Fish Lab & Marine Aquaria
We recently introduced some new coral species into Aquarium One, including Favites, Favia, and a Goniopora Herpolitha limax (mushroom coral).
Our regenerating starfish (Linckia laevigata) is growing well, adding 4mm in length (~20%) in the last 28 days, and the regenerated arms are now 24-30% the size of the original arm. However, the longest arm has actually shrunk in size (69mm down to 63mm) possibly due to insufficient nutrition.
In our large marine aquarium, we have been monitoring 12 species of hard corals and 6 species of soft corals during 2018, plus two extra-small coral frames with Acropora and Echinopora fragments. Currently, three species of hard corals are in “intermediate health” with the remainder classified as “good”; they are all free from disease, bleaching and necrosis.
December was another good month for Clownfish breeding, with 3 batches of Clark’s and 1 batch of Maldivian Clownfish successfully reared.
We have finished the year with a record 723 Clownfish reared in our laboratory, on the way to our long-term goal to produce 100 fish per month. We hope to start looking for prospective local buyers or even apply for an export licence.
Our improved success has come largely from the plankton S-presso enrichment (newly available in 2018), the frozen Mysis (zooplankton) food, the water quality, and of course there’s been a lot of care and love from Aku and Carla, our aquaculture experts. 😊
Clownfish Release Programme
During 2018, we attempted several Clownfish releases with the help of our Four Seasons apprentices during their Marine Biology training. In two years, 92 clownfish were released onto the House Reef, into 26 anemones (6 created from bisection, 19 relocated, 1 in situ). The re-introduction of Clownfish was considered successful if the fish and the anemone survived more than 4 months without a protective cage and without leaving the site.
Of the 12 release experiments, only one showed a good level of success, by using a wild reef anemone for the introduction of our lab reared juvenile Clownfish (3cm long). The fish survived and grew in size over several months, but the limit of this method is finding the wild inhabited anemones living on the reef. In one of our other experiments, a hand-bisected anemone lost the Clownfish juveniles, but continues to grow more than one year on, and is now naturally recruiting other damsel and anemonefish.
Live food production
During 2018, we have produced 11,000L of microalgae, 5000L of adult Artemii and 580L of Rotifers.
The graphs below represent statistics for 2018, including production of live foods and total lab-reared Clownfish (compared to other years).
AC = Amphiprion clarkii = Clark’s anemonefish or “Yellowtail clownfish”.
AN = Amphiprion nigripes = Maldivian anemonefish or “Blackfooted clownfish”.
Below: Clownfish eggs developing over several days after being laid.
Maldivian Sea Turtle Conservation
Turtle Nests at Landaa Giraavaru
Our remaining nest on the staff beach (at V200) was expected to hatch between December 5-10. With no signs of activity by 8 December, we carefully excavated the nest to find 61 hatchlings struggling to emerge, which were immediately released to make their own way into the sea. Additionally, remaining in the nest were 4 unfertilised eggs, 1 underdeveloped egg and 55 empty egg shells, left behind by hatchlings that had successfully emerged.
In total during 2018, we had 9 Green turtle nests laid on Landaa Giraavaru, and recorded 292 hatchlings.
Maldivian Sea Turtle Identification Programme
During December, we received 80 submissions to our Maldivian Sea Turtle ID project, resulting in the positive identification of 9 new Hawksbill individuals, plus resightings for 2 Greens and 37 Hawksbills. Resightings are important as they allow us to keep track of location and health status of individuals over the years.
During the whole of 2018, we added 157 newly identified/named individuals to our database, and confirmed the resightings of a further 193 turtles. Our database totals are now 1,119 Hawksbills and 187 Greens.
We have now transferred all the Green turtle individuals and data into our new i3s database (and will soon be starting on the Hawksbills). Now we can enter new submissions more quickly, directly into the software without any manual searching and ensuring there are no duplicates.
Have you spotted a turtle ? Send us your photos !
A big THANK YOU to all our contributors. 🙂
This is ‘Debra’ CM0142 – the most sighted Green turtle in our database, with 9 sightings between 2016 and 2018 in Feydhoo Caves, North Male atoll.
Below, children learn about caring for injured turtles as part of our ‘Junior Marine Savers’ activities at Kuda Huraa.
Further News & Updates
Looking for details of our coral propagation programme ? Head over to our Reefscapers Diary for all the latest updates to our coral frame project.
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.
You might also be interested in our Dolphin ID Project during 2018, and our new Sea Turtle Enclosure out in the lagoon at Landaa Giraavaru.