Ecology and Conservation of Bats in Villages and Towns

Transcription

1 Schriftenreihe fur Landschaftspflege und Naturschutz Heft 77 Ecology and Conservation of Bats in Villages and Towns Results of the scientific part of the testing & development project "Creating a network of roost sites for bat species inhabiting human settlements" Matthias Simon, Sandra HuttenbCigel and Janna Smit-Viergutz in collaboration with Peter Boye Bundesamt fur Naturschutz Bonn - Bad Godesberg 2004

2 Contents 1 Introduction 11 2 Area of Investigation Landform of the Marburg-Biedenkopf district Climate Landuse 15 3 Methods - aims, description and evaluation Introduction Acoustic detection Emergence observation Capture and banding of bats Data compilation of captured bats Radio-tracking Nocturnal observations of behaviour at the roost Use of chemiluminescent light sticks Automatic roost surveillance Temperature measurement in roosts Genetic Investigations of bats Use of Geographical Information Systems (G1S) to analyse the habitat of different bat species Balancing of expense of the recording methods 30 4 State of the registration of bat population numbers before and after the project Common pipistrelle (Pipistrellus pipistrellus [Schreber, 1774]) - 45 khz-type Distribution and abundance within the project area Regional and national distribution and abundance Serotine bat (Eptesicus serotinus [Schreber, 1774]) Distribution and abundance within the project area Regional and national distribution and abundance The greater mouse eared bat (Myotis myotis [Borkhausen, 1797]) Distribution and abundance within the project area Regional and national distribution and abundance Natterer's bat (Myotis nattered [Kuhl, 1817]) Distribution and abundance within the project area Regional and national distribution and abundance Whiskered bat (Myotis mystacinus [Kuhl, 1817]) Distribution and abundance within the project area Regional and national distribution and abundance Common long-eared bat (Plecotus auritus [Linnaeus, 1758]) Distribution and abundance within the project area Regional and national distribution and abundance Grey long-eared bat (Plecotus austriacus [J.B. Fischer, 1829]) Distribution and abundance within the project area 54 5

3 4.7.2 Regional and national distribution and abundance Barbastelle bat (Barbastella barbastellus [Schreber, 1774]) ~ Distribution and abundance within the project area Regional and national distribution and abundance Conservation status of investigated bat species according to Red Lists Summary 59 Requirements of summer roosts for bats Introduction Roost types and categories Common pipistrelle Serotine bat Greater mouse-eared bat Natterer's bat Whiskered bat Common long-eared bat Grey long-eared bat Barbastelle bat Exposition Roost openings Location of roosts in town Age of buildings Upkeep condition of the buildings Height of buildings Material of landing area Roost temperatures Hollow spaces in the facade and behind facade siding Intermediate roof Hollow space in a breezeblock ceiling of a cowshed Gap between two walls made of hollow concrete blocks Attic What are the features of a potential roost? Summary 108 How do bats explore their roosts? Ill 6.1 Introduction Ill 6.2 Swarming of the common pipistrelle at the hibernaculum Ill Investigated hibernacula Seasonal phenology Swarming behaviour at and in the hibernaculum Spatiofunctional correlation between hibernaculum and summer roost (radio-tracking) Experiments in and at the hibernaculum concerning the roost locating ability of the common pipistrelle Invasions Seasonal phenology Nocturnal phenology Invasion sites are in hibernaculum towns and villages 131

4 6.5.4 Experiments concerning the roost locating ability of common pipistrelles at an invasion site - how do invasions happen? Swarming at the summer roost Nocturnal activity of the common pipistrelle at occupied maternity roosts Nocturnal activity of the common pipistrelle at unoccupied maternity roosts Nocturnal activity of the serotine bat at a roost complex Summary 145 Spatiofunctional relationships Introduction Summer roost assemblage (level 1) Common pipistrelle Spatial examination of the roost assemblage Temporal examination of roost switching behaviour The chronological process of roost switching Frequency of roost switching by adult, subadult and juvenile bats in one year Serotine bat Spatial examination of the roost assemblage Temporal examination of roost switching Greater mouse-eared bat Whiskered bat Natterer's bat Barbastelle bat Grey long-eared bat Utilisation of foraging sites (level 2) Common pipistrelle Serotine bat Greater mouse-eared bat Whiskered bat Natterer's bat Barbastelle bat Grey long-eared bat The summer move to another roost (level 3) Common pipistrelle Serotine Bat Greater mouse-eared bat Spatial relationship between summer roost and hibernaculum (level 4) Common pipistrelle Greater Mouse-eared bat Consequences for conservation Summary 189 Population genetics Introduction Basics of population genetics 196 7

5 8.2.1 Mitochondrial DNA Genetic drift and gene flow Materials and methods Results Serotine bat Common pipistrelle Discussion Summary Roost destruction Introduction Roost destruction in the project area Summary How successful is the creation of new roosting opportunities? Introduction Description of roost offer Schedule of establishment of roost offers: at which point of time were potential roosts habitable for bats? Differentiation between new creation, optimisation, preservation, and replacement of roosts Roost types Gable panneling inside with access from outside (category II) Crevice roost under roofing with access from outside (category II) Bat roosting board, single- and double-walled (category I) Crevice roost behind ridge beam (category I) Crevice roost behind slate facade (category I) Crevice roosts in attics (category III) Dormer window with bat fly-in entrance (category IV) Ventilation dormer window out of zinc sheet (category IV) Wooden shutter in gable window with fly-in crevice (category IV) Spatial distribution Control to determine success of newly created potential roosts Usage rate of newly created potential roosts Which bat species use the newly created potential roosts? Temporal perspective of the process of reconnoitring or inhabiting roosts - How fast are potential roosts discovered or inhabited? Which type of newly created potential roost finds most acceptance? Interior panelling with outside access Crevice roosts under roofing with outside access Crevice roosts in attics Final evaluation of newly created and optimised potential roosts Summary Landscape features and distribution Introduction Correlation between occurrence of particular bat species and specific landscape features 233

6 Common pipistrelle Serotine bat Natterer's bat Barbastelle bat Flight routes of different bat species Summary Synopsis Project goals and hypotheses Evaluation of danger to bats Conservation of bats in areas where they have settled Improvement of database for bat conservation Demands on federal, state and local government Acknowledgements References 251