Abundance of Mauritia flexuosa from managed palm swamp sites in Loreto, Peru, 2022-2023

Location of each corner of the plot was recorded using a handheld GPS. Fieldwork was undertaken in August and September 2022 and August 2023. The census was carried out before fruit harvesting, except in San Juan, where fruit harvesting had begun a few days earlier. In each plot, we counted all individuals of M. flexuosa ≥0.4 m tall and classified them 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). All seedlings <0.4 m were counted in a subplot of 5 m × 100 m. For each pole stem, we recorded the 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). The sex of each adult was assessed by observing reproductive structures either on the palms using binoculars or on the ground around the base of the stem. We counted the number of racemes with fruits for each female adult individual. Peat thickness was measured in the centre of each plot using a stick. Peat was identified in the field as a substrate consisting of predominantly wet, partially decomposed organic matter of mid to dark brown colour and at least 30 cm thick. Total height of saplings was estimated using a stick with marks at 0.4 and 1.5 m, while the total height of pole stems was measured using a Suunto clinometer. Binoculars (Bushnell 40X60) were used to determine the sex of adult palms in the field. A protocol to identify the different palm sizes was developed to ensure consistency in data collection among field team members. Sites were selected with local community members implementing the management plans and were checked against Landsat imagery in the field.