PurposeInformation practices become highly complex in biodiversity citizen science projects due to the projects’ large scale, distributed setting and vast inclusion of participants. This study aims to contribute to knowledge concerning what variations of information practices can be found in biodiversity citizen science and what these practices may mean for the overall collaborative biodiversity data production in such projects.Design/methodology/approachFifteen semi-structured interviews were carried out with participants engaged with the Swedish biodiversity citizen science information system Artportalen. The empirical data were analysed through a practice-theoretical lens investigating information practices in general and variations of practices in particular.FindingsThe analysis shows that the nexus of biodiversity citizen science information practices consists of observing, identifying, reporting, collecting, curating and validating species as well as decision-making. Information practices vary depending on participants’ technical know-how; knowledge production and learning; and preservation motivations. The study also found that reporting tools and field guides are significant for the formation of information practices. Competition was found to provide data quantity and knowledge growth but may inflict data bias. Finally, a discrepancy between practices of validating and decision-making have been noted, which could be mitigated by involving intermediary participants for mutual understandings of data.Originality/valueThe study places an empirically grounded information practice-theoretical perspective on citizen science participation, extending previous research seeking to model participant activities. Furthermore, the study nuances previous practice-oriented perspectives on citizen science by emphasising variations of practices.