Acoustic analysis of bat species of the genera hypsugo, pipistrellus and miniopterus in türkiye

There are 40 bat species identified in Türkiye to date. Of these, 32 species belong to the Vespertilionidae family. Bats can be studied through direct observation, and in recent years, they have also been effectively examined using acoustic methods. The use of ultrasonic detectors to acoustically study bats is becoming increasingly common in Turkey, mirroring a global trend. In this study, the analysis of echolocation calls obtained via ultrasonic detectors was conducted for a total of seven species of bats found in Türkiye: Hypsugo savii, Miniopterus pallidus, Miniopterus schreibersii, Pipistrellus kuhlii, Pipistrellus nathusii, Pipistrellus pipistrellus, and Pipistrellus pygmaeus. The study's objectives include identifying differences in the locations where species calls were recorded and classifying the species using two distinct analysis methods, followed by a comparison of these methods. As a result of the analysis of 54,196 calls obtained from 34 locations in total, 2,821 calls belonging to these species were evaluated. Independent Samples T-Test, ANOVA, and Welch's Test were applied to determine if there were a significant difference in calls for each species across locations. For species classification, multinomial logistic regression (MLR) analysis and Eigensound analysis, which is based on geometric morphometrics and using the shape of the sound, were performed. Before conducting the MLR analysis, the number of independent variables was reduced using Principal Component Analysis (PCA) to eliminate multicollinearity issues among the variables. The analysis of variance revealed that the species exhibited significant differences across locations (p<0.05). The accuracy rate of the MLR analysis was calculated as 93.5%, and these findings demonstrated consistency with the results obtained from the Eigensound analysis. It was determined that the calls of P. kuhlii and P. nathusii largely overlapped, and that M. pallidus and M. schreibersii exhibited similar echolocation call structures. Conversely, high success rates were achieved in classifying the species H. savii, M. schreibersii, P. pipistrellus, and P. pygmaeus.