As they use a variety of habitats, from streams and woodland to gardens, the presence of bats is a useful indicator of how well an area is functioning for wildlife. To put it another way, if your local patch has no bats, then there’s something wrong with it!
In response to declines in bat populations during the past century, all UK bats are now legally protected. Delivering this protection is actually quite difficult, as a particular habitat will not be used continually throughout the year. Bats need places to both rest (roost) and feed, as well as conditions that make them feel comfortable flying between the two (commuting). Protecting roosts in built structures and trees is vital, but it’s only part of the solution. If there are no local habitats producing the right type of insects, or if flight routes are poor, roosts are unlikely to deliver their full potential.
Similar to the bird and bee work, the bat research is looking at how the quality and layout of the urban landscape influences the diversity and abundance of the bat community. This will allow us to address questions such as:
1. Does it matter where a feeding area is located in an urban area?
2. Do connectivity thresholds exist, below which feeding areas are not used?
A juvenile Leisler's bat (Nyctalus leisleri). Photo: Chris Sherlock
This first project will look at the factors influencing the degree to which ponds are used by bats in different parts of the West Midlands. Each species has differing sensitivities to lighting, vegetation cover, roost and insect availability. Survey sites have therefore been selected that contrast in these factors, but also have features that should be attractive to typical urban bats.
Follow this link to see a selection of potential survey sites (ponds) for summer 2009-10. This is a google map, so click on 'hybrid' to see the road names as well as the aerial photograph.
Urban lighting. Photo: Environment Agency 2009
To be able to answer these questions we need to survey a range of sites repeatedly, as bat activity varies with both the weather and season. Surveying generally involves walking a set route around a defined area after dusk, using a bat detector to listen for their distinct echolocation calls and observing flight behaviour.
Surveys are planned for many locations across the West Midlands, so if you want to join in this summer, contact us or have a look at the Birmingham Bat group events calendar.