Good News of Coral Rehabilitation
Written by Juli Cole, 20 June 2024.
As we all know, the world is experiencing its 4th wave of global coral bleaching. We are all shocked and really sad to see what has been happening to our corals for the past many months. Corals rely on tiny algae called zooxanthellae to survive. However, situations such as an increase in temperature and high amount of pollution, causes a stressful condition for these corals. This is when corals turn white and bleaching happens. This is a sad view from our recent trip to Perhentian but it is reality at the moment. If we do not act quickly on these stressors, we will lose these corals for good. Juli saw this painful situation and did more research into it. Fret not, there are measures being taken and parties getting involved in the rehabilitation of corals. Read more on what is being done in Juli’s write up below. – Editors note.
It is a sad, sad fact that many of our loved coral reefs are dying. We don’t see this reflected in the fun pictures and videos we post of amazing dive trips and fantastic ocean creatures we find – if you are like me, we are highly aware of the problem but either don’t know what to do about it, think we don’t have the time to do anything about it, or we are still just trying to not use up a tank of air in 20 minutes!
I can tell you; I have watched some depressing documentaries. The worst was when the researcher burst into tears after documenting a reef section that failed in months– and this was a well-educated scientific guy with a huge investment into his project. Among all the sad tales however, there is much successful work being done to restore the reefs and work to bring them to life. I thought to share these with you.
But first I need to talk about why reefs fail, you know, the depressing part – sorry! First and foremost is global warming. Most coral can only live in a narrow band of water temperatures that can only vary by a few degrees – which may sound alarming but remember this is the ocean which typically stays at constant temperatures with a few odd occurrences like in a El Nino/El Nina year. This is the part that overwhelms me because I think the atmosphere is huge and I am one small person in it and how can my walking instead of driving make any impact on global warming? We are seeing across the world radical changes in government thinking and focus to cleaner energy sources and movement away from dependence on fossil fuels. You may think “not where I live” but I promise you it is happening! And if we each do our own little parts to live in a more sustainable manner, it does add up.
Another contributor to reef failure is of course human activity. Destructive fishing practices, irresponsible tourism operators – “loving” the reefs to death, poor municipal practices and oversight, pollution – these are things we can change through the choices we make when we travel to other countries as well as in our own country (do your research on that dive center – there may be a reason they are cheap!), speaking out and supporting initiatives that seek to effect positive changes. One person on their own cannot effect much change, but many people taking to social media can.
On the positive side. There are many NGO’s, non-profits and government agencies around the world directly working on projects or sponsoring others in their efforts. At the basic level, the process is simple. Coral can reproduce asexually through either budding where they produce polyps (kind of like a little seed) that drops to the substrate and begins forming a new coral colony. Or new colonies can be grown from a piece of broken off coral. Most methods then are focused on either creating a stratum for a new colony to grow on or create a nursery where coral can be grown then transplanted to create a new reef.
However, as any observant diver knows, a coral reef is a complex ecosystem, supporting life down to the microscopic level. So just planting a bunch of Staghorn coral that is easy to reproduce will not do the job. This creates monocultures of genetically identical colonies. Coral also reproduces sexually which ensures genetic diversity which in turn creates healthy colonies able to better adapt to stress. Additionally, there are many species of rarer coral and non-fish organisms that are not easily reproduced in a nursery. So, because of these factors and many others like it that drive scientists mad in the middle of the night, inventive individuals have come up with some really interesting methods to overcome the hurtles.
Biorock is a creative product – it was invented in 1976 by Wolf Hilbertz, an architect who desired to produce natural building material in the sea. It is created by passing an electric current through electrodes underwater causing minerals such as calcium to dissolve out of the sea water. They are strongly electrically attracted to the activated cathode and will accrete in a thick layer, forming limestone. This creates a new stratum for the coral to attach to, either through natural methods or planted. This process has been successfully used to create more than 500 new reefs in over 40 countries, with a majority in Indonesia. (globalcoral.org/biorock-coral-reef-marine-habitat-restoration/)
Another interesting experiment is through the use of acoustics: by playing sounds of a healthy reef – the crackles, pops, buzzing noises we hear as divers and much more we cannot hear – researchers found they could attract and entice coral larvae to failing and degraded reefs. These reefs tend to have less diversity of inhabitants and thus have a quieter and less rich soundscape. So just like youth, they want to be where the clubs are and not in quiet suburbia! The larvae are a result of sexual reproduction and are the only time in the coral’s lifecycle it is mobile. Though the article I read did not address this, I would suspect that the larvae would create genetic and species diversity, leading to a healthier stronger reef. (whoi.edu/press-room/news-release/sonic-youth-healthy-reef-sounds-increase-coral-settlement)
Other ingenious ideas include creating artificial clouds to shade reefs. The principle actually comes from the negative phenomenon of emissions mixing with clouds and the confined particulates reflecting sunlight back to the upper atmosphere, creating a cooling effect. Rather than using fossil fuel emissions however, sea salt is delivered into marine clouds, reducing the size of the water droplets, increasing condensation in the cloud and thus creating more reflectivity. It is the same principle used on land in cloud seeding to create rainfall. However, the desired effect in the oceans is to create larger clouds reflecting more sunlight and thus cooling the reefs. They call it “Cloud Brightening”. (wikipedia.org/wiki/Marine_cloud_brightening)
As a last desperate measure, coral species, especially rare and endangered, are being collected and stored, using cryogenic chambers, in an effort to protect and preserve what we now have. Using the stored sperm from the coral, scientists can also migrate species that are isolated due to population decline. For instance, in 2021 it was announced that a colony of Elkhorn coral, a declining rare Caribbean coral, was successfully grown from harvested sperm in The Florida Aquarium, an aquatic zoo and institution in Tampa, Florida, USA.
Much of the efforts for coral recolonization however are through manual efforts: recolonizing failing reefs. This is a long and sometimes slow effort in collecting, growing and planting new colonies. This requires volunteer divers to help with the work. We actually have several in our region. I had wanted to write this article from the perspective of having volunteered with one, but I am still healing and land bound at the moment. So, I can’t tell you firsthand how this work. There are some organizations that are “pay for the experience” such as Bubbles in Perhentian Besar, Malaysia or there is an awesome sounding place in Fiji on its own private island. I have listed below some of the ones locally.
Whether you want to volunteer or want to donate funds (everyone welcomes those!) or don’t want to do either, it is still up to us to be responsible as much as we can for the health of our oceans. It can range from simple picking up rubbish you spy on a dive, doing your homework before diving – make sure all the players are ecologically responsible from the boat operator to the hotel proprietor, using products especially on the islands that are marine friendly, and speaking out in defense of our reefs. I came across a friend who was given this expensive gift of frozen shark fins – she did not want it but did not know what to do with it, especially since it was costly. I am happy to report everyone was telling her off for having it – my poor friend! I was glad to see that the word is spreading.
Here are some websites for local agencies involved with coral restoration work. There are also many international organizations.
- https://www.reefcheck.org.my
- https://www.coralku.org/action – they are working out of Pulau Lang Tengah, a little island between Perhentian and Redang.
- https://www.tengahislandconservation.org/ – this group has a variety of projects marine, and land based as well as turtle preservation.
- https://tracc.org/ – this group is based on Pom Pom Island, Semporna, Sabah.
Other than these, if you want to be a part of environment educational programs, Project AWARE is a good start. Flow offers these programs so just WhatsApp or email and we’ll definitely be more than happy to share details.