Our oceans are critical to the health of our planet and its inhabitants. Increasing pressures on our marine environment are triggering an urgent need for continuous and comprehensive monitoring of the oceans and stressors, including anthropogenic activity. Current ocean observational systems are expensive and have limited temporal and spatial coverage.
View Article and Find Full Text PDFThe source level (SL) and vocalizing source depth (SD) of individuals from two blue whale (BW) subspecies, an Antarctic blue whale (Balaenoptera musculus intermedia; ABW) and a Madagascar pygmy blue whale (Balaenoptera musculus brevicauda; MPBW) are estimated from a single bottom-mounted hydrophone in the western Indian Ocean. Stereotyped units (male) are automatically detected and the range is estimated from the time delay between the direct and lowest-order multiply-reflected acoustic paths (multipath-ranging). Allowing for geometric spreading and the Lloyd's mirror effect (range-, depth-, and frequency-dependent) SL and SD are estimated by minimizing the SL variance over a series of units from the same individual over time (and hence also range).
View Article and Find Full Text PDFTwelve air samples collected over the Indian Ocean by a high volume air sampler between August 2004 and August 2005 were analyzed for selected polychlorinated biphenyl (PCB) congeners and organochlorine pesticides. The region of the Indian Ocean and adjacent countries is likely to be acting as a source of selected POPs to the global environment. Data were compared with those reported for the last 30 years to examine historical trends of selected persistent organic pollutants (POPs) over the Indian Ocean.
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