In this study, a community science campaign was launched to assess geographic and temporal patterns in subtidal bladderwrack (Fucus vesiculosus) -associated invertebrate fauna along the coastal eutrophication gradient of the Finnish Baltic Sea coast in 2020–2021. The community scientists collected the data by collecting a bladderwrack bush, shaking it above a light container, calculating the invertebrate taxa and individuals and measuring the bladderwrack individual. The data collected by the community scientists were quality-controlled and generally similar to scientist-collected data. However, most taxa had somewhat lower abundances than data collected with another, more established sampling method.