People sometimes wonder what exactly does a coral management program do.
Maybe protect corals in some ambiguous way? Let us take a moment and explain what we do and how we do it.
One of our primary activities is creating and managing a sustainable quantity of coral for our volunteers to return to our local reefs. Coral populations have suffered heavy losses from disease outbreak, warming water temperatures and storm damage during the last twenty years. Our program responsibly harvests native corals and then propagates them by asexual fragmentation. This method takes existing fragments of live coral and breaks it into small colonies that are protected and able to heal and then grow healthy and large. In this manner, we can take a small amount of coral fragments and over the course of a single year create an abundance of large colonies suitable to return to our local reefs.
Everything starts with our volunteers. As of May 2019, we have trained over 200 Coral restoration divers and issued PADI certifications to every one. These skilled volunteers learn about the issues facing corals worldwide and right here at home in the Cayman Islands. We teach them how to interact with our corals and every one of our volunteers spends time underwater with our project corals.
Combining our trained volunteers with our newly grown coral colonies, we must then strive to return these corals back to our local reefs. However, this is not as simple as you might expect. Placing a live coral colony back onto our local reefs is an important step toward proper reef management, but it is not the true end goal. Instead we had to sit down and do some serious thinking about what problems we sought to correct and how to truly reinvigorate our local reefs.
Here we can see some of the problem. Live coral covered with sand and struggling to survive. Branches covered in algae and little nearby coral cover to protect these delicate animals. It is easy to think of the seafloor as an unchanging sprawl, but the reality is very different. The sea is a dynamic place and every coral reef, sandy beach or tropical lagoon is a unique biome with a diverse and special ecosystem. Each coral that we work with has been in our care for up to two years and it is our responsibility to learn to properly understand the reef ecosystem so that we can best manage our corals.
We seek out sites underwater that are able to offer our corals the best chance to survive. Predators come in many forms and it falls to us to learn what they are and how to avoid them. Likewise, we have to observe and understand what is happening underwater as time moves forward. A storm, rising water temperatures or even human impacts can radically alter the survival rate for corals.
Discovering a suitable location for our corals and placing them safely allow the corals the best chance for survival. But our program is not about simply surviving. Our corals must reproduce every year and add back to the genetic diversity that has been severely reduced over the previous twenty years. Our corals must prosper in their new homes and every Summer when they release their spawning material, adding both abundance and the diversity that has been lost over time.
And at this point we had to stop and take a long look at what long term goal we were truly pursuing. Relocating coral to nearby reefs feels good, but is it a responsible use of the limited material we are entrusted with? Placing coral back onto the reef is “what we all do”. But why is this? Diseases and predators prosper on the reef and turbulent damage from storms can easily destroy years of effort overnight. Moreover, is placing coral back onto the reef anything different that decorating the reef? How does that newly placed coral contribute to the local reef community?
So we stopped transplanting corals back to the reef. It sounds backwards, but our nursery structures are established as fertile sources with considerable impacts on nearby reefs. Our nursery sites also allow us to control the genetics being introduced to an area. The nursery structures have proven safe against storms, bleaching, disease and predators. Our corals have one task. Spawning every year. Placing them on the reef was an artifact leftover from previous concepts. Creating spawning nurseries spread evenly around our island allows us to cover vast areas with minimal coral and effort.
The best part of our concept is that every new coral settling onto the reef is genetically unique. Every red dot added to our map indicates another new genotype of coral. Diversity is the key to resisting future disease outbreaks and to restoring stability in local coral populations.
As our corals prosper and spawn every Summer, they must also disperse their young across a nearby section of reef. Every red dot shown is a single coral colony mapped in September 2018. Every circle represents a large colony spread across several feet in each direction. This is the result of our nursery corals spawning in 2017. Of the corals identified, all existed below 28 foot of water and the vast majority settled in a cone shaped area within 400 meters of the nursery structure. Additional years will hopefully bring even greater abundance, but the truly remarkable thing here is that corals are spread to both the shallow mini reef wall between 30 and 50 ft deep, and the deeper main reef wall starting at 70 foot that drops down into an amazing 1000 ft or more vertical drop. Our corals from this single year of spawning have settled on the deep wall and begun to spread down as far as 100 ft. In these deep waters, our corals can survive the rising water temperatures we face today and into the future.
So take a minute to look over what we are doing. Maybe send us a message or even visit us. I can not do this by myself. Your help is surely needed.