This dataset documents the infauna occurrences collected from 2021 to 2023 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 using a 50 x 50 cm box-corer. 2 or 3 box core is collected per station to obtain replicates. A total of 29 stations were sampled for infauna in 2021, 15 in 2022 and 25 in 2023 between 10-653 m depth. Half of the box corer (0.125 m2) is sampled for infauna taxonomy. The first 20 cm of sediment are collected and sieved through a 0.5 mm mesh sieve. The samples are preserved in seawater-formaldehyde solution (10 % v/v). In the lab, infauna is identified to the lowest taxon level possible.

The data are presented in two files:

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

The "Occurrence_endofaune_CBSMEA_infauna_en" file that contains the taxonomic occurrences.