Biology and Conservation of Threatened Migratory Bats Pipistrellus nathusii and Myotis dasycneme

Results of an international seminar held at the NABU Academy Gut Sunder, Germany,  2-3 December 1998

An international seminar was held at the NABU Academy Gut Sunder, Germany, 2-3 December 1998, to present an overview of the status of P. nathusii and M.dasycneme and to discuss the demands for species conservation actions. This paper presents a summary of the seminar.

Action 1: Collection and evaluation of existing data

An urgent task in bat conservation is the centralisation and international co-ordination of the available data. Data of ringing, roost and habitat observations should be combined into a single databank. The data can be analysed and discussed with support of a geographical information system.

Action 2: International census

Parallel to step 1 an international observer-network should be established to carry out a Europe-wide census. The objectives of the census are:

• assessment of the populations of Nathusius's pipistrelle in its european range.
• identification of its mating, hibernation and maternity areas as well as preferred resting (transitory) areas during migration.
• investigation of the migration routes as well as migration areas.

The census should in principle cover the entire territory of the species in Europe. Where such is not achievable, the census can take place in representative sample areas.

In each country, a national co-ordinator should feel responsible for the collection and evaluation of the data. In larger countries or where high populations densities occur, regional co-workers should be established.

Result of the nationwide census should be published on a national level as soon as possible (e.g. EUROBATS National Reports). Furthermore, the data of the census should be supplied to an international co-ordinator for summarizing overviews and comparative analysises of the data of all countries.

A certain amount of formal and methodical agreement (e.g. netting, ringing, bat-detector, box monitoring among others), is necessary in order to guarantee the comparability of the data such as the number of the occupied roosts, maternity, mating and hibernation roosts. As far as possible additional data on population biology, reproduction success, colony-size, etc. should also be assessed.

To be successful, the census should be limited in time. In addition its success is dependent on the organization and management of the census data.

The tasks of a co-ordinator probably require the position to be housed with an institution with the necessary technical competence and equipment.

Successful performance of the census will only be possible when adequate financial resources are made available to participating NGOs, bat workers and scientists co-ordinating the work on the European as well as the national and regional level. Without additional financial support (e.g. for training and equipment) especially for the scientists and conservationists of the Central and Eastern European countries the census will fail in its objectives.

Action 3: Research

Partially based on the investigations suggested in actions 1 and 2 an international research project should be directed to answering the following questions:

• Which landscape-ecological parameters mark the maternity-areas and wintering areas of Nathusius's pipistrelle?
• Where are the mating, resting and wintering areas and what are the characteristics that identify these sites?
• How does the species spend wintertime?
• Which factors determine the seasonal migration?
• Which kinds of interactions between human activities and Nathusius's pipistrelle occur and how does the human impact influence the populations?

A concept for the methodology for this project is already being developed and was discussed in the seminar.

Action 4: Report, recommendations and guidelines

At the end of the census and the complementary population-biological examination a detailed report should be produced that;

• outlines the actions that have taken to conserve and manage the populations and habitats of Nathusius's pipistrelle,
• describes the areas and landscapes that are key stones for the mating, hibernation, maternity and migration behaviour and should be protected as nature reserves as part of a Europe-wide nature protection system (e.g. NATURA 2000-network or comparable systems),
• defines the priorities for further research-projects and monitoring.

As a result of this program a very exact focus of the status and situation of Nathusius's pipistrelle in Europe might be expected. For the first time the project would give the possibilty to identify and to protect the transboundary habitats of Nathusius's pipistrelle in Europe. This instrument could be developed as a handbook for the planning-authorities and would help to justify the measures which have to be taken to guarantee the survival of this unique European bat species.

Action 1. Ad hoc Census

In contrast to the Nathusius's pipistrelle only relatively few naturalists are studying the pond bat up to now. Therefore an international co-ordinated census has to be the first step to produce a good basis for further research.

Because of the considerable deficits of knowledge, the status and level of threat of the pond bat is not clear. We may, however, assume populations to be present in regions where no assessment has been carried out yet. It must be the primary goal of an internationally co-ordinated nature conservation programme for the pond bat to close the existing knowledge-gaps as quick as possible, by using simple and standardized methods, that are applicable equally in, e.g., Germany, France and Kazakhstan. Detailed research programmes could at this stage be counter productive. The most urgent task consists of the establishment of a centre from which initiatives to develop an international network of observers as well as the implementation of a first international census are co-ordinated.

Actions 1 and 2 which have already been developed in the section dealing with Nathusius's pipistrelle can in principle be transferred to the pond bat. Because habitat-utilization of the pond bat, as far as is known at this stage, shows a distinct relationship to wetland habitats, the observation network could at first focus on the European river systems as well as on lake and wetlands areas of the lowland. In view of the lack of knowledge regarding the distribution and the status of populations of the pond bat it appears advisably to start as quickly as possible with a short-term census directed at such 'wetland habitats'. A more general and detailed and therefore more time consuming large-scale census could be organized as a follow up.

Action 2. Complementary action

Complemantary to action 1 research is necessary to investigate the essential aspects of pond bat biology.

The main objectives of a conservation research programme should be:

• Assess the population status and trends in Europe.
• Identify and protect (potential) pond bat roosts using appropriate methods.
• Educate responible personal and organize and finance survey work.
• Identify (potential) mating roost areas.
• Identify (potential) foraging habitats, key flight paths and migrating routes, and protect and manage a network of core habitats for the pond bat, including summer roosts and hibernicula.
• Co-ordinate and prioritise scentific research on pond bat ecology throughout its european range.

The realization of a research project as sketched above, as well as the implementation of an action plan is only feasable when financial resources are made available to organisations performing bat survey work and research. Especially for the bat conservation in the Central and Eastern European countries financial support is urgently needed.

Authors: Tony Hutson (Bat Conservation Trust, London/UK), Herman Limpens (Wageningen/NL) & Ralf Schulte (NABU-Akademie Gut Sunder/D)

Weiterführende Links

The Agreement on the Conservation of Bats in Europe (Eurobats) - Homepage

Bat Conservation Trust (London) - Homepage

Mrs. Dorothea Barre intends to co-ordinate the census of Nathusius's pipistrelle bat. For further informations contact: Jüdes-Ultraschall, Inh. D. Barre, Schneiderkoppel 21, D-24109 Melsdorf, Tel. ++49 (0) 4340 / 1460, Fax ++49 (0) 4340 / 1417, eMail: barre@juedes-ultraschall.de.

Die Tagungsveranstaltung wurde vom Bundesamt für Naturschutz aus Mitteln des Bundesumweltministeriums gefördert. Die Veranstaltungsinhalte und -ergebnisse geben nicht unbedingt die Meinung des Bundesumweltministeriums, des Bundesamt für Naturschutz oder des Naturschutzbund Deutschland (NABU) wieder.