Roving surveys were also undertaken to characterize species diversity.ĭata analysis: All data were initially entered into Microsoft Excel spreadsheets with PRIMER software used for graphical and comparative analysis. The assessment focused on species that are ecologically relevant to the health of reefs and also important for commercial or recreational fisheries, with emphasis on herbivores, invertivores and larger piscivores. All species were identified and their size was estimated to the nearest 5cm using a T-bar marked in 5cm increments for scale. Reef fish: The reef fish assemblage (approximately 70 species) was quantified within a minimum of six 30 x 2m belt transects per site (187 transects total). Invertebrates were also counted and recorded within coral belt transects. Additional roving surveys were undertaken to assess presence of invertebrates in cryptic areas, including ledges and caves. One diver would extend a 10m line from a central point and then swim slowly in a circle while a second diver would record the numbers of each species of invertebrate seen within the plot. Motile invertebrates: The abundance of large motile invertebrates (crustaceans, molluscs and echinoderms) was quantified using random circular plots, each 10m diameter (total area = 314 m 2 ), with 1-4 plots assessed per reef. Recruits were divided into two categories: <2cm diameter and 2-3.9cm diameter. Recruits were identified in both benthic and coral transects. The abundance of recruits (corals smaller than 4cm) was assessed using a minimum of five 0.25m 2 quadrats per transect, with each quadrat located at fixed, predetermined intervals (2, 4, 6, 8, 10m, alternating between right and left side of the transect line). black band disease, yellow band disease, dark spots disease) was assigned. The location (apical, basal, medial) and pattern of tissue loss (linear, annular, focal, multifocal, and coalescing) were recorded, and a field name (e.g. Lesions were diagnosed into four categories: recent tissue loss, skeletal damage, color change, and unusual growth patterns an individual colony could have multiple characteristics (e.g. Each coral was first carefully examined to identify cryptic predators. The diagnosis included an assessment of the type of disease, extent of bleaching, predation, competition, overgrowth or other causes of mortality. For each coral with partial or whole colony mortality, the cause of mortality was identified if possible. While parrotfish were the most abundant fish, these were all extremely small (mean size= 12cm 30 days). Fish biomass at all sites near the Cays was low, with a dominance of herbivores (parrotfish and surgeonfish) and a near absence of groupers, snappers and other commercially important species. Macroalgal cover at all sites was relatively low, with only three sites having greater than 30% cover crustose coralline algae (CCA) was high, with eight sites exceeding 20% cover. A single area, within the proposed fishery reserve, had extensive Acropora cervicornis thickets, and several shallow locations had small, but recovering A. faveolata, and these were generally in good condition. Agaricia, Porites and Siderastrea) although many sites had high abundances of large colonies of Montastraea annularis and M. Coral communities were dominated by small corals (esp. Within 20 reefs, live coral cover ranged from 4.9% to 19.2%. This work was conducted to assist in characterizing coral reef habitats within and outside a proposed fishery reserve, and identify other possible conservation zones. The main objectives were to: 1) characterize the distribution, structure and health of coral reefs and 2) evaluate the population status of commercially important reef fishes and invertebrates. Coral reefs of Pedro Bank, Jamaica were assessed in March, 2012 as part of the KSLOF Global Reef Expedition using a modified Atlantic and Gulf Rapid Reef Assessment (AGRRA) protocol. The coral reefs located off the north coast of the Jamaican mainland are some of the best and most studied reefs in the world.
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