Field respirometry in a wild maternity colony of Bechstein's bats (Myotis bechsteinii) indicates higher metabolic costs above rather than below the thermoneutral zone.

In a warming world, it is crucial to understand how rising temperature affects the physiology of organisms. To investigate the effect of a warming environment on the metabolism of heterothermic bats during the costly lactation period, we characterised metabolic rates in relation to roost temperature, the bats' thermoregulatory state (normothermia or torpor), time of day and age of juveniles. In a field experiment, we heated the communal roosts of a wild colony of Bechstein's bats (Myotis bechsteinii) every other day while measuring metabolic rates using flow-through respirometry.

Optimally warm roost temperatures during lactation do not improve body condition in a long-lived bat.

Lactation is the most energetically demanding time in the life of female mammals. To maximize lifetime reproductive success, females of long-lived species, such as bats, face a trade-off between investing in current and future reproduction. However, it is unclear whether global warming could influence this trade-off through shifts in the energy budget: warmer temperatures may reduce thermoregulatory costs, leaving mothers with more energy available for maternal care or for improving their own body condition (BC), which may increase survival and ensure future reproduction.

Artificially raised roost temperatures lead to larger body sizes in wild bats.

Climate warming has major consequences for animal populations, as ambient temperature profoundly influences all organisms' physiology, behavior, or both. Body size in many organisms has been found to change with increased ambient temperatures due to influences on metabolism and/or access to resources. Changes in body size, in turn, can affect the dynamics and persistence of populations.

Urban affinity and its associated traits: A global analysis of bats.

Urbanization is a major contributor to the loss of biodiversity. Its rapid progress is mostly at the expense of natural ecosystems and the species inhabiting them. While some species can adjust quickly and thrive in cities, many others cannot.