Toxic Chemicals in European Waters Threaten Extinction of Orcas
Posted by feww on January 15, 2016
Killer whales blubber contained “highest concentrations of PCBs on the planet” —Report
Cetaceans are facing the threat of extinction in European waters due to persistent toxic chemicals banned as far back as the 1980s, according to research led by international conservation charity the Zoological Society of London (ZSL) and published in the journal Scientific Reports.
The research, based on long-term studies of more than 1,000 stranded or biopsied whales, dolphins and porpoises – collectively known as cetaceans – found that the blubber of killer whales (Orcinus orca), bottlenose dolphins (Tursiops truncatus) and striped dolphins (Stenella coeruleoalba) in Europe contain among the highest concentrations of polychlorinated biphenyls (PCBs) on the planet.
“The long life expectancy and position as apex or top marine predators make species like killer whales and bottlenose dolphins particularly vulnerable to the accumulation of PCBs through marine food webs. Our findings show that, despite the ban and initial decline in environmental contamination, PCBs still persist at dangerously high levels in European cetaceans,” said Dr Paul Jepson, lead author and specialist wildlife veterinarian at ZSL’s Institute of Zoology.
“Few coastal orca populations remain in western European waters. Those that do persist are very small and suffering low or zero rates of reproduction. The risk of extinction therefore appears high for these discrete and highly contaminated populations. Without further measures, these chemicals will continue to suppress populations of orcas and other dolphin species…”