Live-blog: Sandra O'Neill — Puget Sound toxics

Toxics in the Puget Sound Food Web: Understanding the Problem in Order to Move Towards Improvement (Sandra is from WDFW; this was a Monster Jam presentation at NWFSC/NOAA)

11:03 Intro from Tracy in Korea

11:08 Data presented today are mostly collected through the Puget Sound Assessment and Monitoring Program (PSAMP).  Jim West of WDFW and Steve ?? are collaborators.

11:10 Outline:

  1. Assessing pollution impacts on biota
  2. Three case studies (POPs, PAHs, EDCs)
  3. How should science proceed?

11:11 Assessment of impacts on biota can happen on many scales from micro-organisms to entire ecosystems.  Policy makers usually don’t respond unless it is a major threat to ecosystem, and the “eye-lid factors” are really only: ESA listed species, potential economic losses, human health threat.  PCBs are a good example of dramatic polcy change (ban) and subsequent decrease in pollution (concentration in PS Chinook) in late 80s, but implications for killer whales (and their policy makers) weren’t clarified until recently: Hickie et al., 2007 PcB levels in PS salmon may impair health of killer whales

11:16 Case studies

A) POPs (PCBs and Polybrominated Diphenyl Ethers = PDBEs)

  • Long et al., 2005 Envir. Monitoring and Assess. 111:173-222: “Relative to many other estuaries… in USA, PS sediments ranked among those with minimal evidence of toxicant-induced degradation.”  Though there are pollution hot spots (Vancouver, Everett, Seattle) in bays, PS overall is very deep and most of it is well away from the hot spots).
  • PCB in English sole muscle increases linearly with PCB in adjacent sediment.
  • PCB’s biomagnify: muscle concentrations along Seattle waterfront are 62 micrograms/kg for English sole avg, 100 for female rockfish avg, and 250 for male rockfish avg because they don’t shed PCBs in egg lipids as females do.
  • Herring in central basin of PS have higher [PCB] than in San Juans or Georgia Basin: 150 ng/g wet wt in South PS, vs 140 in Central PS, 30 in N PS, and <10 off WA/BC coasts and in SF Bay.  For PDBEs in herring, 45ng/g in S PS, 50 in central PS, <10 N PS, <5 off WA/BC coasts and in SF Bay.
  • So why is pelagic food web so contaminated?  Short answer: PS is deep and hydrologically constricted, so it’s exchange is limited and its biota are isolated (herring and some Chinook are resident).
  • Gina Yltalo collaborated on KW prey study: contaminant levels in coho, Chinook, pink, chum, and sockeye from low to high human population areas.  Sockeye were Fraser River collected in San Juans.  Chinook were collected more broadly, up and down coast N BC to CA.  Results: pink, chum, sockeye are all clean (non-detectable); Coho <1 ng/g offshore, ~5 ng/g [PBDE] in PS; Chinook <2.5 offshore, ~20 in PS.  THIS IMPLIES THERE *ARE* CLEAN FISH AVAILABLE TO KILLER WHALES, JUST DON’T FORAGE IN PUGET SOUND?
  • Why are PS Chinook so contaminated?  Hypothetically, it is because their migration pattern is more loca: loop migrants vs ocean migrants.  Stable isotopes of PS Chinook are similar to non-PS, implying that they’re eating similar prey.  So maybe their eating in different areas… Since 1950’s we’ve known there is a residnent population of  Chinook — the “blackmouth.”  PS Chinook have highly variable muscle concentrations (up to 10x difference).
  • Coded wire tag data in : O’Neill and J.E. West 2008 Marine distribution, life history traits, and the accumulation of polycholinated biphenyls in Chinook salmon in Puget Sound (in review, TAFS).  Percentage of recreational and commercial catch of PS Chinook salmon displaying resident behavior from coded wire tag data: 29% of sub-yearly smolts, 49% yearling smolts.
  • Fillet data: PCBs in Chinook — 404 samples from Nooksack, to Deschutes, mostly sampled in commercial fisheries.  TPCB (ng/g lipid normalized) for 29% of PCB fillets (’92-’96) meet or exceed the  threshold for adverse health effect in salmon (2500 ng/g).
  • S Resident male biopsy [PCB}: 66,000 ng/g lipid for SRKW

11:39 PAHs

  • Polycyclic aromatic hydrocarbons don’t bioaccumulate, but they harm fish when metabolized
  • Same patterns as in PCBs: herring have highest concentrations in central Sound (e.g. Port Orchard)
  • Herring eggs are very sensitive to PAHs (lab studies are using Zebra fish as a model for Pacific herring); some evidence of reduced growth in juvenile salmon.

11:45 Endocrine disrupting chemicals

  • capable of acting as hormone mimics (impaired reproduction, sex switching, etc)

11:48 What’s next for science and policy

  • Biota vector of pollution is clearly important for chemicals that biomagnify (don’t eat ratfish!)
  • PAHs appear to be important for some species

11:51 End, questions

  1. What about pollution in plankton?  The plankton all have lipid sacks and we expect both phytoplankton and zooplankton to be contaminated.  Bethic organisms emit fatty things (eggs, sperm, larvae) into water column which are a vector from sediment to pelagic plankton and fish.  There are some fledgling, small, underfunded efforts to look at out-migrating Juvenile salmon.
  2. Do some of these chemicals impair fish’s ability to evade predators?  It’s been looked at for other chemicals.
  3. Are POP concentrations different enough in salmon between PS and the San Juans/Georgia Basin that we should prevent SRKWs from foraging in PS?

Unasked: Does J pod have higher [POP] than K or L? Or do blackmouth move between these regions and blur [PCB] gradients?


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