Long-term field studies in bat research: importance for basic and applied research questions in animal behavior

Abstract

Animal species differ considerably in longevity. Among mammals, short-lived species such as shrews have a maximum lifespan of about a year, whereas long-lived species such as whales can live for more than two centuries. Because of their slow pace of life, long-lived species are typically of high conservation concern and of special scientific interest. This applies not only to large mammals such as whales, but also to small-sized bats and mole-rats. To understand the typically complex social behavior of long-lived mammals and protect their threatened populations, field studies that cover substantial parts of a species’ maximum lifespan are required. However, long-term field studies on mammals are an exception because the collection of individualized data requires considerable resources over long time periods in species where individuals can live for decades. Field studies that span decades do not fit well in the current career and funding regime in science. This is unfortunate, as the existing long-term studies on mammals yielded exciting insights into animal behavior and contributed data important for protecting their populations. Here, I present results of long-term field studies on the behavior, demography, and life history of bats, with a particular focus on my long-term studies on wild Bechstein’s bats. I show that long-term studies on individually marked populations are invaluable to understand the social system of bats, investigate the causes and consequences of their extraordinary longevity, and assess their responses to changing environments with the aim to efficiently protect these unique mammals in the face of anthropogenic global change.

Heat over heritability: Increasing body size in response to global warming is not stabilized by genetic effects in Bechstein's bats

“…We investigated a 25‐year dataset (1996–2020) of individually RFID‐tagged wild female Bechstein's bats living in four colonies (BS, GB2, HB and UA) within 15 km of one another that inhabit deciduous forests near the city of Würzburg, Bavaria, Germany (Kerth, 2022; Kerth et al, 2002). Although the composition of tree species and forest management is similar between sites, we added birth year as a random factor in all models and tested the effect of colony ID to account for any remaining spatio‐temporal variance.…”

“Pit-tag” como marca permanente en Myotis chiloensis (Chiroptera: Vespertilionidae) y Tadarida brasiliensis (Chiroptera: Molossidae) en Chile central

“…Contar con un sistema de marcaje efectivo y seguro para los animales ha permitido una mejor comprensión de las dinámicas poblacionales y facilitado el monitoreo a largo plazo en murciélagos (Kerth 2022). Es importante generar estudios de largo plazo sobre los murciélagos en Chile, ya que de las quince especies que actualmente habitan en el país, seis están clasificadas en alguna categoría de conservación que implica algún grado de amenaza (categorías "En Peligro", "Vulnerable", "Casi Amenazada") (MMA 2022).…”

“…En Chile, el número de estudios sobre murciélagos ha aumentado significativamente en los últimos años (e.g., Ossa et al 2020;Rodríguez-San Pedro et al 2020, 2022Chaperon et al 2022;Quiroga et al 2022), pero aún continúa siendo un grupo poco estudiado en comparación con otros grupos zoológicos (Fernández et al 2016). Además, son escasos los estudios específicos que evalúen el efecto o los resultados de la aplicación de métodos de marcaje sobre este grupo de mamíferos (e.g., Puelma-Diez et al 2021).…”

Costs and benefits of solitary living in mammals

“…Being insectivorous means feeding competition does not allow large groups and might thus favour pair or solitary living, which is common in Eulipotyphla (Valomy et al., 2015). For some insectivorous species, being pair‐ or group‐living solitary foragers can be a solution for, for example, insectivorous bats (Kerth, 2022). Large predators such as many bears and most large cats are solitary, maybe as an adaptation to the distribution and size of their prey (Nowak & Wilson, 1999).…”