Clupeids and stickleback biomass, fishery landings, and hydrographic variables from the Baltic Sea

Description of the data and file structure: data on fish biomass, fishery landings and hydrographic variables from the Baltic Sea. The data were used to explore the relationships between clupeids and three-spined stickleback, specifically whether reduced predation from herring and competition from both sprat and herring may have contributed to the recent increase of three-spined stickleback in the Baltic Sea.
The data is structured in six separate datasets. Each record report values of fish biomass or abiotic variables related to a specific ICES statistical rectangle (ca. 55 × 55 km size, corresponding to 0.5 degrees in latitude × 1 degree in longitude) and a specific year. The datasets can be merged using the field "year" and "ICES". The files have the following dimensions: ICES_Hydrographic_data_by_year.csv, 4465 rows × 20 columns; herring_biomass.csv, 2056 rows × 5 columns; landings_herring.csv, 2867 rows × 3 columns; landings_sprat.csv, 2108 rows × 3 columns; sprat_biomass.csv, 2042 rows × 4 columns; stic