We report the results of a series of experiments investigating the combined effects of ocean acidification and suspended natural benthic sediments (NS) generated during bottom trawling on the early life stages of the cold-water coral Desmophyllum pertusum (syn. Lophelia pertusa). The experiment was conducted at the Tjärnö Marine Laboratory Facilities (University of Gothenburg, Sweden). For each experiment, the larvae/embryos were exposed to four different treatments: (1) current pCO2 (control): mimicking present-day pCO2/pH condition (pCO2 400 µatm; ambient pHT: 8.01), (2) high pCO2: a scenario reflecting the IPCC RCP8.5 prediction (pCO2 1000 µatm; low pHT: 7.63), (3) current pCO2 + NS (5 mg/L), and (4) high pCO2 + NS (5 mg/L): with the introduction of natural benthic sediments (NS) at a concentration of 5 mg/mL. The NS were collected at ~130 m water depth from a regularly trawled soft bottom close to the reef site of Säcken in the Northern Koster-fjord in Sweden, and the grain sizes ≤ 63 μm were used for the experiment. Embryos and larvae were exposed to the different treatments in 75 mL culture flasks mounted on a rotating plankton wheel to keep sediments in suspension. In this first experiment, embryos were exposed for 48 hours to assess potential impacts on larval survival, development from the first division to the blastula stage, and developmental abnormalities. This dataset presents the results for embryo sizes.

Number of larvae or embryos used for the experiments: 30-35 larvae or embryos per replicateIf the Individual ID column is present, each observation corresponds to one larvae.