We have now officially concluded the first field season!! These months have passed in the blink of an eye. We have spent our time driving around the stunning landscapes of North Wales to collect environmental data and faecal samples at each bat roost. We have also installed recorders and cameras under where the bats were resting during the day so that we could monitor their behaviour for the following months.
We did not lack adventure – occasionally we had to climb ladders or silently crawl in dark attics while collecting faecal samples under the dim red light of our torches so that we did not scare the bats. During our brief visits inside the maternity roosts, we had a chance to witness the important stages of the bats’ breeding cycle. First, fluffy and round pregnant females in May, then tiny pups clinging to their mothers in July. Since then, the pups have learnt to fly and have become independent.
Now, the adults are mating again and slowly starting to hibernate. The females will store the sperm throughout the winter and will then become pregnant again in the following spring.
While the bats wait for winter to pass in their hibernation roosts, we will also stay indoors in our lab at the University of Chester, where we will work to process faecal samples and analyse footage and recordings. The season has been a success, so we have a lot of data analysis ahead of us! We have now collected 300 faecal samples and 40 urine samples and almost 300 hours of footage and ultrasound recordings. We have also collected over 20 days and nights of environmental data – light and noise pollution – for each of the ten roosts that we are monitoring.
So, what will we analyse?
We are in the process of detecting and quantifying cortisol, which is considered a ‘stress hormone’ in bats, so that we can then determine if bats in some roosts are more stressed than in others. Since we know that many bat species avoid bright and noisy areas when they look for prey at night, by pairing noise and light levels at the roost entrance with cortisol, we will then be able to determine whether light and noise pollution are indeed causes of stress to the bats. We will also use our footage and recordings to discover what the bats do during the day at the maternity roosts, how they communicate with each other, and when they decide to leave the roost each night to find prey.
We will then be able to see if bats at roosts with more light or noise pollution behave differently, and whether this altered behaviour might indicate stress. We hope that this research will help us to understand what we can do to improve the welfare of our bats.
Now that the first field season is complete, we would like to thank the incredible people that continue to take care of bat roosts at their property and have enthusiastically welcomed us and our research, as well as the fantastic volunteers that gave up some of their time to accompany us on field trips. We also thank the Vincent Wildlife Trust and Natural Resources Wales for their continuous support. We are now ready to dive into the many hours of video recordings and lab work needed to analyse our data until we can see the bats again in the next field season.
Very very interesting!
Amazing