It’s great to be alive! Freediving on the reef.
Erin's Monthly Marine Musings
‘Teamwork makes the dream work’ has been our mantra at Kuda Huraa this month! Between our two apprentices, two interns, and four marine biologists, we’ve been working solidly on all our projects around the island. And it’s been crazy fun to have so many hands working underwater every day, whether it’s transplanting corals or monitoring frames or guiding snorkels (triggerfish attacks aside!). We ran out of workstations in the office during stormy weather… a good problem to have! It’s a great feeling to be working alongside friends, all driven by a passion towards a greater purpose: saving the reefs.
We had the pleasure of welcoming Kate, the Sheraton Marine Biologist Extraordinaire, to our island for a day of collaboration. Erin also had a short-but-sweet day trip to Landaa, shadowing Simon and the team – what a great operation they run! Individually, we’ve all found our niches, focusing on our various strengths, learning and growing collectively as part of the larger Reefscapers family.
Our small team is but one drop in a vast ocean; with so many marine creatures needing help, and only so many hours in the day, we continue to prioritise the essential tasks over the merely urgent. Practically, there’s a tendency to overestimate daily accomplishments, but underestimate annual progress… We all have the power to save this planet through the actions we take and the choices we make – individually we can do a lot, but together we can achieve even more.
You are not a drop in the ocean. You are the entire ocean in a drop. – Rumi
Fish Lab & Aquaria – Marine Life in the Maldives
Large Marine Aquarium
During June, our large 4000L display aquarium went through an overhaul. The pumps were removed and deep cleaned, with all algae and CCA removed, before being returned to the tank and adjusted to optimise flow. Any broken rock and discarded shells were removed from the substrate; the sand was siphoned to remove waste, algae, and anoxic sediment. We then added many new corals, fish and invertebrates, including:
- torch coral (Euphyllia glabrescens),
- mixed Tubastraea species,
- several Goniopora colonies,
- large giant clam (Tridacna maxima).
We adjusted the lighting system to follow a preset cycle, with a higher percentage of blue light in the spectrum, peaking in the afternoon. This is designed to promote coral growth and reduce stress levels, as well as inducing low levels of fluorescence. Blue light is absorbed very well by the chlorophyll in the zooxanthellae to increase photosynthesis, which will help the corals and the clam (also photosynthetic). Tubastraea corals are non-photosynthetic night-time filter-feeders, and unexpectedly they have now started to extend their polyps in the blue light of late afternoon, thereby increasing their feeding period.
Anemonefish with anemone out on the reef, photographed on snorkel safari
Algae supply remains on a consistent and successful cycle. Due to the demands of new filter-feeders in the main aquarium, we have increased our Artemia production. Despite using the same daily volume, we are now hatching a total of 6g of cysts rather than 4g.
This month, the rotifers suffered a decline in numbers, partly due to due to a small hole in the filter mesh, and also down to new staff training (the delicate balance of washing and feeding caused a gradual loss with each wash). The mesh has been replaced, the training improved, and we are currently on a high-feed period to increase the population.
Zooplankton Survey Study
As part of our Zooplankton Survey, one of our apprentices collected a sample of plankton slick from the lagoon. Interestingly, the sample turned out to be the mid-larval stage of the brachyuran crab (Brachyuran megalopa), commonly seen around the island.
Jellyfish – Aurelia aurita
In June, we drained and thoroughly cleaned our display Kreisel cylinder. Several power outages stopped the water flow during the month, resulting in small deformities in the bell and tentacles of some of the jellies. All jellyfish in the Fish Lab continue to grow in the sump-based system, following our established protocols (30% water change every other day).
🦇 The MDC Goes Batty! 🦇
In addition to our marine conservation work, we have recently diversified into caring for two juvenile fruit bats. Both were found on the ground after falling from trees during the recent rainstorms. At around six weeks of age, they would be entirely dependent on their mothers for care, but after several hours they were not reclaimed from nearby bushes.
Both bats are doing well despite not having access to their mothers’ milk, and they successfully transitioned onto a diet of fruit a little earlier than normal. The young male has become very bold, exploring the surroundings and exercising his wings. The female is a few days behind in development. We aim to release them both once they can fly.
Ornamental Fish Breeding
- Clark’s clownfish (Amphiprion clarkii) –The single larva from May has now fully metamorphosed into a juvenile fish, with full colouration. It has been introduced to a small anemone in Tank #38, transitioned onto a 12hr/12hr lighting cycle, and has started hosting. Following the deep cleaning of Tank #3, the pair are now laying again after a two-week break. But the stress of the tank clean weakened the latest clutch, and only two larvae survived the first week.
- Maldivian clownfish (Amphiprion nigripes) –The pair in the main tank continue to breed well, with two spawning events. The first clutch was lost, so the second clutch and breeding pair were relocated to breeding Tank #21. Despite this disruption, the eggs developed well and hatched on the predicted date, producing 20 larvae that are currently being monitored. After hatching, the pair and their anemone were returned to the main tank.
