Coral Monitoring
Introduction . Study Area . Land-Sea Interaction . Coral Monitoring . GIS . Bathymetry/Benthic
UWI Coral Reef Ecologist Jennie Mallela, BRT Scientific Diver Richard Parkinson and BRT Boat Captain Rolland "Saga" Guilland on the BRT boat Reef Angel. Map showing locations of the 12 permanent monitoring sites (click for larger version) Coral recruitment experiment Monitoring station transect chain The project has designed and installed twelve fixed monitoring stations around Tobago at a depth of 10 metres. The stations were located at the main coral reefs of the island and are expected to provide long term data on the condition of these ecosystems.
Data collection started with the acquisition of video transects at all sites in January and again in April 2007. The video data are being analyzed to provide an indication of the relative condition of Tobago’s reefs. A third survey has begun.
Methodology and Study Area
Eight of these sites are located on the leeward side of the island (the Caribbean coast), and four of them on the windward front (the Atlantic coast).
The monitoring stations on the Caribbean coast are located at: Mount Irvine, Kariwak reef (in Store bay), Buccoo Reef, Plymouth, Culloden, Little Englishman’s Bay, Sisters Rocks and Pirate’s Bay (in Charlotteville). The four sites on the Atlantic coast are: Bulldog Reef (in Scarborough Bay), Cove Reef, Blackjack Hole and Spiny Colony (the two last ones are in Speyside).
Although the IWCAM project aims to study from Buccoo Reef to Castara, it was decided to study other areas around Tobago to compare the situation of the corals subject to different conditions. This means, that the monitoring stations that are actually inside the project area are Kariwak, Buccoo, Mt. Irvine, Plymouth and Culloden.
Each site consists of three transects, each one of these being 20m long in a straight line at a depth of 10m. This way, a total of 60m in length is surveyed on each monitoring station.
Data Collection and Analysis
The permanent transects are filmed from beginning to end, following a thin chain that is laid along them on every survey. The videos are taken back to the Buccoo Reef Trust office to be analyzed. The video analysis consists on the identification of species of coral and any other benthic live form that is below each mark of the survey chain. These marks on the chain are visible every 10 cm. To organize the data and determine coral cover, a program called CPCe (Coral Point Count with Excel extensions) is used and Microsoft Excel spreadsheets are created to further analyze the data. (This is a modification of the traditional CPCe method)
Sediments are collected as well on a monthly basis. They are brought back to the office to be dried and weighed. Afterwards, they are sent to microscopic analysis at a laboratory at the University of the West Indies in Trinidad.
This research is supported by the IWCAM project. and the University of the West Indies.
