Coral Reef Monitoring for Climate Change Impacts: Jamaica 2000-2003

Study Extent

The Site Selection Protocol stipulated that at least three areas should be monitored in each of the pilot countries and these should be representative of pristine, mildly impacted and severely-impacted conditions. In this instance, impact was defined as land-based, anthropogenic impacts, transported to reefs by fluvial inputs or actual physical impacts on reefs caused by activities within the marine environment. The "pristine" location extended along the relatively undisturbed coastline, containing numerous fringing coral reefs. The monitoring area was located approximately 10 km east of Port Antonio, in the parish of Portland and situated away from any major land-based influences, and extending due north of Monkey Island and eastwards to the Blue Hole area following the 7 – 13 meter depth contour. The monitoring site, located to the west of Discovery Bay at “Gorgo City” reef was selected as the mildly impacted location. Activities within this area included a port exporting bauxite as well as fishing, tourism, research and teaching. The monitoring site has a gentle profile between the depths of 7-13 meters The Port Royal site represented the heavily impacted site, being close to a major city and also being down current of several major rivers. The specific monitoring site is located within the Port Royal Cays, which is a collection of eight small coral islets (Gun Cay, Rackhams Cay, Lime Cay, Drunkenman’s Cay, East Middle Ground, South Cay, Southeast Cay and Maiden Cay) situated on the island shelf of the south coast of Jamaica. The Port Royal Cays are an important nearshore fishery site for the artisanal fishing industry serving the nearby fishing communities.

Sampling

The benthic cover of the coral reefs was monitored using underwater videography. The divers used a high-resolution digital video camera fitted with a wide-angle lens and underwater housing. The diver videotaped while swimming slowing along the transect holding the camera perpendicular to the substratum at a height of 40 cm (guided by a 40 cm wand attached to the camera housing) in order to provide a belt transect that was approximately 40 cm wide . A total of 20 transects each 20 m in length were monitored at each location. The resultant videotapes were viewed to ensure that clarity and resolution were satisfactory, after which the tapes were numbered and catalogued and the content of each tape logged to ensure that the individual transects at each site could be located at a later date with relative ease. A computer was connected to a videotape player and the tape played to “capture” adjacent, non-overlapping images (photo quadrats) which where converted to photo files and saved in an image library. Ten random dots were placed on each image during a process that uses Microsoft Excel and Adobe Photoshop and was automated by WinBatch for Windows (a batch processing program). After the image has been processed, the data analyst identified the benthic components under the random dots while viewing the images in Adobe Photoshop. Data points were identified to species (where possible) or to higher functional taxonomic groups. Other substrate categories included the hard substrate (sand, rubble, pavement etc), points falling on equipment (e.g. tape, wand etc) and areas that could not be identified (shadow and unknown). These data were entered into data sheets developed in Microsoft Excel, which automatically tabulated and grouped the substrate categories and calculated the percentage cover and standard deviation.

Quality Control

Video taping was carried out by trained and experienced divers. Data analysis was undertaken by marine biologist trained in the identification of marine benthic species.

Method steps

1. Site selection was based on the following document:
   Woodley. J. (1999) Component 5: Coral Reef Monitoring Site Selection Protocol (Draft). CPACC. (Available at the UWI-Centre for Marine Sciences)
2. Video monitoring was carried out based on the methods outlined in the following document: Miller, J. (2000) Using Videotape to Sample Coral Reefs. US Geological Survey. Biological Resources Division. Virgin Islands Field Station. St. John, USVI. (Available at the UWI-Centre for Marine Sciences)

The three Operational Areas that were selected for monitoring in Jamaica were Eastern Portland (minimally impacted), Discovery Bay in St Ann (mildly impacted) and Port Royal Cays in Kingston (severely impacted).