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This paper provides an analysis of the distribution patterns of marine biodiversity and summarizes the major activities of the Census of Marine Life program in the Caribbean region. The coastal Caribbean region is a large marine ecosystem (LME) characterized by coral reefs, mangroves, and seagrasses, but including other environments, such as sandy beaches and rocky shores. These tropical ecosystems incorporate a high diversity of associated flora and fauna, and the nations that border the Caribbean collectively encompass a major global marine biodiversity hot spot. We analyze the state of knowledge of marine biodiversity based on the geographic distribution of georeferenced species records and regional taxonomic lists. A total of 12,046 marine species are reported in this paper for the Caribbean region. These include representatives from 31 animal phyla, two plant phyla, one group of Chromista, and three groups of Protoctista. Sampling effort has been greatest in shallow, nearshore waters, where there is relatively good coverage of species records; offshore and deep environments have been less studied. Additionally, we found that the currently accepted classification of marine ecoregions of the Caribbean did not apply for the benthic distributions of five relatively well known taxonomic groups. Coastal species richness tends to concentrate along the Antillean arc (Cuba to the southernmost Antilles) and the northern coast of South America (Venezuela – Colombia), while no pattern can be observed in the deep sea with the available data. Several factors make it impossible to determine the extent to which these distribution patterns accurately reflect the true situation for marine biodiversity in general: (1) highly localized concentrations of collecting effort and a lack of collecting in many areas and ecosystems, (2) high variability among collecting methods, (3) limited taxonomic expertise for many groups, and (4) differing levels of activity in the study of different taxa.

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Macrobenthic species abundances and blomasses were determined at 31 statlons from Pointe-a-Plerre to La Brea, Trinldad. Thls area is subject to chronic natural 011 seepage and spillage from oil production activities. Multivariate analysis was used to define those environmental variables which best explained community composition. The deeper sltes were impoverished due to the development of anoxia below a pycnocline which formed during the wet season. Abundance/biomass comparison (ABC) plots indicated that macrobenthic communltles near an oil refinery were grossly to moderately stressed while those close to the Trinidad Pltch Lake, one of the largest natural oil seeps In the world, were not. Taxonomic aggregation of the species data to family level resulted In little loss of information in the multlvarlate analyses and apparently Improved the ability of ABC curves to discriminate pollution. Comparisons of the severity of community degradation at these sites using a phylum-level meta-analysis of 'production' were compatible with NE Atlantlc data, which augurs well for the more global applicability of this approach. A feature of the Tnnidad samples is that they all separate along the upper edge of the meta-analys~s 'wedge', due malnly to their higher average proportion of Crustacea relative to Echlnodermata and Mollusca. This IS explained In terms of the estuarine character of the reglon, and suggests that the unexplained vertlcal axis in Warwick & Clarke's (companion article) ordination may be related to natural environmental characteristics INTRODUCTIONOne of the challenges of the benthic community approach to pollution monitoring is to develop a suite of objective analytical protocols which are easy to apply and accessible to laboratories with less sophisticated resources. Comparison of several appropriate methods which may fit these criteria (Gray et al. 1988) shows that they give essentially the same results for a strong pollution gradient (Warwick 1 9 8 8~) .Further, there is little if any loss of information if the data are analysed at higher taxonomic levels (Warwick 1988a, b, Ferraro & Cole 1990, and phylum-level analysis may permit comparative studies of the severity of pollution effects from physically dlssirnilar and geographically distant areas (Warwick & Clarke 1993). These findings may be helpful in many areas of the tropics where the taxonomy of the benthic fauna is not well-known or well-documented. However, the question remains as to whether such techniques are drectly applicable to these areas. In particular, the phylum-level meta-analysis approach has only been applied to NE Atlantic sites. Since it depends on a predictable phyletic composition in unperturbed situations and also on predictable changes in this composition with increasing levels of perturbation, its validity for use on a more global scale needs testing. Here we have done t h s in a tropical setting where natural and man-induced perturbations are many and varied. Firstly, we have assessed the level of community degradati...

Assemblages associated with intertidal rocky shores were examined for large scale distribution patterns with specific emphasis on identifying latitudinal trends of species richness and taxonomic distinctiveness. Seventy-two sites distributed around the globe were evaluated following the standardized sampling protocol of the Census of Marine Life NaGISA project (www.nagisa.coml.org). There were no clear patterns of standardized estimators of species richness along latitudinal gradients or among Large Marine Ecosystems (LMEs); however, a strong latitudinal gradient in taxonomic composition (i.e., proportion of different taxonomic groups in a given sample) was observed. Environmental variables related to natural influences were strongly related to the distribution patterns of the assemblages on the LME scale, particularly photoperiod, sea surface temperature (SST) and rainfall. In contrast, no environmental variables directly associated with human influences (with the exception of the inorganic pollution index) were related to assemblage patterns among LMEs. Correlations of the natural assemblages with either latitudinal gradients or environmental variables were equally strong suggesting that neither neutral models nor models based solely on environmental variables sufficiently explain spatial variation of these assemblages at a global scale. Despite the data shortcomings in this study (e.g., unbalanced sample distribution), we show the importance of generating biological global databases for the use in large-scale diversity comparisons of rocky intertidal assemblages to stimulate continued sampling and analyses.

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