Local contamination, and not feeding preferences, explains elevated PCB concentrations in Labrador ringed seals (Pusa hispida)

摘要: Polychlorinated biphenyls (PCBs) in high trophic level species typically reflect the contributions of myriad sources, such that source apportionment is rarely possible. The release PCBs by a military radar station into Saglek Bay, Labrador contaminated local marine food web. For instance, while heavier (higher chlorinated) PCB profiles some ringed seals (Pusa hispida) were previously attributed to this source, differences feeding preferences among could not be ruled out as contributing factor. Herein, similar fatty acid between those with 'local' and 'long-range' or background indicate little support for possibility differential ecologies underlay divergent profiles. Ringed appeared feed predominantly on zooplankton (Mysis oculata Themisto libellula), followed dusky snailfish (Liparis gibbus), arctic cod (Boreogadus saida), shorthorn sculpin (Myoxocephalus scorpius). Principal components analysis (PCA) homolog illustrated extent contamination web, which had very different (and much heavier) than web members sources. Locally prey levels higher (2- 544-fold) sources exceeded wildlife consumption guidelines PCBs. application multivariate analyses two distinct datasets, including congeners (n=50) acids (n=65), afforded opportunity clearly distinguish contribution locally-released seal from delivered via long-ranged transport. Results present study strongly suggest habitat use rather selection primary mechanism explaining patterns seals.