New evidence that chemical contaminants are finding their way into the deep-sea food web has been found in deep-sea squids and octopods, including the strange-looking "vampire squid". These species are food for deep-diving toothed whales and other predators.
In a study to be published in the journal Marine Pollution Bulletin, Michael Vecchione of NOAA Fisheries' National Systematics Laboratory and colleagues Michael Unger, Ellen Harvey and George Vadas at the Virginia Institute of Marine Science of The College of William and Mary report finding a variety of chemical contaminants in nine species of cephalopods, a class of organisms that includes octopods, squids, cuttlefishes and nautiluses.
"It was surprising to find measurable and sometimes high amounts of toxic pollutants in such a deep and remote environment," Vecchione said. Among the chemicals detected were tributyltin (TBT), polychlorinated biphenyls (PCBs), brominated diphenyl ethers (BDEs), and dichlorodiphenyl-trichloroethane (DDT). They are known as persistent organic pollutants (POPs) because they don't degrade and persist in the environment for a very long time.
Cephalopods are important to the diet of cetaceans, a class of marine mammals which includes whales, dolphins and porpoises. Cephalopods are the primary food for 28 species of odontocetes, the sub-order of cetaceans that have teeth and include beaked, sperm, killer and beluga whales and narwhals as well as dolphins and porpoises.
Recent studies have reported the accumulation of POPs in the blubber and tissues of whales and other predatory marine mammals as well as in some deep-sea fish. Other investigators had speculated that the pollutants in marine mammals had resulted from feeding on contaminated squids. However, almost no information existed prior to this study about POPs in deep-sea cephalopods. Vecchione and colleagues wanted to see if whales had a unique capacity to accumulate pollutants or
|Contact: Shelley Dawicki|
NOAA National Marine Fisheries Service