By a thread: mist net thread thickness influences bat capture success

Abstract The specific ecological characteristics of the species mean that most capture methods are selective, giving rise to sampling bias. Despite their selectivity, mist nets are the most widespread method for bat capture. This research aimed to test the efficiency of ultrathin mist nets compared to regular nets used to capture bats. Sampling was conducted monthly from December 2022 to August 2023 at Pico do Jabre, Serra do Teixeira National Park, Paraíba, Brazil. The bats were captured using regular and ultrathin mist nets with 0.30 mm and 0.09 mm strands, respectively. Differences in the richness, abundance, and composition of the taxocenosis were analyzed according to the type of net used to capture them. A total of 384 individuals from 21 species, 18 genera, and four families were seen. Only ten species and 71 individuals were recorded in regular mist nets, while 21 species and 313 individuals were recorded in ultrathin nets. The number of captures and the richness recorded over the months of sampling were significantly higher in the ultrathin nets. If sampling continues, the maximum extrapolation estimates an increase of up to five species for ultrathin and one more species for regular mist nets. β-diversity points to the nested component responsible for the dissimilarity between mist net types. The ordination analysis revealed the presence of two groups formed by the bat assemblages captured. It was possible to observe that ultrathin nets proved more efficient, recording species that go unnoticed in many mist net surveys.