The Process of Coral Gardening
Coral gardening involves obtaining young corals, growing them in land-based nurseries, and outplanting them to damaged areas on a structure fixed to the seabed.
Widely used globally is the 'fragmentation method', which involves the break down of parent colonies into smaller pieces. This technique almost exclusively used for branching corals has shown relatively rapid expansion of local populations. The disadvantages are that fragments are genetically identical to the parent, which decreases the long term resilience of coral reefs to environmental challenges. Although this method has its merit for the recovery of fragments following storm or vessel damage, restoration efforts are needed for ensuring the genetic diversity of the damaged area.
Living Reefs Foundation is pursuing
a different and more innovative approach, and is focusing on non-branching hard coral species, relying on sexual reproduction to obtain young corals, or 'larval seeding'.
This shift in approach will lead to a more environmentally sustainable protocol, leaving natural coral colonies untouched, and contributing to genetic diversity.
This will benefit restoration efforts for both boulder and branching species, rather than the current almost exclusive focus on branching corals.
The high level of scientific expertise available at Living Reefs and BIOS make this work possible, providing new data for coral restoration, replicable to Caribbean territories.
Fragmentation Method: Bonaire
Bonaire branching coral fragmentation
Boulder coral releasing eggs
Release of eggs by boulder coral
The Coral Garden Frames
Bermuda's First Coral Gardens are pyramid-shaped, anchored to the seafloor by rebar hooks. These frames are experimental and serve to determine the best restoration methods. They can be removed and transferred to a more favourable site.
Young corals are transferred to the frames; it takes 12-18 months for corals derived from larval seeding, before they are ready for transfer.
Fragments of branching corals obtained from the seabed are planted on the garden at the same time. This provides us with valuable data on the effect of restoration on the site itself.
Maintaining, Monitoring, Evaluating
Newly planted young corals are not capable of removing sediment landing on their polyps; a team of students assists Living Reefs in cleaning the corals monthly until such time that they become self-sustaining.
Growth of corals is monitored through time-lapse photography, and scientific surveys are conducted on the surrounding reef to evaluate any change in natural recruitment.