Dam development is fragmenting migratory pathways in the Mekong Basin, yet scientific understanding of Mekong fish migrations is limited. Therefore, the first‐ever transboundary acoustic telemetry network was deployed in the Mekong, Sekong, and Sesan rivers in Cambodia and Lao PDR to track movements of 81 individual fish representing 12 different species from June 2022 through March 2024. Upstream movement by Pangasius conchop...

Global freshwater biodiversity is declining dramatically, and meeting the challenges of this crisis requires bold goals and the mobilisation of substantial resources. While the reasons are varied, investments in both research and conservation of freshwater biodiversity lag far behind those in the terrestrial and marine realms. Inspired by a global consultation, we identify 15 pressing priority needs, grouped into five research...

Despite their economic and ecological importance, migratory fishes of the Lower Mekong Basin (LMB) remain understudied, which hampers effective management to sustain valuable fisheries and address serious threats such as habitat degradation, development and overharvest. From a list of potential knowledge needs, a group of fisheries professionals most frequently identified six top priorities for managing migratory fishes in Cam...

Climate warming has yielded earlier ice break‐up dates in recent decades for lakes leading to water temperature increases, altered habitat, and both increases and decreases to ecosystem productivity. Within lakes, the effect of climate warming on secondary production in littoral and pelagic habitats remains unclear. The intersection of changing habitat productivity and warming water temperatures on salmonids is important for u...

Freshwater ecosystems are among the most diverse and dynamic ecosystems on Earth. At the same time, they are among the most threatened ecosystems but remain underrepresented in biodiversity research and conservation efforts. The rate of decline of vertebrate populations is much higher in freshwaters than in terrestrial or marine realms. Freshwater megafauna (i.e., freshwater animals that can reach a body mass ≥30 kg) are intri...

Recreational angling has been implicated in population declines of some marine and freshwater fish, but this activity is rarely considered as a threat or even halted when endangered species are targeted. Indeed, in some cases, anglers are drawn to fish for rare or endangered species. Conservation‐oriented behaviours such as catch‐and‐release are often practiced voluntarily due to the ethics of anglers, yet even in these cases,...

Aim In light of the current biodiversity crisis, there is a need to identify and protect species at greatest risk of extinction. Ecological theory and global‐scale analyses of bird and mammal faunas suggest that small‐bodied species are less vulnerable to extinction, yet this hypothesis remains untested for the largest group of vertebrates, fish. Here, we compare body‐size distributions of freshwater and marine fishes under di...