title: Modulation in Persistent Organic Pollutant Concentration and Profile by Prey Availability and Reproductive Status in Southern Resident Killer Whale Scat Samples.
abstract: Persistent organic pollutants (POPs), specifically PCBs, PBDEs, and DDTs, in the marine environment are well documented, however accumulation and mobilization patterns at the top of the food-web are poorly understood. This study broadens the understanding of POPs in the endangered Southern Resident killer whale population by addressing modulation by prey availability and reproductive status, along with endocrine disrupting effects. A total of 140 killer whale scat samples collected from 54 unique whales across a 4 year sampling period (2010-2013) were analyzed for concentrations of POPs. Toxicant measures were linked to pod, age, and birth order in genotyped individuals, prey abundance using open-source test fishery data, and pregnancy status based on hormone indices from the same sample. Toxicant concentrations were highest and had the greatest potential for toxicity when prey abundance was the lowest. In addition, these toxicants were likely from endogenous lipid stores. Bioaccumulation of POPs increased with age, with the exception of presumed nulliparous females. The exceptional pattern may be explained by females experiencing unobserved neonatal loss. Transfer of POPs through mobilization of endogenous lipid stores during lactation was highest for first-borns with diminished transfer to subsequent calves. Contrary to expectation, POP concentrations did not demonstrate an associated disruption of thyroid hormone, although this association may have been masked by impacts of prey abundance on thyroid hormone concentrations. The noninvasive method for measuring POP concentrations in killer whales through scat employed in this study may improve toxicant monitoring in the marine environment and promote conservation efforts.
authors.affiliation: Center for Conservation Biology, Department of Biology, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Jessica I
authors.initials: JI
authors.lastname: Lundin
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.
authors.forename: Gina M
authors.initials: GM
authors.lastname: Ylitalo
authors.affiliation: Center for Conservation Biology, Department of Biology, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Rebecca K
authors.initials: RK
authors.lastname: Booth
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.
authors.forename: Bernadita
authors.initials: B
authors.lastname: Anulacion
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Hempelmann
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.|Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98115, United States.
authors.forename: Kim M
authors.initials: KM
authors.lastname: Parsons
authors.affiliation: Center for Whale Research , Friday Harbor, Washington 98250, United States.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Giles
authors.affiliation: Center for Conservation Biology, Department of Biology, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Seely
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.
authors.forename: M Bradley
authors.initials: MB
authors.lastname: Hanson
authors.affiliation: Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration , Seattle, Washington 98112, United States.
authors.forename: Candice K
authors.initials: CK
authors.lastname: Emmons
authors.affiliation: Center for Conservation Biology, Department of Biology, University of Washington , Seattle, Washington 98195, United States.
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Wasser
mesh_terms: D000818:Animals; D004784:Environmental Monitoring; D055768:Halogenated Diphenyl Ethers; D011078:Polychlorinated Biphenyls; D012098:Reproduction; D050685:Whale, Killer
chemical_list: D055768:Halogenated Diphenyl Ethers; D011078:Polychlorinated Biphenyls