In spite of their importance to fish habitat quality and broader ecosystem function, euphausiids have been understudied in the California Current Large Marine Ecosystem. The need for a time-series of euphausiid distribution data has been widely recognized by the IEA, MSE, and in the literature. This project captures the analytic work on euphausiid biomass and distribution that scientists in the FRAM Fisheries Engineering and Acoustic Technologies (FEAT) team will conduct in collaboration with NWFSC-CB, NWFSC-FE, SWFSC-ERD, and Department of Fisheries and Oceans Canada (DFO). A NRC Research Associate (i.e., postdoc) will support this work.

Data on large-scale patterns in euphausiid distribution and abundance are needed for top-down, bottom-up, and climate-related studies. This project will use a time series (2003-2019, n=10 surveys) of coast-wide (BC, WA, OR, CA) acoustic survey data to generate euphausiid distributions and point estimates of euphausiid biomass. Spatiotemporal statistical models will be applied to estimate euphausiid biomass as a function of environmental/habitat covariates. Models results and biomass estimates will then feed into a refinement of a Pacific Hake (Merluccius productus) habitat model to evaluate Hake-habitat linkages (identifier: “Seasonal forecasts of Pacific Hake”) and into growth potential models for Pacific Hake and Sablefish (Anoplopoma fimbria). Results from this work will be incorporated into the Pacific Hake Management Strategy Evaluation (MSE) base operating model. At the end of this project, euphausiid biomass data will be entered into the FRAM Data Warehouse (in conjunction with the FRAM Data Team) and made publically available to meet the requirements of the federal Public Access to Research Results (PARR) policy and facilitate collaborative research within the CCLME. Raw acoustic backscatter (ER 60.raw) and Echolog 60 (Echoview.ek6) data files are logged.