Assessing Land-Based Impacts to Spawning Habitat of Surf Smelt

The three most abundant forage fish species in the Salish Sea, Pacific herring (Clupea pallasi), surf smelt (Hypomesus pretiosus), and sand lance (Ammodytes hexapterus), all spawn in nearshore shallow subtidal or intertidal habitat. These habitats are also the areas of the Salish Sea most likely to receive significant inputs of land-based pollution, such as stormwater runoff, combined sewer overflows, or surface oil spill “bathtub rings”. Although methods exist to deploy caged herring embryos as tools to measure the biological effects of in situ exposure, these methods are restricted to investigations of the shallow subtidal zone. The potential impact of oil spills on surf smelt and sand lance was identified as a key data gap in Puget Sound. Surf smelt are obligate intertidal spawners resulting in different exposure characteristics and life history-specific physiological requirements that could modify their sensitivity or responses to pollutant exposure. Here we describe in situ methods for deploying surf smelt embryos in Puget Sound beaches intended to improve contaminant monitoring in intertidal habitats.