Hello! I’m Haleigh Collins, an Environmental Educator at Forfar Field Station in Blanket Sound, Andros, Bahamas. Run by the nonprofit International Field Studies, Environmental Educators at Forfar spend most of our days teaching middle school through college-aged students about marine science, island ecology, and the local Bahamian culture. When not teaching about the importance of conserving the ocean and its inhabitants, we are doing all we can to protect and rehabilitate it. We are responsible for maintaining the Forfar Field Station Coral Nursery where we grow, or propagate, branching corals like staghorn, elkhorn, fused staghorn, and finger corals. Three lines hold 70 fragments of growing corals that are continually trimmed and planted on the surrounding barrier reef.
Forfar Educators Haleigh Collins, Tayt Stafford & Aaron John mix two-part marine epoxy which is used to fix corals back onto the substrate underwater. Image by Hayley-Jo Carr
Propagating coral helps diversify coral reefs. By growing coral in a safe environment, it ensures corals can grow fast in an ideal setting. Coral nurseries are set up to hang corals in the water column, instead of being attached to the substrate. As each small fragment branches into large corals, it is taken to a reef and attached using a two-part marine epoxy. Once the coral completely anchors itself to the substrate, it is able to grow, reproduce, and diversify the coral populations in its area.
Forfar Field Station Line Nursery before corals were ‘pruned’ for planting. Image by Hayley-Jo Carr
Reef Rescue Diver Aaron John assisting in coral nursery maintenance. Image by Hayley-Jo Carr
Aaron John swims cut corals up to the boat to move to the outplant site
When you think of a coral nursey, lines of hanging coral fragments is not what comes to mind. It seems counter-productive for these corals to hang from fishing line in the middle of the water column. They need to attach to something to grow, right? Wrong.
By growing corals on these hanging lines, it virtually cuts out all predators or threats these corals would encounter if they were attached to the substrate. They do not have to compete for space, and since they are not touching it helps limit any disease spreading through the colony. It also makes caring for the corals much easier.
Most coral nurseries are set up as “tree” nurseries. PVC pipe frames shaped like Christmas trees are attached to an anchor and a buoy that keeps the frame off of the ground yet submerged. Most nurseries would have multiple trees in one area.
The Forfar nursery is set up a little differently as it was one of the first ones established with the help of the Perry Institute for Marine Science in 2015.
- Two thick ropes are attached to anchors about 30 feet apart.
- The tops of those ropes are attached to floating buoys to keep them standing upright.
- Strong fishing line is attached to both ropes horizontally in three rows.
- From the three main fishing lines, smaller segments of lines are suspended vertically about a foot apart.
- A noose-like closure secures a coral fragment to each vertical line.
Overall, this style of nursery can hold around 70 growing coral pieces in one area.
Alex Borreil carefully moves corals from the cooler into a crate for divers to take down to the reef to be planted.
A nursery grown fragment of Acropora cervicornis is planted back onto the reef at Strings Quartet. (Image by Hayley-Jo Carr)
Reef Rescue Diver Aaron John planting corals back on the reef. (Image by Hayley-Jo Carr).
On a monthly basis, Forfar Field Station staff go scuba diving at the nursery site to clean and maintain the nursery lines and growing corals. Scrub brushes and gloves are used to clear any algae growth on the fishing lines, ropes, and buoys. Pliers and metal spackle knives are used to scrape away hard growth and break off fire coral that try to encroach on the young corals. Once all areas of the nursery are cleaned, staff check on each piece of coral. If a piece of coral has died or fallen off the line, a new fragment is taken from a larger growing piece and reattached in the empty space.
Currently, the Forfar nursery has 69 total growing corals; 56 are Acropora cervicornis (staghorn), 11 are Acropora palmata (elkhorn), and 2 are Acropora prolifera (fused staghorn). Of the three species, Acropora cervicornis and Acropora palmata are critically endangered, thus most of the growing space is devoted to those species.
Over a couple of days 121 nursery reared coral fragments were planted back onto a nearby coral reef. Images by Hayley-Jo Carr
After growing in this safe space for a year or more, depending on the species, the large, healthy corals are moved to their forever homes. Staff use large pruning shears to cut sections from the main branches of each coral. The coral base stays attached to the nursery line and new growth begins almost immediately. The cut fragments are placed into baskets by species, counted, and then brought to the surface of the ocean. The fragments are transferred into a cooler of fresh sea water and transported to the outplanting site.
Strings Quartet, the current outplanting site, is part of the barrier reef on Andros. It is the world’s third largest fringing barrier reef. Branching corals can withstand the constant rolling waves that crash over of the shallow barrier reef, so this is an ideal location for these corals to be outplanted.
The new coral fragments are attached to cleaned substrate away from any other corals or competitors using a two-part marine epoxy. The staff outplant these corals on the leeward side of the reef, where there is less chance of them getting broken off by large wave or storm action. Once the marine epoxy hardens, the corals do the rest of the work. They grow and attach over the marine epoxy to stabilize themselves further to the substrate. As they grow larger, the corals are able to reproduce and repopulate the local reef. On our last outplanting trip, Forfar Field Station staff was able to successfully attach 121 coral fragments.
Tayt Stafford plants corals to help regenerate local reefs – there is still hope. Image by Hayley-Jo Carr
Sadly, we will continue to see large coral bleaching events that last longer, and corals will need more time to bounce back to health. Coral reefs are imperative to ocean health and marine life diversity so the impact of coral bleaching will have profound negative effects on not only marine life but the economies relying on them as well. With the current rate at which the ocean temperatures are rising, these reefs will continue to die. So, why even try to repopulate the reefs? By diversifying the reefs with corals from a variety of genotypes and species, we hope to aid reef survival by increasing the mix of genetics so that corals can be more resilient to our changing ocean. Outplanting helps these local reefs stay healthy by introducing young corals into an otherwise old reef that is on the decline.
It may sound bleak, but the future of corals is still bright. By learning about coral reefs and what you can do to aid in their continued existence, you can be a part of the solution. You can help preserve and protect these beautiful creatures. Make conscious choices with your sunscreen, beauty products, clothing and daily habits. Choose to eat environmentally sound fish and support organizations that do everything they can to protect these waters.
If you would like to do more, take a training course and become a REEF Rescue volunteer. Starting conversations with peers to bring attention to this issue can also aid in the development of solutions and improved coral health. You too can be a part of the movement that saves our reefs.
Congrats to Haleigh Collins and Aaron John on becoming PADI Reef Rescue Divers during this recent trip with PIMS Training Director Hayley-Jo Carr. We would like to thank all the team members at Forfar Field Station for their commitment to protecting our coral reefs and a huge thank you for assisting in maintaining the coral nursery and with