Seasonal Activity of Urban Bats Populations in Temperate Climate Zone—A Case Study from Southern Poland

Abstract

Simple Summary Urban green areas are essential for many animals inhabiting cities, including bats. They provide food and shelter, and also facilitate migration. Our aim was to identify bat species inhabiting Planty Park in Cracow and determine how their activity differed depending on the weather and season. We recorded bats’ calls on ultrasonic detectors in 2016 and 2017. In total, 2 of 10 observed species were new for this part of Poland: the Kuhl’s pipistrelle (Pipistrellus kuhlii) and the Savi’s pipistrelle (Hypsugo savii). We divided all species into groups of similar ecology for further analyses. Myotis bats were the least active group. Bats of genera Nyctalus, Eptesicus and Vespertilio were the most active in late summer, similarly to Pipistrellus and Hypsugo, although statistics did not back the outcome for the latter two genera. In spring and early summer, Nyctalus, Eptesicus and Vespertilio bats were more active during warmer nights, while in autumn, they preferred cloudless nights. Interestingly, Pipistrellus and Hypsugo bats decreased their activity at higher temperatures during summer. Our study will lead to a better understanding of bat ecology in urban areas and will contribute to setting urban landscape planning recommendations. Abstract Municipal greenery can mitigate the negative impact of urbanization on biodiversity, including bats, by providing a migration corridor, food base and roosts. Our study aimed to evaluate the species composition and diversity, test the differences in activity between seasons, and identify the atmospheric conditions influencing the bats’ activity in the Planty Park (Cracow). Fieldworks were conducted in 2016 and 2017. We recorded 10 species, two new for this part of Poland: the Kuhl’s pipistrelle (Pipistrellus kuhlii) and the Savi’s pipistrelle (Hypsugo savii). Taxa were divided into three ecological guilds. Myotis group’s activity was insufficient to perform statistical analyses. The activity of Nyctalus, Eptesicus and Vespertilio group peaked in late summer. A similar insignificant trend was observed for Pipistrellus and Hypsugo. Temperature enhanced the activity of Nyctalus, Eptesicus and Vespertilio group in spring and early summer, while cloud cover suppressed their activity in autumn. Temperature also enhanced Pipistrellus and Hypsugo group activity in spring and autumn, but it suppressed their summer activity. Our study is one of the first to investigate temperate urban bats’ phenology and may serve as a preface for further research to introduce detailed urban landscape planning recommendations.