Pipistrellus pygmaeus, Nursery Roost Monitoring Times

Adjustments for P. pygmaeus Nursery Roost Monitoring Times View in CoL in Response to Climate Change

The use of night vision aids to record bat exit counts ( Andrews and Andrews, 2016; Bat Conservation Trust, 2022 b) enables one person to monitor emergence and would facilitate additional nursery roost counts in weeks 6–8 in years when the probability of an early first peak exit of the P. pygmaeus population is high. Since the P. pygmaeus population trend is linked to environmental changes as possible causes of decline it is necessary to consider the implications of climate change on nursery roost activity and review roost monitoring times. However, the use of integrated air temperature records from January to March offer a simple method for the prediction of years when the first peak exit will be early and enable monitoring of the extent and pace of the effects of climate change on P. pygmaeus .