This study examines the sensitivity of three key marine benthic macroinvertebrates inhabiting subarctic estuaries (Littorina saxatilis, Macoma balthica and Mytilus spp.) to different exposure durations in freshwater. In the laboratory at the Maurice Lamontagne Institute, shellfish were exposed for six weeks to a gradient of 12 pulses of fresh water, ranging from 0 to 9 days, interspersed with 24 hours of exposure to seawater. Mortality was checked daily. Growth was measured from photos taken before the start of the experiment and after two, four or six weeks.
The data made available are the individual data of each individual who was used in the experiment, with their date of death and initial weight. For individuals whose growth was measured, the data include their initial length, width and height and then after two, four or six weeks.
The results of the study are published in the Journal of Experimental Marine Biology and Ecology under the title "Exposure to a gradient of freshwater pulses duration mimicking frequent floodings reveals species-specific vulnerability thresholds in an assemblage of key benthic molluscs" (https://doi.org/10.1016/j.jembe.2025.152120).