The distribution and abundance of wetland ichthyofauna, and exploitation of the fisheries in the Godineau Swamp, Trinidad--case study.

The Godineau (South Oropuche) Swamp (3171 ha) on the southwestern coast of Trinidad (10 degrees l315'N, 61degrees 30-32'W) is heavily impacted by anthropogenic activities including fishing, oil exploration, drainage manipulation and wetland clearance. To reduce the negative effects of these activities and to manage the swamp more sustainably, more quantitative information is needed on the ecology of the wetland and the activities that occur within it. This study focuses on the distribution of the fish resources and exploited fisheries as a basis for more informed management directives.

A time series of mercury accumulation and improvement of dietary feed in net caged Atlantic salmon (Salmo salar).

The study was undertaken to investigate the uptake of mercury in salmon throughout the entire farming period at the net cage. Mercury concentrations in muscle, liver, kidney, and gill and responses to the various dietary mercury concentrations were determined. The accumulation of mercury is in the order of kidney>gill=liver>muscle.

Improved ultrasonic extraction procedure for the determination of polycyclic aromatic hydrocarbons in sediments.

The aim of this work was to optimize an ultrasonic extraction procedure for the determination of polycyclic aromatic hydrocarbons (PAHs) in sediments and to compare it with the reflux procedure using methanolic potassium hydroxide. Sample extracts were purified with a miniaturized silica gel chromatographic column and analyzed by gas chromatography-mass spectrometry (GC-MS). Ultrasonication using n-hexane-acetone (1:1, v/v) solvent mixture on dried homogenized marine sediment gave better precision (smaller relative standard deviation (RSD) values) and comparable quantities of individual PAH's compared to the reflux procedure.