Combining Survey Methods to Assess Rockfish Critical Habitat Adjacent to Complex Anthropogenic Structures in Puget Sound

The assessment of critical habitat designated for ESA-listed rockfish species in Puget Sound is a high priority when planning species recovery management actions.   Puget Sound contains a diversity of anthropogenic structures and debris, many of which can complicate standard habitat survey methodologies and require the utilization of multiple tools to optimize survey effort and efficiency.   Visual surveys adjacent to complex and/or overhead structures present specific challenges, primarily to identify hazardous features while observing the critical habitat to document species occurrence.  Many factors must be considered when planning and operating any standard remotely operated vehicle (ROV) or SCUBA survey, but the added risk while operating near potentially hazardous submerged structures necessitates alternate methodology and contingency planning.  WDFW has recently observed ESA-listed rockfish species on deep submerged anthropogenic structures in Puget Sound during ROV surveys.  Complex structures such as outfall pipelines, shipwrecks, docks, and military security barriers have been surveyed with a combination of ROV, hydroacoustics, and SCUBA methods to assess the adjacent designated critical habitat.  This presentation focuses on the differential application of alternate methodologies and the nature of results from these visual survey tools that have been effective at observing ESA-listed rockfish and their critical habitat in Puget Sound.