Responses of Oregon Demersal Species to Seismic Survey Noise: Evaluating Behavior and Movement

Previous investigations into the effects of impulsive anthropogenic noise in the marine environment have focused on mammals, while few have focused on how harvested demersal species may respond behaviorally to this sound. This chapter assesses the impacts of noise borne from a geophysical seismic survey of the Cascadia Subduction Zone along the Oregon coast on the movement and behavior of three fish – lingcod, black rockfish, and China rockfish – and Dungeness crab using telemetry data from an in situ tagging effort in summer 2021 before, during, and after the geophysical seismic survey. Received sound levels were obtained using a vector sensor array and are presented in Raghukumar et al. (this issue). To understand whether the soundscape influences short-term behavior, patterns in detected acceleration and depth were analyzed. Preliminary results presented in this chapter suggest that there are differences in black rockfish instantaneous acceleration as well as distance from the surface in the defined “during” and “after” periods of time as the research vessel passed near the area as compared to the “before” period. There were also differences in China rockfish acceleration during and after as compared to before the period of noise, but there was little difference in acceleration values after the noise event compared to during.