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Abstract Climate change is leading to global increases in extreme events, such as drought, that threaten the persistence of freshwater biodiversity. Identification and management of drought refuges, areas that promote resistance and resilience to drought, will be critical for preserving and recovering aquatic biodiversity in the face of climate change and increasing human water use. Although several reviews have addressed the effects of droughts and highlighted the role of refuges, a need remains on how to identify functional refuges that can be used in a drought management framework to support fish assemblages. We synthesize literature on drought refuges and propose a framework to identify and manage functional refuges that incorporate species physiological tolerances, behaviours and life‐history strategies. Stream pools, perennial reaches and off‐channel habitat were identified as important drought refuges for fish. The ability of refuges to improve species resistance and resilience to drought requires careful consideration of the biology of the target species and targeted management to promote persistence, quality and connectivity of refuges. Case studies illustrate that management of drought refuges can be challenging because of competing demands for water, incomplete knowledge of ecological requirements for target species and the increasing occurrence of multi‐year droughts. Climate adaptation is increasingly important, and drought refuges can increase fish resistance and resilience to climate‐related drought across the riverscape. 

Abstract Rivers that do not flow year-round are the predominant type of running waters on Earth. Despite a burgeoning literature on natural flow intermittence (NFI), knowledge about the hydrological causes and ecological effects of human-induced, anthropogenic flow intermittence (AFI) remains limited. NFI and AFI could generate contrasting hydrological and biological responses in rivers because of distinct underlying causes of drying and evolutionary adaptations of their biota. We first review the causes of AFI and show how different anthropogenic drivers alter the timing, frequency and duration of drying, compared with NFI. Second, we evaluate the possible differences in biodiversity responses, ecological functions, and ecosystem services between NFI and AFI. Last, we outline knowledge gaps and management needs related to AFI. Because of the distinct hydrologic characteristics and ecological impacts of AFI, ignoring the distinction between NFI and AFI could undermine management of intermittent rivers and ephemeral streams and exacerbate risks to the ecosystems and societies downstream.