Hourly activity patterns of the insectivorous bat assemblage in the urban-rural landscape of Lima, Peru

Circadian rhythms of bats are simultaneously influenced by both abiotic and biotic factors that vary across different landscapes. Since cities modify environmental conditions in which bats forage and roost, their temporal activity can be altered. Based on acoustic surveys, we described hourly activity patterns of eight aerial insectivorous bat species in an urban-rural landscape of Lima, Peru. We also explored whether bats show temporal partitioning at the assemblage level and, for three common species, if activity patterns change between landscape units (urban and rural areas) or moonlight intensity (dark and bright nights). At the assemblage level, bats displayed high temporal overlap, especially in rural areas. At the species level, Mormopterus kalinowskii and Tadarida brasiliensis displayed bimodal patterns at both landscape units, and Promops davisoni showed an almost uniform pattern or bimodal pattern at urban and rural sites, respectively. In rural areas, other bat species exhibited either unimodal patterns (Nyctinomops laticaudatus, N. aurispinosus, N. macrotis, and Tomopeas ravus) or a bimodal pattern (Myotis). Moonlight intensity had little influence on activity periods of most bat species. Our study provides valuable information for sampling designs and future studies on activity patterns focused on coexistence among insectivorous bat species in arid landscapes.

Automated summary

We studied the hourly activity patterns of eight bat species in an urban-rural landscape in Lima, Peru, using acoustic surveys. The bats showed high temporal overlap at the assemblage level, particularly in rural areas. At the species level, some species displayed bimodal patterns in both urban and rural areas, while others showed unimodal or bimodal patterns depending on the landscape unit. Moonlight intensity had little influence on most bat species' activity periods.