with new coral fragments as we went. The House Reef is a challenging site to maintain – the depth necessitates SCUBA gear, many of the frames are untagged and arranged randomly, and there are many corallivores due to the healthy biodiversity. This means the whole operation requires a coordinated team effort, usually during low season, with one team member remaining with the boat.
Valentine’s Day! 💙
On 14 February, we organised an event with our Resort colleagues to build a commemorative heart-shaped coral frame.
Ale, our coral biologist at Kuda Huraa, studying settled juvenile corals in our pioneering work on coral sexual reproduction.
Read our Reefscapers Diaries for further details and photographs of our ongoing coral propagation efforts and reef regeneration experiments, both in the Lab and out in the lagoon, updated each month.
Fish Lab & Aquaria – Marine Life in the Maldives
Plankton Production
- Algae – is consistently cycling at full volume
- Artemia – production is keeping up with the demand of the main tank at 5g of cysts a day, with one 100L algae tub containing Artemia nauplii for grow-out
- Rotifer – volumes remain consistent and stable.
Zooplankton Survey Study
We are working on the new net trials for our Zooplankton Survey. During February, we are still observing high levels of bioluminescence on the beaches all around Landaa, caused by the presence of ostracods, and mid-water bioluminescence caused by Noctiluca.
Jellyfish
All jellyfish (Aurelia aurita) in the large Kreisel cylinder continue to thrive, with no signs of damage or shrinkage. The water quality has improved following the introduction of the new UV steriliser.
We think our unidentified juvenile jellies are sea nettles (Chrysaora fuscescens), although we have now lost most of them as we attempted to optimise their environment. The remaining two specimens have now developed into early-stage medusa that are growing well, so the new environmental conditions have proved effective so far. They are developing a reddish/brown hue in the bell, along with stinging tentacles and frilly oral arms, thereby further supporting our identification as sea nettles.
Megafauna and Marine Life
This month, we were excited to identify two different species of hammerhead sharks, namely the scalloped hammerhead (Sphyrna lewini) and the great hammerhead (Sphyrna mokarran).
On our dive excursions, we continue to see plenty tiger sharks (Galeocerdo cuvier), bull sharks (Carcharhinus leucas) and spinner sharks (Carcharhinus brevipinna). Surprisingly, the presence of these large apex predators does not seem to deter the smaller species, and we still see masses of pink whiptail stingrays (Himantura fai), plus mobula rays across several snorkel sites around Kuda Huraa. We think these are likely to be juvenile/sub-adult spinetail devil rays (Mobula mobular) with wingspans of 100cm (adults can reach 320cm).
Within the waters of South Malé Atoll, we have recently observed large numbers of a ribbon-like ctenophore (translucent, gelatinous, with cilia). The ‘Venus girdle’ (Cestum veneris) is technically a comb jellyfish, uniquely the only member of the Cestum genus. The comb rows produce a beautiful rainbow effect as they move, scattering light [video]. Being a predatory organism, they are vital in controlling the numbers of small zooplanktonic organisms, such as copepods.
International Day of Women & Girls in Science, 11 February 2023.
Our team at Kuda Huraa marking the day
Scalloped hammerhead, N.Malé Atoll
Ornamental Fish Breeding
We plan to scale back our fish breeding, allowing us to expand our more successful research on shrimp breeding.
- Clark’s clownfish (Amphiprion clarkii) – There were three spawning events in February, however, they were eaten by the parents prior to hatching. We have attempted to vary parental diet to prevent this, with no success. The breeding pair in Tank #2 continue to show signs of nesting inside their flower pot, although there has been no spawning yet.
- Maldivian clownfish (Amphiprion nigripes) – Still no signs of breeding from our pairs in the Fish Lab, however, the pair in our main display aquarium continue to lay (but collection of the larvae is difficult).
- Sexy shrimp (Thor amboinensis) – Research continues for publication. A total of seven clutches have now been collected since the start of the year, with three hatching in February. This has produced almost 1000 larvae between the two clutches, which are developing well. The December clutches continue to settle and grow, producing 17 settled and semi-mature juveniles. The two January clutches have all been moved to holding buckets and introduced to settlement stimulus (average survival to settlement is 32%).
- Boxer shrimp (Stenopus hispidus) – Three clutches produced this month, and observations continued on ovary development and reproductive cycle.
- Camel shrimp (Rhynchocinetes durbanensis) – Seven clutches from our three breeding females.
- Skunk cleaner shrimp (Lysmata amboinensis) – Research continues and has demonstrated a clear pattern for analysis. We also managed to collect a total of 734 larvae from the two shrimp.
- Mantis shrimp (Odontodactylus scyllarus) – The new resident has settled in, actively hunting for food around the tank, and is even interacting with guests through the glass. He is also showing signs of an imminent moult, so we have added loose rocks to his environment. As a result, there has been a flurry of building work as the shrimp resizes the rocks, in anticipation of sealing the burrow when it is time for moulting.
‘Sexy’ or ‘dancing’ shrimp (Thor amboinensis)
‘Boxer’ shrimp (Stenopus hispidus)
Further News & Updates
You might also be interested in:
– our ongoing Dolphin ID Project,
– our specialised Sea Turtle Lagoon Enclosure, and
– our Zooplankton Monitoring Project (launched in 2021).
Looking for details of our Reefscapers coral propagation and reef restoration program ? Then head over to our Reefscapers Diaries for all the latest updates.
You can sponsor your own frame and see photographs (updated every 6 months) in our Coral Frame Collection.
Junior Marine Savers activities: (1) Reefscapers corals, (2) turtle care.
International Day of Women & Girls in Science, 11 February 2023.
Dr Kat (left) and Margaux at Landaa’s Marine Discovery Centre
International Day of Women & Girls in Science, 11 February 2023.
Helen our Marine Aquarist, testing a zooplankton sampling net
