Reefscapers coral frames contribute to the amazing biodiversity of the natural reef (larger photo below)
Fish Lab & Marine Aquaria
Plankton Production
Artemia provide an essential food source for our juvenile clownfish, jellyfish and seahorses, and our Fish Lab production continues successfully. This month we saw a decline in average Rotifer concentrations (down from 218/ml to 168/ml) probably due to a return of ciliates within the population. Ciliates are protozoans with hair-like appendages (cilia) used in movement. Their diet is primarily bacteria and algae, therefore, due to the clear lack of algae within our Rotifer population, the growth of ciliates is likely due to bacterial bloom. This may be due to excess yeast (Rotifer food) or potentially additional bacterial numbers within the seawater used to wash and replenish the Rotifer environment. Whilst all the seawater used in conjunction with Rotifer production is filtered before use, small amounts of bacteria may be present due to bacterial blooms caused by changing environmental conditions. The presence of ciliates is managed by increased cleaning schedules, with regular monitoring to adjust the feeding and cleaning schedules accordingly.
Clownfish breeding
No eggs were produced this month, but all of our 49 Clark’s Clownfish juveniles are healthy and continue to grow well.
Small Aquarium One
Mini coral frame – the five remaining living coral fragments are healthy.
On 19 August, our breeding pair of Maldivian anemonefish (Amphiprion nigripes) laid eggs for the first time. We will continue to monitor this pair in the upcoming months.
Small Aquarium Two
Mini coral frame (Acropora digitifera) – two of the fragments died this month, whereas the others are growing well and encrusting onto the frame.
The colony of Galaxea fascicularis is healthy and growing well, and has now encrusted onto the wall of the aquarium.
Our breeding pair of Clark’s anemonefish (Amphiprion clarkia) laid three separate batches of eggs this month. Before they could be eaten by the aquarium inhabitants, we examined the various developmental stages under the microscope.
Linckia multifora sea stars
SS1 (large specimen) – a small decrease in the length of two arms was recorded.
SS3 (large specimen) – growing at a slower rate.
Amphiprion clarkia fish eggs
Amphiprion clarkia fish eggs
Amphiprion nigripes fish eggs
Jellyfish – Aurelia aurita
Our jellyfish production continued well for the first weeks of August. The ephyra transitioned to juvenile medusa, so we relocated them from tank [#1] to a larger growing Kreisel tank [#2] where they were fed twice daily and received twice-daily 100% water changes. Their growth rate was good, so we relocated them to another larger Kreisel tank [#3] with more space to grow. Following the transfer, however, around 200 of the original 250 medusae began to deteriorate in health and stopped swimming (the exumbrella began to detach from the rhopallum). As such, we returned the 50 healthy medusae to their original tank [#1], and the 200 unhealthy individuals to the growing tank [#2] with twice-daily feeds and water changes. Unfortunately, the 200 individuals declined further and became listless on the bottom of their tank.
After additional research, we deduced this decline in health was due to a change in salinity between aquaria. Salinity is attributed to maintaining their “bell” shape. However, this species of jellyfish is able to adapt to brackish water, but appear flatter under these conditions. A change in salinity at this stage of development may have caused a shift in growth pattern and ultimately the breakdown of tissue.
The remaining 50 jellyfish were housed in their original tank for an additional week, with the salinity regularly monitored and adjusted as necessary. They continued to grow well and soon became too large for the small Kreisel. A new tank was set up using an aquarium pump to generate flow in a closed system, with the appropriate salinity and temperature achieved. Unfortunately, once relocated, the jellyfish underwent the same process as their predecessors and began degrading in the water column. In the space of 12 hours we lost the remaining 50 jellyfish. We have theorised that the problem may come from some of the equipment used in their new holding tank.
We have now begun strobilating [*] additional polyps to repeat the process, and have established a small filter system in the holding tanks and will attempt to minimise the movement between tanks as growth allows.
[*] Strobilation is defined as asexual reproduction by transverse division of the body segments which develop into separate individuals.
REEFSCAPERS Coral Propagation Program
A ray, spotted hiding between our coral frames, Kuda Huraa
Monthly Progress – August
At Kuda Huraa, we monitored (repaired and photographed) 40 coral frames, and cleaned a further 353 frames, ready for transplantation later in the year.
