Citizen Science as an Early-Warning System for Non-Native Freshwater Invertebrates in Saudi Arabia
Freshwater ecosystems in Saudi Arabia are increasingly shaped by dams, reservoirs, irrigation networks, and urban water management, yet baseline information on non-native freshwater invertebrates remains extremely limited. This study provides an early-warning assessment of potential introductions by synthesizing publicly available occurrence signals and screening them for geographic consistency and supporting photographic evidence. The records were summarized spatially to identify clustering patterns associated with engineered freshwater habitats and areas of high human activity. The occurrence signals for high-risk freshwater invertebrate taxa were geographically concentrated in urban and peri-urban water bodies in central Saudi Arabia, with repeated observations near managed wadis and reservoirs suggesting plausible human-mediated introduction pathways. Because records derived from citizen-science platforms remain unverified in the absence of voucher specimens or molecular confirmation, they are treated conservatively as early-warning signals rather than confirmed occurrences. These findings identify priority areas for targeted surveillance around reservoirs, irrigation schemes, and recreational waters and recommend proactive screening and early-detection programs to protect freshwater biodiversity and fisheries resources. This study represents the first synthesis framing publicly available occurrence signals as a management-relevant early-warning baseline for non-native freshwater invertebrates in Saudi Arabia.