Data collection in situ
Sample sites were selected based on location (basimontane and premontane levels) and access. All sample sites are located in the Caquetá Department in the municipalities of Belén de los Andaquíes, Florencia, and Morelia, between 200 and 1500 m a.s.l. (Figure 2, Table 1). Twelve sites (four sites at the basimontane level and eight at the premontane level) were sampled during the falling water season in each of eight years (2013, 2015-2019, 2021, and 2022). However, three sites were not sampled in 2019 due to access restriction because of weather conditions. In total, data represent 91 sample events.
Fish were sampled using SAMUS725M electrofishing equipment, along a 100 m stretch in each of the sample sites. This sampling methodology follows the standardized sampling technique of Maldonado-Ocampo et al. (2005) for subsequent data comparisons. Fish were euthanized with clove oil and fixed in a 10% formaldehyde solution. Prior to species taxonomic identifications, specimen vouchers were transferred for preservation in a 75% ethanol solution. All the fish specimens were deposited in the Ichthyological Collection of the Colombian Amazon (CIACOL ) at the Amazonian Scientific Research Institute (SINCHI) in Leticia, Amazonas, Colombia (https://sinchi.org.co/ciacol).