At Landaa, we monitored 115 frames, transplanted 21 new coral frames (thanks largely to a very generous online donation).
This month, our time-lapse experiment was successful for a second time, as we filmed the actual moments of gas release during the bleaching process. We are also continuing with our research to study coral resilience and coral propagation techniques, including coring (in the lagoon) and reproduction (in the lab).
Check out our 2020 Diary for further project details and all our latest photographs.
Transplanting coral fragments to a Reefscapers coral frame
Transplanting coral fragments to a Reefscapers coral frame
We regularly clean, maintain and photograph our coral frames
We regularly clean, maintain and photograph our coral frames
Our loggers record 24/7 the sea surface temperatures in the lagoon
Our loggers record 24/7 the sea surface temperatures in the lagoon
Monitoring the status of wild coral colonies on the reef
Monitoring the status of wild coral colonies on the reef
Our ‘table’-shaped frames are designed for shallow waters and are popular nurseries for fish and marine life
Sea Turtle Conservation
Meet the patients (below) currently housed in our turtle rehabilitation centres, after being found stranded and rescued from various locations around the Maldives. Most have been entangled in ghost nets (discarded fishing gear) that have drifted into Maldivian waters from overseas, and some are suffering from severe injuries, amputated flipper/s and ‘turtle buoyancy syndrome’ (unable to dive below the water surface, and therefore unreleasable).
This month, we successfully released both Sazna and Nilukshi back into the ocean.
Read about Shakti’s release in July, and follow her progress on our live satellite tracking map
NEW in October! Read about Barbara’s rescue, and follow her journey around the Maldives on our second interactive satellite tracking map
Sea Turtle Nest Protection
- 8 June – a Green sea turtle nest was discovered on the beach at Landaa on 8 June (near Villa 223). We erected a protective cage to prevent predation and damage. For the first 50 days of incubation, we monitored the nest weekly.
- 28 July onwards – as the hatching day approached, the nest was monitored 3 times daily (at 23:00, 03:30 and 09:30).
- 3 August – a sand depression was observed, following several days of heavy rain, but no hatchlings or tracks were seen.
- 7 August – expected day of hatching. We decided to excavate the nest to assess the situation, and found:
- 63 undeveloped eggs,
- 3 partially-developed eggs,
- 49 empty eggshells.
Despite our continuous monitoring efforts, the 49 hatchlings must have emerged several days earlier. Presumably, they successfully dug through the sand and underneath the protective cage, to head down the beach to the ocean (their tracks being erased by the rain). It’s possible that the changing weather conditions and variable sand temperature may have played a role in the high percentage of undeveloped eggs.
Sea Turtle Ocean Enclosure
- On 2 July, we reinstalled our sea turtle rehabilitation ocean enclosure.
- 25 July – Nilukshi (a juvenile Olive Ridley) transferred to the enclosure; after just 2 weeks, she was successfully diving down to retrieve food, and resting on the bottom.
- 7 August – small holes were repaired in the side net, using extra netting and cable ties.
- 11 August – Nilukshi released.
- 20 August – we cleaned the enclosure of algae, and repaired small holes in the base netting with fishing line.
Maldivian Sea Turtle Identification Program
Turtle photographs are kindly sent to us from members of the public, fellow marine biologists and dive centres 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 August, we received 15 submissions from the public to our national turtle ID project.
Our current database contains: 1263 Hawksbills, 221 Greens, 98 Olive Ridleys (4788 total sightings logged).
Spotted a turtle? Share your photos
Green turtle #CM214, from our ID database of Maldivian turtles
Nilukshi was admitted to our turtle rescue centre in April, and is pictured here enjoying a fish ‘popsicle’!
She was successfully released back into the ocean on 11 August, after 4 months of care at our turtle rescue centre
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 2020 Diary for all the latest updates.
You can see how your sponsored frame grows by viewing our photo updates every 6 months, as part of our unique Coral Frame Collection.
Photos: (1) Reefscapers coral frames at Kuda Huraa water villas.
(2) Junior Marine Savers learn the importance of corals.
