This dataset documents the epifauna occurrences collected from 2021 to 2024 during the Canadian Beaufort Sea Marine Ecosystem Assessment (CBS-MEA) conducted by the Department of Fisheries and Oceans (DFO). This scientific program focuses on the integration of oceanography, food web linkages, physical-biological couplings, and spatial and interannual variabilities. The program also aims to expand the baseline coverage of species diversity, abundances, and habitat associations in previously unstudied areas of the Beaufort Sea and Western Canadian Archipelago. The study took place mainly in the Canadian Beaufort Sea and the Amundsen Gulf. Sampling is done along transects at fixed stations in the study area. Catches are collected with a 3 m benthic beam trawl for 10 minutes bottom-contact time at a target speed of 2 knots and with a modified Atlantic Western IIA otter trawl for 20 minutes bottom-contact time at a target speed of 2.9 knots. A total of 32 stations were sampled for epifauna in 2021, 22 in 2022, 23 in 2023 and 22 in 2024, between 22-655 m depth. Epibenthic invertebrates were identified to the lowest taxonomic level possible and photographed. All unknown specimens are frozen. In the lab, the identifications are validated or refined with the photos and the frozen specimens.

The data are presented in Darwin Core and are separated in two files:

The "Activité_épifaune_CBSMEA_epifauna_event_en" file which contains information about missions, stations and deployments, which are presented under a hierarchical activity structure.

The "Occurrence_épifaune_CBSMEA_epifauna_en" file that contains the taxonomic occurrences.