St. Petersburg Coastal and Marine Science Center
Coral reefs make up the most complex marine ecosystem on earth, essential to literally millions of plant and animal species. Over the past three decades, coral reefs in the western North Atlantic, including those in Virgin Islands National Park, have been damaged by diseases, storms, coral predators, high water temperatures, and a multitude of direct and indirect human activities. To date, there has been little to no recovery on damaged reefs. Diseases, storms and high seawater temperatures have played a major role. Degradation from human impacts continues to escalate simply because there are more and more people living near or dependent on the sea. A damaged coral reef cannot be restored to its original condition. True recovery of a reef could take decades to centuries, making damage prevention the priority management strategy. Nonetheless, with the increased incidence of damage and the continuing lack of recovery on Caribbean reefs, interest in rehabilitation and enhancement of reefs has heightened, specifically in transplantation of coral colonies to reefs of importance to local communities or in protected areas.
If reef enhancement or rehabilitation is to be undertaken, two questions must be answered:
This research was conducted in the nearshore waters of Virgin Islands National Park, St. John, US Virgin Islands. Storm-produced fragments of the three fastest growing species of Caribbean coral (elkhorn, staghorn and finger corals) were collected from habitats inhospitable to survival and transplanted to other reefs (Trunk and Whistling Cay). Inert nylon cable ties were used to secure the fragments to the sea bottom (dead coral). At the beginning of the project, little was known about survival and growth of small coral colonies. Sixty transplanted and 75 reference colonies were monitored for survival and growth for 12 years (1999-2011). Over 70 volunteers from Friends of Virgin Islands National Park and 5th and 6th grade classes from Pine Peace School monitored the colonies monthly (1999-2001).
|All colonies||135||12 (9%)||3 (5%)||9 (12%)|
|Elkhorn coral||75||9 (12%)||1 (3%)||8 (18%)|
|Finger coral||30||3 (10%)||2 (3%)||1 (7%)|
To reiterate, damaged and degraded reefs cannot be restored or rehabilitated to their original condition. Until the basic processes driving declines on coral reefs worldwide are understood and forcing factors such as increasing human-population pressures on marine and coastal resources are addressed, the future does not look bright for coral reefs. However, there is a place for small-scale rehabilitation efforts. For little expense and using readily available materials, local communities can effectively, albeit modestly: 1) minimize damage to intact corals by stabilizing loose fragments; 2) decrease incidence of human caused reef damage through community education; and; 3) create coral "gardens" of harvested storm-generated fragments that can then be used to mitigate direct damage to coral reefs, such as from boat groundings.
Garrison, V.H., Ward, G. 2012. Transplantation of storm-generated coral fragments for coral conservation: A successful method but not the solution. Revista Biologia Tropical (Int. J. Trop. Biol) 60 (Suppl. 1): 59-70. [transplantation-storm-generated-coral.pdf (720 KB PDF)]
Garrison, V., Ward, G. 2008. Storm-generated coral fragments – A viable source of transplants for reef rehabilitation. Biological Conservation 141: 3089-3100. [http://dx.doi.org/10.1016/j.biocon.2008.09.020]
VH Garrison (US Geological Survey, 600 Fourth St S, St. Petersburg, FL 33701; 727 803-8747 ext. 3061; email@example.com)