Rice cultivation practices from field preparation to post-harvest transform rice paddies into hot spots for microbial mercury methylation, converting less-toxic inorganic mercury to more-toxic methylmercury, which is likely translocated to rice grain. This review includes 51 studies reporting rice total mercury and/or methylmercury concentrations, based on rice cultivated or purchased in 15 countries. Not surprisingly, both rice total mercury and methylmercury levels were significantly higher in polluted sites compared to non-polluted sites (Wilcoxon rank sum, p<0.001). However, rice percent methylmercury (of total mercury) did not differ statistically between polluted and non-polluted sites (Wilcoxon rank sum, p=0.35), suggesting comparable mercury methylation rates in paddy soil across these sites and/or similar accumulation of mercury species for these rice cultivars. Studies characterizing the effect of rice cultivation under more aerobic conditions were reviewed to determine the mitigation potential of this practice. Rice management practices utilizing alternating wetting and drying (instead of continuous flooding) caused soil methylmercury levels to spike, resulting in a strong methylmercury pulse after fields were dried and reflooded; however, it is uncertain whether this led to increased translocation of methylmercury from paddy soil to rice grain. Due to the potential health risks, it is advisable to investigate this issue further, and to develop separate water management strategies for mercury polluted and non-polluted sites, which minimize methylmercury exposure through rice ingestion.

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Marine mammal exploitation has been documented for the Caribbean in recent times for only a handful of countries. Based on those studies a complex image of how that exploitation has taken place has begun to emerge. In order to fully understand whaling, dolphin fisheries, and manatee hunting, we still need to ascertain patterns of exploitation for many of the island-nations in that part of the world. We present a comprehensive analysis of marine mammal utilisation for Trinidad and Tobago. Trinidad and Tobago has been characterised by landbased whaling, organised during most of the nineteenth century by local elites. Dolphin fisheries have been rare and restricted to by-catches. Trinidad has the last remaining population of manatees among the eastern Caribbean islands, which is composed of a small number of individuals confined to a small swamp.ALDEMARO ROMERO ET AL. 256We compared the history, patterns, and results of this exploitation in Trinidad and Tobago with other neighbouring nations (Venezuela, Grenada, and St. Vincent and the Grenadines). As in other countries in the area that practised intense whaling, local populations of humpback whales have become virtually extinct in their waters. Culture, more than anything else, seems to be the force shaping the nature of marine mammal exploitation in the Caribbean, which has resulted in different histories and methods of exploitation for each one of the countries studied.

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