This dataset contains information on the abundance of Mauritia flexuosa sampled in palm swamps managed by the communities of Veinte de Enero and Parinari in Loreto, Peru. Fieldwork was undertaken in August and September 2022 and in August 2023. The data includes abundance data from established 40 forest plots, each 20 m × 100 m, with 5 to 13 plots per management area to quantify the ecological health of each site. In each plot, all individuals of M. flexuosa ≥0.4 m tall were counted and classified into three size classes: short saplings (0.4-1.49 m total height), tall saplings (≥1.5 m total height and without stem or with stem height <1.3 m), and pole stems (≥4 m total height and with stem height ≥1.3 m). For each pole stem, life stage as juvenile (<15 m total height), subadult (≥15 m total height without flowers or fruits), or male/female adult (≥15 m total height with inflorescences or infructescences) was recorded. Sex, the number of racemes with fruits for each female adult individual, and peat thickness were also measured. In this dataset, M. flexuosa populations were assessed to see if they can recover following the introduction of climbing instead of felling the palms for fruit harvesting. The dataset was collected in collaboration with the Instituto de Investigaciones de la Amazonia Peruana (IIAP), the Wildlife Conservation Society (WCS), and the Servicio Nacional de Áreas Naturales Protegidas del Perú (SERNANP). This work was supported by the Natural Environment Research Council (Grants NE/V018760/1 and NE/V018760/2). Full details about this dataset can be found at https://doi.org/10.5285/6d116530-2c6a-4f28-8d42-65100a582ca1
