Boulder Coral Nursery Development
When CRF™ was founded in 2007, we focused our efforts growing branching corals in our nurseries, specifically elkhorn and staghorn coral, because they were the dominant reef building species throughout Florida’s Coral Reef and had seen a 97% decline in 30 years.
Now in our 14th year of operation and growth, we care for 11 species of coral native to Florida’s Coral Reef! Since each species of coral grows in different ways, it takes some time for us to learn how ©Alex Neufeld/Coral Restoration Foundation™ to best propagate them.
Branching corals grow best on our original Coral Tree™ where each coral fragment is suspended in the water column, allowing the coral to grow in every direction with nutrients to flowing over the entire colony. Boulder corals are a mounding species. They grow upwards from a singular base. Therefore they needed to be housed on a different tree design.
Left: Boulder coral trees used for long term care in our gene bank. Center: Original boulder coral tree with trays. Right: Current boulder coral tree with trays. ©Coral Restoration Foundation
“Our boulder coral trees are just one example of how CRF™ constantly improves to raise as much coral as possible! I love seeing how our methodologies and techniques transform over time" said Chris Reynolds, CRF™ Dive Program Intern.
The newest boulder Coral Tree™ design is the 3rd iteration and most successful.
We have gone through several iterations of the boulder tree to find the best version. The first looked very similar to our branching coral design; plaques with boulder corals attached were hung from branches with monofilament line. We upgraded to trays and have seen more success with this design. Last year, we began designing and implementing our newest boulder coral tree, and we think we’ve cracked the code! This new tree design is stable, strong, and holds ample boulder fragments!
Speaking of boulder coral improvements, we have propagated enough boulder star coral (Orbicella annularis) and mountainous star coral (Orbicella faveolata) in our nursery that we can now regularly return them to the reef! Both of these species are important reef-building corals that provide solid stabilizing structure as they grow.
A curious boxfish nibbles on algae next to recently outplanted boulder coral plugs. ©Alex Neufeld/Coral Restoration Foundation™
When we first began planting these species, we used a very similar approach to our branching corals where we clear algae away from old reef then used epoxy to secure the coral fragment to the limestone. However, boulder corals have mounding growth patterns and form a sphere as they get larger.
New boulder coral domes allow outplants to grow in a more natural shape. ©Daniel Burdeno/Coral Restoration Foundation™
Coral Restoration Foundation™ in collaboration with the Coral Restoration Consortium, Secore, Ocean Reef Alliance, and Reef Cells, began thinking of ways that we could help these corals grow more naturally – and thus the boulder dome was born! We created concrete domes with holes in them to fit small plugs holding boulder coral fragments.
The entire base of the dome is secured to the reef and filled with plugs of boulder coral. As the fragments of coral grow, they fuse together to form one large boulder coral, mimicking what they look like in the wild!
HORSESHOE REEF GETS NEW CORAL
This year, we have returned more corals than ever to Horseshoe Reef in Key Largo as part of the Mission:Iconic Reefs coral restoration plan! Horseshoe Reef is famous in the upper keys for being home to the largest remaining stand of natural elkhorn coral! It is beautiful and full of marine life – one of our boat captains even saw a hammerhead shark swimming by recently when mooring the boat!
Freshly restored coral on cleared substrate at Horseshoe Reef. ©Charis Peterson/Coral Restoration Foundation™
In March, our team returned 402 staghorn corals here and we plan to do more in the year to come. Through surge and high waves, every fragment of staghorn coral was carefully placed and affixed to cleared substrate. We can’t wait to visit this site again soon with our Science Team to observe the growth and success of our new corals!
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"Bringing It Back" Editorial Intern
Bailey grew up on a lake in North Carolina, and has felt connected to the water for as long as she can remember. When she was 10 years old, she got SCUBA certified and started taking annual diving trips to Florida where she saw first-hand the decline of coral reefs in the Keys. Knowing that she wanted to make a career in marine conservation, she joined an Operation Wallacea expedition to Greece where she learned field work skills.
Bailey graduated from the University of North Carolina at Chapel Hill in 2019 with a major in Biology and minors in Chemistry and Marine Science. During her four years there, she worked as a research assistant investigating how the calcium carbonate skeleton of corals are affected by ocean warming and acidification. Most recently, she worked as a summer camp educator at the Discovery Place Nature Museum in North Carolina where she taught students about the natural environment and how to protect it. Bailey is so excited for the opportunity to work with Coral Restoration Foundation™ towards its mission of restoring coral reefs