Uncertainty is endemic to scientific research practices; therefore, it is also an important element in learning about science. Studies have shown that experiences and management of uncertainty regarding the epistemic practices of science can support learning. Whereas the common strategies of supporting students in handling uncertainty rely on the teacher knowing the preferred outcomes and answers, few studies have explored settings in which no one can give the right answers to students. In this study, we explore how Finnish, suburban secondary school students (aged 13-14 years) respond to epistemic uncertainty during an ecological citizen science inquiry, in which the aim is to produce novel scientific knowledge. Drawing from qualitative interaction analysis of video and interview data, we articulate three responses to uncertainty that arise when students try to make optimal choices during the inquiry: they (a) envision alternative narrative scenarios and hypothesis; (b) accept and maintain it as part of their argumentation practices, and (c) flexibly reframe their research activities and goals. The findings indicate that the citizen science setting can allow students to reframe epistemic uncertainty in ways that are typical of scientific practices even without deliberate scaffolding by the teacher. We suggest that incorporating experiences of uncertainty that are shared by students and teachers in pedagogical design can support doing and learning science in different settings.