title: Effects of age, sex and reproductive status on persistent organic pollutant concentrations in "Southern Resident" killer whales.
abstract: "Southern Resident" killer whales (Orcinus orca) that comprise three fish-eating "pods" (J, K and L) were listed as "endangered" in the US and Canada following a 20% population decline between 1996 and 2001. Blubber biopsy samples from Southern Resident juveniles had statistically higher concentrations of certain persistent organic pollutants than were found for adults. Most Southern Resident killer whales, including the four juveniles, exceeded the health-effects threshold for total PCBs in marine mammal blubber. Maternal transfer of contaminants to the juveniles during rapid development of their biological systems may put these young whales at greater risk than adults for adverse health effects (e.g., immune and endocrine system dysfunction). Pollutant ratios and field observations established that two of the pods (K- and L-pod) travel to California to forage. Nitrogen stable isotope values, supported by field observations, indicated possible changes in the diet of L-pod over the last decade.
authors.affiliation: NOAA Fisheries, Northwest Fisheries Science Center, National Marine Fisheries Service, 2725 Montlake Boulevard East, Seattle, WA 98112, USA. peggy.krahn@noaa.gov
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Krahn
authors.forename: M Bradley
authors.initials: MB
authors.lastname: Hanson
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Schorr
authors.forename: Candice K
authors.initials: CK
authors.lastname: Emmons
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Burrows
authors.forename: Jennie L
authors.initials: JL
authors.lastname: Bolton
authors.forename: Robin W
authors.initials: RW
authors.lastname: Baird
authors.forename: Gina M
authors.initials: GM
authors.lastname: Ylitalo
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry*; D000367:Age Factors; D025041:Animal Migration; D000818:Animals; D002247:Carbon Isotopes / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D004785:Environmental Pollutants / Q000032:analysis*; D005260:Female; D055768:Halogenated Diphenyl Ethers / Q000032:analysis*; D008297:Male; D009587:Nitrogen Isotopes / Q000032:analysis; D019370:Observation; D010140:Pacific Ocean; D012098:Reproduction / Q000502:physiology*; D012737:Sex Factors; D050685:Whale, Killer / Q000502:physiology*
chemical_list: D002247:Carbon Isotopes; D004785:Environmental Pollutants; D055768:Halogenated Diphenyl Ethers; D009587:Nitrogen Isotopes