Understanding the conditions that favor the persistence of metapopulations inhabiting riverine landscapes, or riverscapes, is essential to guiding conservation and restoration efforts aimed at preserving biodiversity and ecological integrity in freshwater environments. Here, we present a modeling framework to examine the transient persistence of fluvial metapopulations—that is, the temporary occupation of riverscape patches by metapopulations ultimately destined for long-term extinction. Our approach is theoretically grounded in the concept of ecological reactivity, which complements asymptotic stability analysis when studying the short-term response of ecological systems to impulsive perturbations of stable steady states. Our results suggest that under ecohydrological conditions conducive to reactive extinction equilibria, a metapopulation can colonize parts of the riverscape for extended periods. Additionally, we find that in the presence of repeated positive perturbations of the extinction equilibrium, the temporal scales associated with these transient phenomena may allow for reactive pseudo-persistence. This phenomenon involves an arbitrarily long delay in the metapopulation's eventual extinction, which may occur well below the deterministic extinction threshold. Identifying the ecohydrological drivers of reactivity-driven metapopulation persistence and the riverscape patches that contribute most to transient metapopulation dynamics over different temporal scales may provide valuable suggestions for the spatial prioritization of conservation and restoration efforts.