Rwanda’s inland fish fauna is small but distinctive, shaped by the country’s high-elevation rift-valley setting and the hydrology linking Lake Kivu to the Kagera/Akagera system, and our knowledge rests on a century of scattered surveys, a pivotal synthesis at the turn of the millennium, and new digitization efforts that finally make specimens discoverable. The most comprehensive baseline remains the annotated checklist by De Vos, Snoeks and Thys van den Audenaerde, which tallied about 82 species in 12 families from Rwandan waters, with cichlids (~37 spp.) far outnumbering cyprinids, mormyrids and mochokid catfishes; notably, at least a dozen of the species on that list were present because of human introductions for fisheries and aquaculture. 

Within Rwanda, Lake Kivu is the headline system: by African Great Lakes standards it is species-poor—roughly 28–29 species, about half of them endemic haplochromine cichlids—yet it supplies the bulk of the country’s wild-caught fish and underpins local livelihoods along both the Rwandan and Congolese shores. Much of the modern fishery there is built on introduced species, especially the pelagic Tanganyika sardine (Limnothrissa miodon), brought from Lake Tanganyika in the late 1950s (1959) to fill an empty plankton-feeding niche; together with tilapiines added earlier and later (e.g., Oreochromis macrochir, Coptodon rendalli, O. niloticus), these introductions transformed the lake’s trophic dynamics and catch composition. Over time, hydroacoustic monitoring and stock assessments have documented how Limnothrissa became the dominant fishery target (the locally famed sambaza/isambaza), while researchers have also tracked ecosystem responses, including zooplankton shifts following the sardine’s establishment. 

Outside Kivu, the Kagera/Akagera drainage hosts a modest riverine fauna with several regionally restricted cyprinids and mochokids; among the fishes of highest conservation concern are two Rwandan endemics in Labeobarbus—Rwandese carp Labeobarbus platystomus (Critically Endangered) and L. ruandae (Near Threatened)—and the upside-down catfish Synodontis ruandae (Vulnerable), a Kagera-system species named from Rwandan material; all three suffer primarily from habitat loss, sedimentation and riparian degradation. 

Historically, fish collecting in Rwanda followed colonial-era natural history patterns—specimens and descriptions tied to expeditions moving between the Albertine Rift and Victoria Basin, with many types and vouchers housed abroad—then broadened with post-independence surveys around Kivu and the upper Akagera, culminating in the 2001 checklist that reconciled historical literature, museum material and modern field data, including the full arc of stocking/introductions that began in the 1950s. 

In the past few years, there has been a visible revival of in-country sampling and training, notably Nyungwe National Park field courses and surveys in 2021 and 2022 that targeted cold, fast headwaters and the Kamiranzovu drainage to Kivu; these efforts have clarified where fish do and don’t occur in high-elevation streams and built local expertise. Importantly for documentation, Rwanda now has a national Rwanda Biodiversity Specimen Portal (Symbiota-based) that publishes collection profiles and occurrence data across taxa; as of today, the Fish – CoEB Natural History Museum (UR-NHM-Fi) collection shows 189 cataloged specimen records (63% identified to species), representing 7 families, 11 genera and 16 named species—a small but growing digitized foundation that complements legacy holdings abroad. Rwanda Biodiversity On the ecological side, contemporary studies emphasize how Kivu’s relatively low habitat heterogeneity in the littoral zone shapes the distribution of its native species, and they also underscore how introduced tilapias and the sardine have restructured both fisheries and pelagic food webs—facts that need to be integrated into conservation and management.

Looking ahead, priority work for Rwanda’s fish conservation falls into several connected tracks. First, baseline consolidation: continue digitizing and barcoding existing lots, finish georeferencing and imaging, and repatriate data for historic Rwandan specimens held in regional and European museums so that occurrence maps and Red List assessments rest on complete evidence. (The current portal metrics make clear how much room there is to expand coverage.) 

Second, targeted surveys and monitoring in under-sampled reaches of the upper Kagera/Akagera, Burera–Ruhondo and other satellite lakes, and high-gradient Nyungwe tributaries, combining standard nets with eDNA to detect rare Labeobarbus and mochokids and to separate true absences from sampling gaps.

Third, threat mitigation in critical catchments: riparian restoration to curb sediment and agrochemical runoff, protection and reconnection of wetland margins used by small cyprinids and mochokids, and community co-management to reduce destructive gears—actions that directly address the drivers listed for L. platystomus, L. ruandae and S. ruandae. 

If Rwanda can pair its growing digital infrastructure and field capacity with catchment-scale habitat protection and a precautionary approach to Kivu’s industrial and fishery uses, it can secure both the unique endemic elements of its fauna and the lake-based food security that millions rely on—turning a once-fragmentary record into a living, adaptive conservation program.