Monday, March 16, 2009

Transplanting Corals - Restoring a Reef

BREAM Scientist Dr. Thad Murdoch prepares finger corals
for attachment on the reef being restored.

BREAM and the Bermuda Government Department of Conservation Services have been working together to transplant corals from an old sunken barge at Dockyard to restore a nearby coral reef damaged by a cruise ship grounding in 2006.

The 100-yr old wreck of one of the barges used to build the King's Wharf at Dockyard is located next to the new cruise ship pier. An RG article about the wreck can be read here: link.

While the wreck is deep enough to be left in place, except for a single spindle, or mast, the corals on the wreck are likely to be damaged by the currents generated by the ships' propellors and by the silt they kick up each time the ships approach or leave the pier.

For this reason we felt it best to remove the corals. The most suitable place to transplant the corals is the nearby reef that was struck by the Nordic Crown in 2006 [link].

With the use of Conservation Services research vessel the R.V. Calamus, team members Dr. Philippe Rouja (Custodian of Wrecks), Anson Nash and Mandy Shailer from Conservation Services, Dr. Thad Murdoch, Jessie Hallett and Robert Fisher from BREAM, Bermuda Zoological Society, and Jeff Porter, Aquarist at BAMZ/BZS moved corals on Thursday and Friday (12,13 March), and are going to finish the task after the 18th March, when weather clears.

BREAM research assistant Jessie Hallett
removes a coral from the mast of the wreck.

To move the corals, Rouja, Fisher, Hallett and Murdoch dived the wreck on SCUBA. Hallett and Murdoch carefully detached corals from the wreck, either with a hammer and chisel or by hand. This can be done because the bottom side of the corals is dead skeleton, not live tissue. While Rouja documented the process on video and still cameras, Hallett and Murdoch passed the corals to Fisher, who placed them in crates attached to ropes and pulleys and then winched the corals up to the Calamus above them. Shailer, Porter and Nash then carefully removed the corals and placed them in large seawater-filled containers to keep them wet during the removal phase.

BREAM volunteer Robert Fisher raises
a crate filled with corals to the boat above.


Once all containers were filled the team moved the Calamus to the ship grounding reef location. After anchoring over the location we lowered the containers of corals to the sea floor and transported the bins to the restoration site. Corals were carefully placed along the scarred reef in preparation for attachment.

Once all corals were in place Hallet, Rouja, Murdoch and Fisher then cemented the bases of each coral to the bare rock - being carefull to give each coral space to grow.

A transplanted finger coral, held in place
by a special blend of cement.


Once the transplantation process is finished the BREAM and DCS team will monitor the transplanted corals to see how well they coped with the move.

The close collaborative relationship between the Department of Conservation Services and the BREAM team at the Bermuda Zoological Society was crucial in this conservation effort. We were able to both save corals from damage and return corals to an area in need of restoration - two wins for Bermuda's marine environment!