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Capturing Wild Corals Building Sustainable Resilience on Coral Reefs

The Power of Small

Global environmental degradation can seem like an insurmountable obstacle for individuals and conservation organizations alike. There are a lot of ecosystems that are in dire need of protection and restoration, and limited funds to achieve large-scale goals. Often, we forget that big changes and movements can be sparked by small events and processes. Corals are the perfect example of how something that starts small can scale up over time to have regional effects. At IntelliReefs, we believe that every home we create for the ocean's homeless creates a ripple effect that can be felt throughout an ecosystem.

By letting nature take the lead, we can learn from animals like corals, and not get discouraged and overwhelmed with the global task of restoring our reefs.

Up-close Acropora sp. coral polyp.

Tropical reefs up to thousands of kilometres long are built from small, colonial animals - corals. Coral species that build reefs are often called "hard corals" or "scleractinian corals", and function as ecosystem engineers underwater; this means they build physical habitat for themselves and other animals to live in. Corals are an excellent example of how something small can have a very large ecological effect over time.

Island with surrounding reef on the Great Barrier Reef, Australia.

Coral reefs are highly complex, living structures comprised of many colonies of corals. These colonies are made up of many tiny individual animals that grow together, called coral polyps. Over hundreds of years, these colonies deposit massive reefs underwater, which humans rely on for food, storm protection, and tourism.

Each polyp has a mouth surrounded by stinging tentacles that immobilize planktonic prey and bring them to their mouths. Many coral species are also photosynthetic, and have tiny microalgae living in their tissues. The algae convert sunlight into nutrients, which are then delivered to the corals.

As coral colonies grow, they deposit a strong calcium carbonate skeleton. Over time, these skeletons build up massive reef structures that can span for kilometres and house thousands of species.

Why Corals Love IntelliReefs

Corals reproduce by either broadcasting or brooding their gametes (eggs and sperm). Broadcasting species expel their reproductive cells into the air to come into contact with their "other half" from potential mates. Brooders, by contrast, draw sperm into their polyps to fertilize their eggs and develop them internally for a period before they are ready for release. In either scenario, the end result is that baby corals (termed "larvae") spend the first week or so of their lives at the mercy of ocean currents and predators in the water column.

A Staghorn coral spawning event.

After they have matured sufficiently either inside the parent colony or on their own in the ocean, coral larvae have undergone enough of development to have developed keen senses and even little motile appendages called "cilia" that will allow them to choose and navigate towards an appropriate home; they are now termed "planula larvae". Planula need to settle on a hard substrate in order to properly attach themselves and metamorphose into the next life stage - an adult colony. They can sense light, water density, temperature, sound, and even chemical signatures in the water that guide them towards a healthy reef.

One of the indicators for healthy reef substrate is the presence of crustose coralline algae, or CCA. As a calcifying red algae, CCA contributes to reef development by binding carbonate sediments and helping to cement and build reef substrates. Perhaps more interesting still, CCA also facilitates the settlement of coral larvae. Corals can sense a reef with healthy CCA growth, and the chemical signatures that it gives off help trigger coral metamorphosis. On unhealthy reefs, often the hard substrate is preempted by fouling animals and large, fleshy algae that prevents CCA and corals from settling.

Diverse marine growth and crustose coralline algae (CCA) on Oceanite after 14 months.

IntelliReefs are designed to attract calcifying organisms, such as CCA and wild corals, from the water column and provide a substrate that enables quick and resilient growth. Our IntelliReefs coral habitats are cast from a unique, proprietary mineral mixture called "Oceanite". Oceanite is a complex matrix of minerals that mimic the natural substrate on a coral reef. The mixtures have been developed over 20 years of rigorous nanotechnology research and testing for biodiverse animal growth and immediate integration within local ecosystems.

Coral recruit after 14 months on Caribbean IntelliReefs.

IntelliReefs are capturing wild corals and giving them the tools to recover on degraded reefs.

After only 14 months of deployment, scientists found healthy, wild coral spawn settled and growing on IntelliReefs deployed near natural reefs in the Caribbean. Oceanite has a complex matrix of pores that increase the surface area for animals to settle and allow for small animals like new coral recruits to survive predators in the early stages of life. Each Oceanite mix design can be fine-tuned to target species-, function-, or site-specific conservation goals. It is composed of proprietary marine mineral matrices that include high-grade limestone, aragonite, and diverse pozzolanic (calcium-binding) components at the nano-scale to attract and support marine life.

Nearly 100% coral cover on a healthy reef in India's Andaman Islands.

Restoration efforts that maximize the efficiency and speed of these small scale processes have great conservation potential. IntelliReefs not only curates a healthy coral community quickly and sustainably, but can also be cast into custom, large-scale habitats. These local changes can create a global impact if we act quickly and use the best restoration technology at our disposal. It has been shown that when local environmental stressors are reduced, reef ecosystems are able to bounce back from global pressures more easily (Smith et al. 2016). By using nanotechnology to enhance and streamline these local processes further, we are simply giving nature back the tools to heal herself.

“Our findings suggest that in the absence of local human impacts, coral reef communities appear to be more resistant or resilient to global change than those with local human populations,” says Dr. Jennifer Smith. “This offers a new incentive for local conservation efforts on populated islands.” (Smith et al. 2016)
Close-up coral polyp under UV light.

References and Photo credits:

  • Title image by Shaun Miller / Coral Reef Image Bank.
  • Up-close Acropora sp. coral polyp by Jayne Jenkins / Coral Reef Image Bank.
  • Island with surrounding reef on the Great Barrier Reef, Australia by Katarina Katopis / Coral Reef Image Bank.
  • Close-up coral polyp under UV light by Ramona Osche / Coral Reef Image Bank.
  • A Staghorn coral spawning event by Jayne Jenkins / Coral Reef Image Bank.
  • Coral recruit after 14 months on Caribbean IntelliReefs by Ian Kellet / IntelliReefs.
  • Diverse marine growth and crustose coralline algae (CCA) on Oceanite after 14 months by Ian Kellet / IntelliReefs.
  • Nearly 100% coral cover on a healthy reef in India's Andaman Islands by Umeet Mistry / Coral Reef Image Bank.
  • Close-up coral polyp under UV light by Ramona Osche / Coral Reef Image Bank.
  • Smith et al. 2016. Re-evaluating the health of coral reef communities: baselines and evidence for human impacts across the central Pacific. Proceedings of the Royal Society B.
Created By
Emily Higgins
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