Metals can have significant impacts on inhabitants of mangrove swamps as well as consumers of mangrove-associated fauna. Yet, for several Caribbean islands, assessments regarding the impact of metals on such ecosystems are particularly sparse. The present study investigated the distribution and potential impact of Cd, Cr, Cu, Ni, Pb and Zn in the Caroni Swamp, Trinidad and Tobago's largest mangrove ecosystem. Surface sediments and mangrove oysters (Crassostrea rhizophorae) from 10 sites in the swamp were analysed for the 6 identified metals. The concentration ranges (in μg/g dry wt.) of metals in sediments from Caroni Swamp were: Zn (113.4-264.6), Cr (27-69.7), Ni (10.7-41.1) and Cu (11-40.7). Based on Canadian Sediment Quality Guidelines (CSQGs), metals in sediments posed a low to medium risk to aquatic life. The concentration ranges (in μg/g wet wt.) for metals in Crassostrea rhizophorae tissues were: Zn (123.2-660), Cu (4.2-12.3), Ni (0.1-5.5), Pb (0.1-0.9), Cr (0.2-0.3) and Cd (0.1-0.2). Multiple evaluations indicated that zinc posed a potential threat to the health of oyster consumers. Information from this study is vital for managing the Caroni Swamp, safeguarding the health of consumers of shellfish on this Caribbean island and serving as a useful baseline for future local and regional risk assessments.

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SummaryProduction data from four breeds of goats (Anglo-Nubian, Saanen, Toggenberg and Alpine), were collected over a five year period to determine the influence of breed, type of birth, sex and year of birth on birth weight, 12-week weaning weight and average daily gain from birth to 12 weeks of age.All factors investigated influenced significantly (P < 0.05) the birth weight. Type of birth was the only factor which did not have a significant influence on the 12-week weight. There were no interactions influencing the birth weight of kids. However, the 12-week weight and average daily gain were influenced by year of birth x sex and year of birth x breed interactions. Loss of kids between years was significantly (P < 0.001) different but there was no difference due to breed, sex and type of birth. The average loss per year was 34 %. Losses ranged from 8 to 53 %.The phenotypic correlations between birth weight and 12-week weight and average daily gain from birth to 12 weeks of age were 0.32 and 0.06, respectively. The phenotypic correlation between 12-week weight and average daily gain was 0.96. Under the system of management, the results suggest that the 12-week weight would provide a good guide for the selection of herd replacements.

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