Woodland bat box study results
The North Bucks Bat Group has been monitoring bat boxes erected at various locations across Buckinghamshire since 2003. We have built up a large database of records which can be interrogated to determine roosting preferences of the different bat species that we find in Bucks. This information is invaluable when putting together detailed studies and has already resulted in two successful MSc studies with a third in preparation.
A Comparison between Acoustic Sampling and Bat Box Inspection as Tools for Assessing and Monitoring Bat Populations in Woodland
A dissertation by Matthew Dodds submitted to The University of Birmingham for the degree of Master of Science, January 2008.
- A field experiment was designed to evaluate the relative efficacy of a frequency division ultrasonic detector with established bat box schemes, to assess and monitor bat populations in woodland
- The methods produced different results in terms of the species encountered and their relative percentages
- Bat boxes proved more effective in recording different species, determining Myotis sp. to species level, recording Plecotus auritus, estimating minimum population sizes and providing a vehicle for more detailed study. Bat detectors proved more effective in recording Pipistrellus pipistrellus and important foraging areas within each woodland
- Plecotus auritus and Myotis nattereri showed a significant preference for boxes that did not receive direct sunlight. Pipistrellus pipistrellus and Pipistrellus pygmaeus showed a significant preference for boxes that did receive direct sunlight
- In flight, Myotis sp. showed a significant preference for areas with > 50% canopy cover. Pipistrellus pipistrellus and Pipistrellus pygmaeus showed a significant preference for areas with < 50% canopy cover
- In appropriate situations, bat boxes represent a more satisfactory and flexible long term monitoring technique than frequency division detector surveys. However both techniques demonstrated certain biases which must be taken into account during analysis of the data they produce.
The full version of this dissertation is available as a PDF file on CD on request from North Bucks Bat Group for an administrative fee of £10.
The Ecology of Choice: Use of Natural and Artificial Roosts by Natterer's Bats Myotis Nattereri in Lowland Coppice Woodland and the Implications for Conservation
A dissertation submitted by Hilary Phillips to the University of Bristol in accordance with the requirements of the degree of MSc in Ecology and Management of the Natural Environment in August 2009.
- This study investigated Natterer's bats' Myotis nattereri use of natural and artificial roosts in an area of lowland coppice woodland in the Aylesbury Vale, Buckinghamshire. Little is known about roost selection in this species and this study provides basic underpinning science in order to inform future management of this species within woodland. Nine female bats were radio-tracked back to 12 day roosts in trees and four in woodcrete boxes. Ten of the tree roosts and all the box roosts were located within the woodland. Tree roosts were in coppiced, standard and pollarded trees. Roost areas with high understorey growth and close proximity to water bodies were favoured. The colony exhibited fission-fusion roosting behaviour which, in conjunction with roost microclimate, probably influenced roost selection.
- Natural and artificial roosts were shown to have differing microclimates. Breeding bats may be prompted to move from the cooler tree roosts to warmer and more humid box roosts during periods of low rainfall and higher temperatures. This behaviour may be related to temperature and humidity in roosts, evaporative water loss in the bats and their changing physiological requirements as pregnancy progresses. The microclimates in box roosts may provide breeding female Natterer's with conditions essential for successful breeding. Further research is required to confirm these findings.
- Areas of stored, neglected or long-rotation coppice woodland provide suitable habitat for woodland specialist bats such as Natterer's. Pressure to bring such areas back into active management for woodfuel could jeopardise these bat populations. A coordinated landscape management approach is needed for lowland coppice woodland, to ensure sufficient patches of woodland habitat of varying age exist to support vulnerable species - such as Natterer's bats - which are reliant on the stored, neglected or long-rotation areas.
MSc Research Project Studying the Relationship between Bat Box Selection and Internal Temperature Regimes of Bat Boxes
To ascertain the influence of internal temperature regimes in the selection of bat boxes in a woodland environment. A dissertation by Hannah Bilston to be submitted in 2011.