This data set is a compilation of close to 1000 epifaunal invertebrate sampling stations from over 20 research cruises to the northern Bering Sea (US side), Chukchi Sea (Russian and US sides) and Beaufort Sea (US side) from 1972 to 2012. The vast majority of stations were trawl hauls and a few were photographic sampling stations. Trawl hauls were conducted with a range of different nets including various otter trawls but mostly the 83-112 Eastern Otter trawl, and a plumb-staff beam trawl. Mesh sizes ranged from 4-38 mm in the cod end and 7-89 mm in the body of the net. Trawl duration ranged from 1-30 minutes and trawl speed ranged from 1.5-5 knots. Where available, variables compiled include cruise and station names, locations and water depth, haul and net information, contact information of data holder, as well as total abundance, biomass and taxon richness of epifaunal invertebrates. The latter is biased by varying levels of taxonomic resolution in the source data. Many fields are blank, either because the data have not yet been released as is the case for many recent cruises, or because hauls were not quantitative as is the case for some historic data sets. Data on fishes from the same hauls are not reported here. Column headers are explained in the readme file.

Changes made to the original data sets provided by the project contacts or as found in data archives include, where possible: standardization of abundance to individuals per 1000 square meters; standardization of biomass to kilograms wet weight per 1000 square meters; and subtraction of obvious infaunal taxa, eggs and fragments from the taxon count. This dataset is part of the Pacific Marine Arctic Regional Synthesis (PacMARS) Project.