Modelling, mapping and monitoring woodland bats
Habitat suitability modelling for Bechstein’s bat and the effect of an acoustic lure on woodland bats.
It is important to investigate and use a range of available tools in conservation, as a species’ survival
is often dependent on a number of interlinking factors (Poiani et al., 2000). Mapping the spatial
distribution of vulnerable species is important for their conservation and can be done using a
technique called habitat suitability modelling. A tool increasingly used in this field is maximum
entropy modelling (MaxEnt); a type of “presence-only” habitat suitability modelling that allows
spatial predictions to be generated without the need for absence data- useful when studying bats
(Razgour, Hamner & Jones, 2011; Phillips, Anderson & Schapire, 2006). I used MaxEnt to model
habitat suitability for M. bechsteinii in Britain and found that the species is limited to a southern
distribution by habitat and climatic variables. The models produced were validated using new
records for the species and therefore can be used to target future surveys in predicted suitable
areas. It is also important to investigate new methods for monitoring and assessing species
populations on a more local scale. As part of my thesis, I also investigated an acoustic lure (the
Sussex AutoBat) as a method for monitoring bats in woodlands (Hill & Greenaway, 2005). I found
that the lure was successful in increasing activity and captures of bats; and species differentially
respond to different synthesized call playbacks. The lure is therefore a useful tool for studying bats
and should be used as part of a carefully considered integrative approach to woodland monitoring,
along with techniques such as acoustic monitoring.