Like dolphins ? So do we ! Be sure to visit our Dolphin ID project page for more great photos and video.
Fish Lab & Marine Aquaria
It’s time for the periodic renovation of our large marine aquarium, which has been suffering from detritus build-up and some coral mortality of late. All the marine life was safely released back into the ocean, and the rock structure substrate removed. The tank then underwent a thorough clean before new rockwork and substrate was added. The new aquascape was created using PVC piping to support the rock structure, and designed for maximum water flow throughout the tank.
The tank will be re-established over the coming months, initially as FOWLR (fish only with live rock) allowing us to exhibit larger fish specimens (potentially: Pygoplites diacanthus, Pomacanthus imperator, Naso lituratus, Zebrasoma desjardinii, Zanclus cornutus, Arothron diadematus, Panulirus versicolor, plus species of Chaetodon and Acanthurus).
The tank will run with minimal stock for at least a week to allow any NH3/ NO3/NO2(-) to be removed, caused by live rock die-off. Stock will then be chosen and added slowly, with the largest inhabitants added last.
We performed the renovations from 26 October to 8 November. Our new FOWLR display showcases selective fish stock amongst natural live rock, colonised by a variety of marine life (sponges, invertebrates, beneficial nitrifying bacteria). A natural-looking environment was created, with supplemental filtration to help optimise circulation and maintain a stable eco-system. The aquarium now showcases a diverse range of local marine species to provide an eye-catching display for guests as they enter our Marine Discovery Centre.
By the end of November, we had added a total of 148 marine animals into the aquarium, encompassing 38 species from across 19 families of fish, arthropods, echinoderms and molluscs. This diverse population provides an exciting attraction and educational resource, with a pleasing spectrum of colour and wide morphological and behavioural diversity (schooling & solitary fish, predators, foragers & filter feeders, adult & juvenile forms):
- Oriental sweetlips, Racoon butterflyfish, Picasso triggerfish, Naso Tang, Sailfin Tang, Blue-green chromis.
- Naso literatus, Rhinecanthus aculeatus, Zebrasoma veliferum, Chaetodon lanula, Plectorhinchus vittatus.
Water parameters are stable; salinity levelled at 32.3+/- 0.00 with an average temperature of 28.9°C+/- 0.00, which provides comfortable conditions within the main aquarium and Fish Lab tanks.
We now have two Sargasso Frogfish (1 juvenile and 1 adolescent), naturally very well camouflaged and sedentary, making a fun and educational opportunity for younger guests to attempt to spot them within the tank. We also have a Lionfish specimen, currently in quarantine and getting accustomed to feeding in the new environment before introduction into the main aquarium.
The mini coral frame has some encrusting growth of Acropora coral fragments, and the mysterious green colouration seems to be spreading but does not show any adverse effects on the fragments themselves. Two of the fragments at the bottom are partially bleached (likely due to sedimentation and reduced light) so we have repositioned the frame to maximise light intensity for all fragments. Any dead/bleached fragments have been replaced, some of which have shown initial paling. Multiple fragments of A. digitifera and A. hyacinthus have now encrusted over both the zip tie and the rebar, and A. tenuis is growing particularly well.
The mature Maldivian anemonefish (Amphiprion nigripes) laid eggs at least twice during October; we monitored them closely, and observed a sample under the microscope. By day 5, the yolksac was reduced, production of dendritic melanophores were visible, and we observed heartbeat/muscle contractions (Krishna et al. 2018).
We have a tiny new specimen of juvenile soft coral (thought to be Sarcophyton species), currently just 3mm in height.
The two large Clark’s anemonefish (Amphiprion clarkii) were observed laying and fertilising eggs on 26 November. However, by Day 3 there were significantly fewer eggs, and despite the parents’ diligent efforts at care and cleaning, the eggs were presumed to have been predated by another species in the tank.
Kreisel Jellyfish Tank – Aurelia aurita
Our Aurelia aurita are continuing to grow in size (both mass and bell diameter), and have been well acclimated in our Fish Lab from the more usual 25°C, to thrive in the warmer environment of our Kreisel aquarium, which remains stable at 27.8°C due to the nature of its closed system. We currently have 24 medusae on display, comprising 23 medium-size adults and one abnormally large individual.
