Chiroptera Personality-A Guide for Assessing Personality Variation in Bats: Ecological, Methodological and...

Consistent between-individual differences, that is, animal personality (AP) is among the fastest-growing topics in behavioural biology, with theoretical and empirical work showing important consequences for ecology, evolution and conservation. Yet bats-the second-largest mammalian order-remain markedly underrepresented despite their functional importance in many ecosystems. We therefore synthesise ecological, methodological and statistical considerations for analysing bat personality while retaining general validity to facilitate transferability to other taxa. Because many bat species exhibit extraordinary life histories and characteristics, we provide structured guidance to design impactful experimental setups, anticipate field-work challenges, unify schemes for annotating recordings and navigate complex analyses associated with repeated measures. These decisions are critical because they determine repeatability, ecological validity and cross-study comparability, and they delimit which statistical models can be robustly fitted under realistic sample sizes and field logistics. We provide a comprehensive statistical protocol both as a schematic overview and as an annotated R script accompanied by dummy data. The workflow covers five main steps expected in a hypothetical personality study: (i) analysis of structural covariates using (G)LMMs, (ii) repeatability analysis to identify consistent behavioural measures, (iii) principal component analysis for dimensionality reduction, (iv) validation of traits via control experiments and (v) modelling links from putative behavioural traits to a focal outcome with ecologically significance. Together, these resources enable researchers to follow, understand and implement the entire procedure and to extrapolate the methodology to their own experiments. By unifying methodological practice for a currently under-represented taxon, we aim to maximise the validity of findings and highlight promising avenues for future studies that establish strong, hypothesis-driven testing paradigms for bat personalities. More broadly, we seek to deepen understanding of personality variation and its consequences in bats specifically and to enhance the comparative value of AP research generally.