Contribution of combined stressors on abundance and gene expression dynamics of the copepod Temora longicornis in the North Sea

The impact of multiple environmental and anthropogenic stressors on the marine environment remains poorly understood. Therefore, we studied the contribution of environmental variables to the densities and gene expression of the dominant zooplankton species in the Belgian part of the North Sea, the calanoid copepod Temora longicornis. We observed a reduced abundance of copepods, which were also smaller in size, in samples taken from nearshore locations when compared to those obtained from offshore stations. To assess the factors influencing the population dynamics of this species, we applied generalized additive models. These models allowed us to quantify the relative contribution of temperature, nutrient levels, salinity, turbidity, concentrations of photosynthetic pigments, as well as chemical pollutants such as polychlorinated biphenyls and polycyclic aromatic hydrocarbons, on copepod abundance. Temperature and Secchi depth, a proxy for turbidity, were the most important environmental..., Material & Methods
Zooplankton were sampled with research vessel Simon Stevin on 33 sampling missions in 2018 till 2021 (starting on 20th of February 2018, ending on 22nd of December 2021) at four sampling locations in the Belgian part of the North Sea (BPNS). During 2018 and 2019, samples were collected in bi-monthly sampling campaigns. Due to the prevailing precautions prompted by the COVID-19 pandemic in 2020, the sampling strategy was adjusted for the remainder of the study period, leading to the collection of monthly samples due to the uncertain situation and prevailing regulations. For this study, two nearshore stations (130 and 230) and two offshore stations (215 and 330) were selected. Stations 130 and 230 are in proximity to the Ostend harbour in Belgium, with maximum depths of 13.8 and 16.7 m, respectively. Offshore station 215, maximum 29 m deep, is situated on the Flemish banks in the western region of the BPNS, while offshore station 330 (with a maximum depth of 25.9 m)..., , # Contribution of combined stressors on abundance and gene expression dynamics of the copepod Temora longicornis in the North Sea

[https://doi.org/10.5061/dryad.s7h44j1f1](https://doi.org/10.5061/dryad.s7h44j1f1)

The impact of multiple environmental and anthropogenic stressors on the marine environment remains poorly understood. Therefore, we studied the contribution of environmental variables to the densities and gene expression of the dominant zooplankton species in the Belgian part of the North Sea, the calanoid copepod *Temora longicornis*.

## Description of the data and file structure

The uploaded datafile gives a summary of plankton/environmental sample collections taken in 2018-2021, with sampling date and location and measured environmental parameters. Average copepod body length, prosome length and weight (body mass) are reported as well. It consists of one matrix: each column contains metadata (location and time of sampling, as well as the measured environmental variables,...