Current conditions, time trends and recovery targets for toxic contaminants in Puget Sound fish: the Toxics in Fish Dashboard Indicator

Indicators of ecosystem health and related recovery targets have been selected by the Puget Sound Partnership in support of efforts to recover Puget Sound ecosystem health by 2020. This Dashboard of Indicators is meant to define expectations for recovered conditions, or a trajectory towards such conditions, for a wide range of ecosystem Vital Signs. They reflect an effort to simplify science reporting and link it to policy, ultimately resulting in easily communicated policy statements (i.e., targets) that define the desired condition or goals.

The Toxics in Fish indicator condenses key information regarding exposure of Puget Sound biota to toxic contaminants, harmful effects from such exposure, and time-trends in exposure-and-effects. This indicator relies on three species representing key food-web pathways: (1) a bottom-dwelling flatfish, English sole (Parophrys vetulus), (2) a small, schooling mid-water planktivore, Pacific herring (Clupea pallasii), and (3) Pacific salmon species, including coho salmon (Oncorhynchus kisutch) and Chinook salmon O. tshawytscha). English sole represent the sediment-to-biota contaminant link for contaminants that tend to accumulate in sediments. Pacific herring are prey to virtually every large piscivorous species in Puget Sound, and so generally represent the pathway of contaminants to higher level predators including Pacific salmon, seabirds, and killer whales. Coho and Chinook salmon are short-lived, highly migratory and anadromous species that reflect a combination of oceanic and Puget Sound conditions. They also represent a pathway of contaminants from fish to humans.

Although these three species are typically exposed to a wide range of toxic contaminants, the Toxics in Fish indicator focuses on three classes: (1) persistent bioaccumulative toxics such as polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs), (2) polycyclic aromatic hydrocarbons (PAHs), and (3) endocrine disrupting compounds (EDCs). Although there is crossover between some individual chemicals among these groups and this list is not comprehensive, organizing results by these contaminant groups helps to simplify communication.