The smaller specimens are being reared in the Fish Lab Kreisler until they reach a larger size for display. The jellyfish polyps (scyphystoma) have been cultivated onto 4 plates for extensive growth, so that enough stock was attained to allow for the preliminary incubation and acclimation period to have commenced, preceding the ‘environmental shock’ stage at which point the scyphistoma will metamorphose into strobila and produce small ephyrae.
We currently have 3 breeding pairs of Clownfish down in our fish lab, all being fed krill on a daily basis to improve fecundity and egg health:
- Clark’s clownfish (Amphiprion clarkii) – currently spawning once/month, on average;
- Maldivian or blackfinned clownfish (Amphiprion nigripes) – spawning 1.5 times/month;
- Common clownfish (Amphiprion osellaris) – spawning twice/month; fewer eggs/batch, and the doting parents over-preen, leaving few eggs to develop to the hatching stage.
Linckia multifora sea stars
We continue to monitor and observe our Linckia multifora sea star specimens.
The autonomised arm in the comet phase showed a total length of 46mm, and the new arms were consistent with lengths of 7-8mm, indicating the growth rate had slowed (growth slows between 6-10 months to a length of 10mm [Edmondson, 1935]).
The larger “disc parent” had an average increase in arm length of 1-2mm/month, excluding the new arm which stayed the same this month.
The large L. multifora (aquarium two) showed minimal growth; the new autotomised arm appears to be healthy and has been observed in different locations around the aquarium, indicating its health has not been affected by the relocation. Whilst its total length has remained similar to last month, it is now possible to observe yellow-coloured tissue on the ventral side of the arm. This indicates the development of the ‘germinal crescent’ which facilitates growth of new arms, and suggests the arm has been separated from its disc parent for roughly six weeks (Edmondson, 1935). Based on the comet phase of our original sea star, which had developed new arms within 12 weeks of separation from its parent, we expect to see new arm growth within six weeks.
Education & Awareness
Four Seasons Maldives Apprenticeship Program
As part of the Four Seasons Maldives Apprenticeship Program, semester 2 of our marine biology module, our apprentices were tasked with reviewing a selection of scientific articles. They were taught the important components that make up an article, and how to evaluate the research. The 6 apprentices have been practising their public presentations skills and creating effective PowerPoint slides on their work to date, including introductions, materials and methods, and their chosen articles (ranging from Maldivian manta ray feeding patterns, to the abundance of Indian Ocean marine life). They will make final presentations to the Marine Savers team at the end of the semester.
We also started recruiting enthusiastic local Maldivian candidates for the Apprenticeship Program 2020. We interviewed 9 applicants, and will be selecting 3 lucky candidates to start their marine education program with us next year.
In November, we welcomed 22 students from Eydhafushi School, as part of the Manta Trust’s “Moodhu Madhanisaa” (‘Ocean School’) awareness scheme. The students enjoyed a tour of our facilities, encompassing the Turtle Rescue Centre, fish and aquaculture lab, and a hands-on demonstration of our Reefscapers coral propagation program. We also gave awareness presentations on marine life and conservation efforts in the Maldives.
REEFSCAPERS Coral Propagation Program
New Coral Storage Tanks
Our 4 new fibreglass tanks were delivered this month, and installed with sand-filters and adjustable flow-rate mechanisms. We can now store many more coral fragments, and for longer periods of up to 5 days (less during the warmer months of March-April.) We have also successfully housed some of our clown fish brood stock and sea anemones in the tanks.
Read more coral propagation news in our Reefscapers Diary.
AI / Catamaran
We have ordered some replacement propeller parts, prepared a designated parking area on land, and will be working on a custom-designed trailer for transport to the ocean.
Our deep-learning model has now been trained on almost 400 coral frame photographs, comprising more than 6,000 individual pieces of coral, and is now relatively accurate at detecting and identifying corals. Next, we are using successive image processing algorithms to detect the metal bars, to then extract the shape of the frame for precise positioning of the corals on the structure.
Read more in our Diary and then head to Reefscapers for more photos & videos, and the full project history.
White Fire Exhibit
We were invited to the “White Fire” art exhibit in Malé (21-24 October), created to highlight the importance of banning coral poaching around the Maldives. Our Reefscapers team presented our coral propagation program, with details on the latest technological improvements.
Sea Turtle Conservation
Sea Turtle Enclosure
During October, we installed the new net for our sea turtle enclosure (installed in the lagoon at Landaa) and we were then able to house Tiff there, who soon started to make good progress with her swimming.
