Abstract Freshwater ecosystems are among the most threatened globally, yet remain under‐monitored in many regions, particularly in South America. Traditional monitoring approaches, while scientifically rigorous, are often limited by logistical, financial, and institutional constraints. While several citizen science initiatives have advanced freshwater habitat assessment in Europe (e.g., FreshWater Watch) and North America (e.g., EPA's Volunteer Monitoring Program), comparable efforts remain scarce in South America. PreserVamos contributes to filling this regional gap by providing the first large‐scale, standardized citizen‐generated dataset for aquatic ecosystems in Argentina, offering valuable opportunities for integration with global freshwater monitoring databases. “PreserVamos” is a citizen science initiative designed to collect and integrate ecological observations of rivers, lagoons, wetlands, estuaries, and streams throughout Argentina, where participants engage through a mobile application to record semiquantitative ecological indices, environmental conditions, human uses, and wildlife presence. Data are standardized through predefined survey forms and geolocated using mobile GPS. The calculated habitat index is supported by up to 25 complementary variables and a precision score estimating response reliability and is based on published riverine habitat indices for the country. To date, PreserVamos includes over 1200 observations from diverse waterbodies and biogeographic regions in the country, and an additional dataset is included with ~100 observations from other countries. Streams and rivers from the “sierras” (low mountain ranges) were among the most frequently sampled systems ( n = 312) and exhibited the highest ecological quality, with a mean index of 78.38 ± 9.45 (SD) on a scale of 0–100. Mountain streams ( n = 55) also showed high ecological scores, averaging 70.36 (±6.75). In contrast, estuaries ( n = 34) demonstrated lower ecological quality, with a mean index of 61.89 (±15.03). Lowland rivers ( n = 558), the most represented waterbody type, had a moderate mean index of 68.57 (±18.89). Lowland lagoons or lakes ( n = 228) showed lower ecological conditions, with an average score of 62.90 (±14.82). Patagonian forest lakes ( n = 29) had a high mean index of 78.34 (±11.06), while Patagonian Forest rivers ( n = 12) showed moderate conditions at 69.20 (±9.40). Patagonian steppe rivers were only represented by two observations, with a preliminary mean of 74.15 (±9.40). The dataset provides a unique opportunity to analyze spatial and seasonal ecological trends, assess the effectiveness of citizen science in environmental monitoring, and inform ecosystem management. This dataset is published under a Creative Commons Attribution 4.0 International License (CC‐BY 4.0). Users may reuse the dataset with proper citation.
Cochero et al. (Sun,) studied this question.