Oculina varicosa is a slow–growing, delicate, and branchlike coral that is often associated with high biodiversity and whose thickets provide ideal spawning sites for numerous species of reef–dwelling fish, including economically important species such as groupers and snappers. Otherwise known as the ivory tree coral, Oculina varicosa, occurs in depths of several meters to greater than 100 meters. Unlike Oculina colonies found at shallow depths, which are relatively small with stout, club–like branches, deepwater colonies may grow up to several meters in diameter and clustered in a thicket–like habitat. Based on average growth rates, some deepwater Oculina reefs are thought to be at least 1,526 years old. In depths of 50 meters or greater Oculina varicosa typically grows on limestone pinnacles. In addition, deepwater Oculina lacks zooxanthellae, the symbiotic algae that provide corals with their color and part of their nutrition; it is therefore white at these depths and relies solely on free swimming food. Oculina reefs typically occur in an upwelling region on the shelf edge. Scientific studies have shown a very high diversity of invertebrates, with hundreds of species represented in the interstices of the Oculina coral heads. Other studies showed that highly prized species of grouper, gag and scamp, form large spawning aggregations in Oculina habitat in February and March.

Distribution in the South Atlantic

In the South Atlantic, Oculina reefs are distributed along the continental shelf with concentrations occurring off the east–central coast of Florida. Shelf–edge prominences, or limestone “pinnacles,” lie near the 80–meter depth contour off east–central Florida and extend tens of meters above the surrounding sea floor. This area, called the Oculina Bank, is located approximately 15 miles offshore Fort Pierce. The Oculina Bank has suffered extensive habitat damage due to mobile fishing gear (trawls and dredges) and anchoring activities. Structural damage ranges from toppled and broken coral heads to dead coral rubble, the individual pieces of which rarely exceed 2 — 3cm in length (Photo credit: NURC/UNCW).

Oculina Habitat Area of Particular Concern

In 1984, the South Atlantic Council recognized the special significance of the Oculina Bank habitat and designated the Oculina Bank as a Habitat Area of Particular Concern. This action closed a 92–square–kilometer (300 square miles) area to trawling, dredging, longlining, and trapping. Additional restrictions apply to anchoring and possession of rock shrimp and Oculina while in this area.

Oculina Experimental Closed Area (OECA)

In 1994, the SAFMC created the Experimental Oculina Research Reserve (EORR), otherwise known as the Oculina Experimental Closed Area (OECA), which closed the area to all bottom fishing indefinitely. The OECA is located within the Oculina Bank HAPC. All restrictions within the larger HAPC apply. In addition, no person may fish for snapper–grouper species in the area or retain snapper–grouper in or from the area. The area was closed in order to evaluate the effectiveness of the reserve for the management and conservation of reef fish, namely the recovery of fish populations and grouper spawning aggregations.

In response to the 10–year sunset provision for the closure of the OECA, Amendment 13A to the Snapper Grouper Fishery Management Plan was promulgated in 2004 to extend the fishing restrictions for the OECA for an indefinite period. In addition, the Amendment requires that the size and configuration of the OECA be reviewed within three years (2007) and that a 10–year (2014) reevaluation be conducted for the area. The Council also stipulated that an evaluation plan be developed for the area to address the needed monitoring and research, outreach, and enforcement efforts.

The Oculina Experimental Closed Area Evaluation Plan represents a comprehensive approach towards learning more about the resources within the OECA and how management of the area should be effectuated. An Oculina Evaluation Team, composed of individuals knowledgeable about the OECA, was created to review the results of the OEP in 2007 and 2014 (before the three year and 10–year re–evaluation periods, respectively). This team will review the most up-to-date information on the effectiveness of the OECA and provide recommendations to the Council before any significant actions concerning the closed area are carried out.  The first report from the OET was presented to the Council in March 2007.

 Related Sites

Learn more at NOAA’s Coral Reef Information System and Coral Reef Conservation Program.