Safeguarding, strengthening, and scaling river protections for freshwater biodiversity

Despite recent commitments to protect freshwater ecosystems globally, significant uncertainty remains about our ability to achieve protection goals to sustain the benefits rivers provide to people and nature. A major barrier to action is an incomplete understanding of the status of river protection – most existing assessments measure only where rivers overlap with terrestrial protected areas – and spatially limited evaluations of how these protections coincide with, or are misaligned from, freshwater biodiversity. As momentum builds to tackle the freshwater biodiversity crisis and meet national and global conservation targets, we face the urgent challenge of determining which rivers to prioritize for future protection and where to reinforce and safeguard existing protections. The goals of this presentation are threefold. First, the results of the Protected Rivers Assessment of the United States are presented – a comprehensive investigation of the regulatory frameworks, conservation policies, and management practices across federal, state, local, tribal, and private jurisdictions that aim to protect rivers, riparian zones, floodplains, and surrounding lands. Second, a novel class of scalable spatial stream network models is applied and coupled with fish community data from > 1 million fish observations across the United States, to forecast fish species abundance across > 7 million river kilometers and to evaluate spatial congruence with river protection status. Third, network-based prioritization algorithms are used to identify priority areas for safeguarding/strengthening existing and scaling new protections that: (1) reduce stranded protections, increase protection river lengths, and enhance watershed dendritic connectivity; (2) best capture the distributional core and range of threatened and endangered species and native species that are currently under-protected; and (3) represent fish biodiversity strongholds with respect to taxonomic and functional alpha- and beta-diversity. Results from this assessment seek to inform new conservation priorities by aiding decision-makers who currently lack the data and tools to evaluate and track progress toward stronger, more durable river protections for freshwater biodiversity.