Thank you for signing up to keep in touch with the Coral Conservation Project. Pictured above, you will find your coral frame as it was few days after construction. Your personal page will allow you to see regular updates and amazing facts about the corals and animals living on your frame. By having all the updates on one page, you will be able to track the progress of your frame and see how your contribution is benefiting the ecosystem. If you want to satisfy your curiosity even more, you can take a look at our Marine Blog Life and videos from the Marine Lab Diary or connect with us for more information.
Here is the start of a healthy coral reef relationship!
Look at this amazing visitor to your frame! These are just a few of the species that would often visit the coral frames and are extremely helpful at times when cleaning the frames. This species is called the Moon Wrasse (Thalassoma lunare) a very typical and brightly colored species of fish found in the Maldives. It belongs to the wrasse family which consists of over 600 described species that range on average around 20 cm although the Humphead and Napoleon wrasse can grow up to 2 meters! They are carnivores by nature, feeding on a wide range of small invertebrates such as crabs or snails. Many smaller wrasses follow the feeding trails of larger fish, picking up invertebrates disturbed by their passing.
As you can see from the picture, your coral frame are colonized by some little, brown and green organisms called Ascidia. The species is called Didemnum molle (also known as the green barrel sea squirt or the green reef sea-squirt.) and is very common in the Indo-Pacific area. Ascidia is a filter-feeder, feeding on suspended plankton and detritus and its green color is given by the algae living in symbiosis with them, in this way the algae is protected by the predation and the Ascidia can receive energy from its little hosts. Luckily they don’t possess any threat to the corals when they are few in numbers, however they can colonize quite quickly on the frames through asexual budding, as such they are regularly removed to minimize competition with growing corals.
Have you ever wondered how corals are eating and defending themselves … here you will see some small extensions/tentacles protruding from each of the polyp housings. They are referred to as the defensive/offensive stinging mechanisms similar to sweeper tentacles and are often linked to their feeding and defending. Inside each of the polyps are the small animals that look similar to an upside-down jellyfish with tentacles that surround the mouth part, depending on the coral species, the amount of tentacles may vary. They will move around to collect small particles floating in the water, usually plankton. These tentacles are also used for defending themselves against predators such as the coral eating snail, Drupella sp or the invasive Crown of Thorns Starfish. They also keep smaller predators such as crabs and invertebrates away. These tentacles are seldom seen, but do come out when they are feeling threatened or during feeding.
Looking at your frame, you will see that it is doing amazing and the corals are really growing well since the last update even after the heated months and some stormy weather. We have done some recent maintenance on all the frames which include cleaning them, removing the invasive algae and coral predators to maximize growth. In the upcoming post we will show you close-ups of your frame and the coral fragments, with some interesting facts and findings about those that are on your frame. After 6 months you will see a similar post showing once again the progress of your frame.
Here you will see the partial shape of the cable tie that we used to stabilize this particular fragment to the iron frame. In one month we can already see that this Acropora have started to overgrow this plastic tie and will soon be part of the skeleton forever. Plastic cable ties are a good compromise for attaching corals to the structure, since the material is cheap, resistant and the results are great, however we are looking into using different materials to improve our techniques of reducing plastics in the ocean. When this colony have reached the minimum size for spawning it will release its gametes in the water that ultimately leads to the formation of new colonies elsewhere on the reef
Your frame is the start of a new beginning for the Thudufushi House Reef! Your coral frame is part of an experimental trial. We are trying to determine if we can start a coral frame chain that will act as an artificial reef. The “frame chain” is currently located on the sandy seafloor in front of the Main Bar & Water Villa Jetty.
A few concerns we are having with this location are the shallow water, which might make the corals more prone to bleaching due to warm waters. We are also concerned about the stand and possible turbidity that might not allow enough light to penetrate for photosynthesis.
So why did we choose this spot? As we are trying to expand our coral reef and help corals take back areas they used to inhabit before the big bleaching in 2016 we need to expand frame locations past the already existing reef. Furthermore the location is easily accessible for the biologist to monitor and clean the coral frame and react to any changes quickly.
Let’s cross our fingers and hope the corals will adjust to their new location well.
Have you ever wondered why some corals are more colorful than others… That is because some corals increase the production of colourful protein pigments (such as these purple tips) when they are exposed to more intense sunlight and this colony, of a branching Acropora, is simply amazing. Scientist have found that these pink, blue and/or purple proteins act as sunscreens for the corals by removing substantial light components that might otherwise become harmful to the algae hosted in their tissue. Corals rely on these light-dependent miniature plants, the so-called zooxanthellae, since they provide a substantial amount of food. Furthermore, these tips consist of a particular polyp called an “apical polyp”. It is responsible of the growth of the particular branch. For instance, it will reproduce asexually by cloning itself, potentially an infinite number of times throughout its lifetime. Here and there, one of the “radial polyps” will differentiate becoming a new apical polyp with its distinguished purple color, driving the growth of a new branch.
We have some unfortunate news this month as we are starting to see some evidence of bleaching around the coral frames. Coral bleaching can be ascribed to warming ocean waters for extended periods of time where the symbiotic algae (Zooxanthellae) living inside the tissue coral is expelled by their host and in turn leave behind a bleaching white skeleton. This algae shares a mutualistic relationship with the corals; the coral provides shelter to the algae and in turn the algae can provide as much as 90% of the nutrients produced by photosynthesis which is used towards their growth. Corals can survive bleaching events such as this, but if they are subject to more stress or prolonged heated waters, they will surely die. Unfortunately, your frame is also showing minor signs of bleaching of around 10%. This is a rough estimate based on the amount of bleaching fragments of the entire frame. As you can see from the images, their white skeletons are not something anyone can miss, especially in the water. The degree of bleaching on your frame is luckily limited to a few fragments that show signs of surface bleaching (the areas with greatest exposure to sun’s rays) and as you can see there is some loss of algae which accounts for the pale colored corals.
Unfortunately, there is not much we can do at this stage, but wait to see whether they recover or not in the next months. Should they not recover and they are completely dead, they will be removed from the frame and replaced with new live ones. This is of course a major setback for our coral conservation project, but it is also the reality we are dealing with today.
Coral growth is a process that takes a very long time since corals invest a lot of energy in building their calcium carbonate skeleton. Stony corals (or scleractinians) are the corals primarily responsible for laying the foundations of, and building up, the reef structures. Massive reef structures are formed when each individual stony coral organism—or polyp—secretes a skeleton of calcium carbonate. Just after two months you can already appreciate how the coral have started to attach onto the steel frame. This is really good because it means that the coral is definitely still alive and growing. Let’s see how much they will grow in the following months
As you can see from your first post, we have already done the first maintenance on your frame which is to remove the additional cable ties and some cleaning of overgrowing algae. We will soon move your frame into the reef where it will form part of our latest restoration project (be sure to look out for our latest blog on this project). Some information about the fragments that we put on your frame, all of them belong to the genus Acropora which is one of the fastest growing corals and almost 149 species described. Over the next few months we will show you some close-up pictures of the fragments with some interesting facts and the creatures that now lives on your frame. After 6 months we will show you the progress of your frame in a new post.
