Time series data of demersal fish populations in the Western English Channel sampled using a large otter trawl (15m headline) by the Marine Biological Association of the United Kingdom from 2015-2018. This data set contains vertebrate data from 108 trawls. For each trawl, the entire catch was identified to species level. This dataset contains abundance, length, weight and disk width (if applicable) measurements. This dataset contains consistent sex data for elasmobranchs. Invertebrate abundance data was also collected on each survey and is available on request to MBASepia@mba.ac.uk. These data include high confidence cephalopod, scallop and large crab abundance as well as counts of other invertebrates including other crustaceans and echinoderms.