During November, we introduced Hailey into the enclosure, and she soon started getting along with Tiff. Hailey proved she was good at diving, and was successfully released back into the ocean on 17 November. Tiff is currently doing well, practising and improving her diving.
On 9 November, we conducted a deep clean of the netting to remove the fast-growing algae, and plan to repeat this monthly to prevent fouling, keeping the enclosure functional and increasing its durability and lifespan.
Read more about our unique turtle enclosure, and how it’s helping in the rehabilitation of our turtle rescue patients.
This time of year has been dubbed ‘sea turtle stranding season’, when we see increased numbers of entangled turtles being carried into Maldivian waters by seasonal oceanic currents from the direction of Sri Lanka, India and Indonesia.
The so-called ‘ghost nets’ consist of discarded fishing gear, usually of the types not seen in the Maldives, where fisherman use traditional pole-and-line methods to catch tuna (as well as fine filament nets to catch their tiny bait fish, commonly sprat and anchovy). These ghost nets attract sea turtles on the search for food; their flippers are easily entangled in the net filaments, causing severe damage and ultimately the death of the animal. It is mainly Olive Ridley turtles that become stranded, a species that is otherwise not normally seen in the Maldives.
See the corkboard (below) for photos and links to our resident turtle patients, which we keep updated with our new arrivals and releases.
At Kuda Huraa, we have:
– 5 Olive Ridley turtles (Lepidochelys olivacea) and 2 Hawksbills (Eretmochelys imbricata) rescued from entanglement in drifting ghost nets, and under treatment in our turtle recovery pools.
– 7 Green turtles (Chelonia mydas) and 6 Hawksbills in the Hatchling Rehabilitation Program (HRP).
And at Landaa:
– We rescued 4 new turtles this month, and released 1 recuperated turtle back into the ocean (Hailey Armand).
– We currently have 10 Olive Ridleys and 1 Green sea turtle in our Rehabilitation Centre.
– We are at maximum capacity, with all pools occupied, so we started using our new coral storage tanks to admit new patients for quarantine (which is working well).
PEGGY’s EPIC JOURNEY! 2014 MV ⇄ EU 2019
Read how Peggy returned from Belgium to be released back into the wild here in the Maldives, on 21 June 2019. Guests, staff and media were able to be part of her story, as she swam around the lagoon before heading north in North Male Atoll.
Peggy’s satellite signal stopped on 8 November, after transmitting for a total of 142 days (maybe the satellite tag was dislodged, or the battery could be exhausted). Her last transmission was 182km off the coast of India, in the Bay of Bengal (interactive map). Her trajectory of 5771km shows she returned for mating and nesting on the coast of India.
Work towards the next wave of ‘Flying Turtles’ is continuing. We are trying to find permanent overseas homes for the unreleasable Olive Ridley turtles that have been in our care for more than 1 year. They are missing flipper/s (from entanglement in ghost nets) and suffering from buoyancy syndrome (unable to dive below the water surface) which means their ability to survive out in the ocean is permanently compromised.
We are in regular contact with aquaria in both the UK and South Africa, who wish to provide a permanent home for several of our Olive Ridley turtles. Agreements are being finalised, and we are completing the turtle health checks necessary for approval from the Government of Maldives.
Maldives Sea Turtle ID Project
Turtle photographs are kindly sent to us from members of the public and from fellow marine biologists stationed at other resorts around the Maldives. Submissions consist of close-up photographs of the turtle facial profile, enabling us to outline the unique pattern of scales (scutes) that act like a human fingerprint.
During October-November, we received an impressive 53 submissions from the public around the country to our Maldives national turtle ID project. (THANK YOU!)
Currently, our database contains 1199 Hawksbills, 207 Greens and 56 Olive Ridleys.
[PHOTO: Hawksbill turtle EI1167].
Spotted a turtle? Share your photos
Further News & Updates
You might also be interested in our Dolphin ID Project, and our Sea Turtle Enclosure out in the lagoon at Landaa.
Looking for details of our coral propagation programme ?
Head over to our Reefscapers 2019 Diary for all the latest updates.
You can sponsor your own dedicated Coral Frame, and then see how it grows in the future by viewing the photo updates every 6 months, as part of our Coral Frame Collection.
Photos: (1) Reefscapers coral frames at Kuda Huraa water villas.
(2) Junior Marine Savers learn the importance of corals.