Time series data of demersal fish populations in the Western English Channel sampled using an otter trawl (15m headline) by the Marine Biological Association of the United Kingdom from 2015-2020. This data set contains vertebrate data from 269 trawls. For each trawl, the entire catch was identified to species level. This dataset contains abundance, length, weight and disk width (if applicable) measurements as well as Catch Per Unit Effort calculations. 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. Environmental data (surface and bottom water temperature and salinity) was consistently recorded from 2020. Sensitive species as published by the National Biodiversity Network Trust (available: https://docs.nbnatlas.org/sensitive-species-list/ correct as of 03/02/2021) have been removed from the dataset but can be made available on request.