- Sexy shrimp (Thor amboinensis) – The clutch produced by our breeding female (A), and her partner at the start of May continue to do well, with a total of 30 larvae in development stages #7/8 (showing signs of settlement). This pair produces well, with a clutch of 300 larvae every 12-14 days.
Our smaller breeding female (B) and her partner also produce well, with a clutch of 90 larvae every 13-15 days.
Two of the male shrimps collected during May underwent metamorphosis, transitioning from male to female, so we now have four females and two males. These new females (C and D) are now reproductively active, with C spawning a clutch of 267 at the end of the month, and D carrying eggs. - Boxer shrimp (Stenopodidea) – The boxer shrimp successfully hatched a clutch of eggs on 2 June; the larvae were collected and transferred to a separate rearing container. This proved successful up to day-14, with minimal mortality and good development, but by day-18 the clutch was lost to predation within the larvae. To counter this, we plan to increase feed concentrations from day-10, and reduce the larval concentration using a larger container.
The pair produced a new clutch on 26 June, totalling 52 larvae that started showing adult banded colouration from day-2 (see photos).
Fish lab Brachyuran megalopa larva
Brachyuran megalopa larva
Fish lab Boxer shrimp larva development (Stenopus hispidus)
Boxer shrimp larva
Fish lab Boxer shrimp larva development (Stenopus hispidus)
Boxer shrimp larva
Fish lab Boxer shrimp larva development (Stenopus hispidus)
Boxer shrimp larva
Maldives Sea Turtle Rescue & Conservation
Sea Turtle Rehabilitation
At the close of June, we were caring for three Olive Ridleys (Lepidochelys olivacea), one Hawksbill (Eretmochelys imbricata), and one Green sea turtle (Chelonia mydas) in our Rehabilitation Centre at Landaa.
At Kuda Huraa, we continue to care for Ari (52.6cm, 18.4kg), our amputee Olive Ridley patient who this month became the star of the Marine Savers Instagram page! (see right) We posted a video of her ocean swim to commemorate ‘World Sea Turtle Week’, which soon clocked up thousands of views and hundreds of likes.
Ari enjoys her ocean swims as an integral part of her enrichment that benefits her buoyancy rehabilitation. A new scratching post has been introduced in Ari’s tank, and she has already been spotted using it, and resting underneath it.
Wild hawksbill turtle swimming on reef
Project: Sea Turtles and Environmental Enrichment for Rehabilitation
One of our current research projects is looking at the use of environmental enrichment in sea turtles, an important component of effective rehabilitation before return to the wild > READ MORE
juvenile Olive Ridley UNO is skilled at taking food from the pipe dispenser, and can empty it in under a minute!
Long-term resident, female Olive Ridley MAW interacting with a log, and recorded on video as part of our EED experiment.
UNO again, enjoying a snooze on the water surface while resting inside the floating square ‘pool toy’.
Maldivian Sea Turtle Identification Program
During June, we received 9 submissions of photo sets from the public to our Sea Turtle ID project (8 different Hawksbills plus 1 Green turtle).
Our current database now catalogues 5,200+ separate sightings, across 16 different atolls of the Maldives. To date, we have positively identified and named a total of: 1346 Hawksbills, 282 Greens and 95 Olive Ridleys.
We have started trialling a new recognition software that uses the Citizen Science Wildbook ‘Internet of Turtles’. Photos of individuals that are not recognised using I3S software were added to this database to search the wider local network for a match.
The trial also involves comparing the recognition success rate of I3S verses IoT using individuals with multiple images that have been sighted many different times. The trial is being conducted with the goal to establish one database for the whole of the Maldives’ turtle population.
Spotted a turtle? Share your photos
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 World Sea Turtle Week, we hosted a competition to promote our turtle identification project and to bring more attention to the Facebook page. The competition ran for a week, with nine of the best photos (pictured) from the last year competing to receive the most Facebook ‘likes’.
The winner’s photo was posted to Instagram, and is now featured as our Turtle ID Facebook page banner (pictured).
Turtle ID photo submissions
Turtle ID photo winner ‘Koho’
REEFSCAPERS Coral Propagation & Reef Restoration in the Maldives
Alejandra, our Reefscapers coral biologist, Kuda Huraa
Relocating our artificial reefs, Landaa Giraavaru
Monthly Progress
At Landaa during June, we transplanted 2000 coral fragments onto 33 new coral frames (17 guest-sponsored, 14 Resort-sponsored, 2 online orders).
At Kuda Huraa this month, we transplanted 8 new coral frames using 500 coral fragments. We continue to monitor our Gulhifalhu rescue colonies for health and growth, and relocated 30 frames that became partially-buried by sand.
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.
You may also be interested in our ongoing research and photography, studying coral spawning.
Reefscapers rescue corals soon increase marine biodiversity in the lagoon
Further News & Updates
You might also be interested in:
– our ongoing Dolphin ID Project,
– our unique 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.
Pan-tropic spotted dolphin – very rare sight in Maldives!
Photographed as part of our ongoing Dolphin ID Project
