The influence of local and regional factors on the diversity, structure, and function of West African bat communities (Chiroptera) Biodiversity and Global Change (BIOLOG), BIOTA West Africa, Subproject W09 Fahr, J.1; Ebigbo, N. M. 1; Djossa, B.2; Schmid, S.1; Soer, K.1; Voglozin, A.2; Sinsin, B.2 and Kalko, E.K.V. 1 1
Department of Experimental Ecology (Bio 3), Univ. Ulm, Albert-Einstein Allee 11, 89069 Ulm, Germany 2
Faculté des Sciences Agronomiques, Université d'Abomey-Calavi, 01 BP 526, Cotonou, Benin
[email protected]; http://www.biologie.uni-ulm.de/bio3
Key words
community ecology, habitat heterogeneity, distribution patterns, seed dispersal, vegetation dynamics
Abstract The biodiversity of West African bats was studied on the local and regional scale as well as the role of bats for ecosystem functioning. Our results refute the common assumption of impoverished African bat communities. Instead, we documented highly diverse patterns both for local assemblages and regional species pools. These results contribute to the delimitation of priority areas for conservation and form the indispensable base line against which we will be assessing the effects of human land use along disturbance gradients. Results Our analysis of regional diversity patterns revealed several biodiversity hot spots within West Africa. Habitat heterogeneity seems to be the underlying factor driving species richness of bats in West Africa, with topographical complexity and heterogeneous vegetation zones as the most important causes. For the 1st time, we have developed and applied a standardized sampling approach that allows the direct comparison of bat assemblages along environmental gradients and between areas of different land use [8,9]. Our analyses of bat assemblages in 2 fairly undisturbed habitats revealed by far the highest biodiversity of bats recorded from any region in Africa [2]. Our ongoing studies on the taxonomy of West African bats lead to the revision of several genera and species groups, including the description of taxa new to science [1,7,11]. Genetic analyses conducted in collaboration with the Univ. Erlangen, Magdeburg and Warszawa reveal an astonishing genetic diversity and point to a large number of cryptic species. Initial results of the 1st biodiversity assessment of bats in 2 classified forests of Benin included the 1st record of 5 species for the country. Ongoing studies assess the influence of different land use practices on bat assemblages. We participated in rapid assessment programs to evaluate priority areas for conservation highlighted during an international workshop [6]. These data are being used to delimit areas in the region currently being explored for iron ore and subsequent open cast mining [4,5]. We participate in the 1st Global Mammal Assessment organized by IUCN and CI. Our contribution to the handbook "Mammals of Africa" [3] will feed into this landmark initiative. We show that flying foxes play a major role in the regeneration of trees that are dominant
176
and characteristic of forest islands in the Guinea Zone. The abundance of flying foxes depends on the local density and diversity of fruiting and flowering plant species. References 1. Beaucournu, J.-C. & Fahr, J., Senckenbergiana biol., 2003, 82, 157-162. 2. Fahr, J., Bat Research News, 2001, 42, 98. 3. Fahr, J., 37 chapters, in: The Mammals of Africa, in press, Elsevier & Academic, Amsterdam & London. 4. Fahr, J. and Ebigbo, N. M., Acta Chiropterologica, 2003, 5, 125-141. 5. Fahr, J. and Ebigbo, N. M., pp. 103-118 in: RAP Survey, Socio-economic Threats and Opportunities Assessment, and Initial Biodiversity Action Plan for the Pic de Fon Classified Forest, Guinea, 2003, Conservation International, Washington, DC. 6. Fahr, J. et al., pp. 24-25, Biodiversity Connections from Guinea to Togo, 2001, Conservation International, Washington, DC. 7. Fahr, J., Vierhaus, H., Hutterer, R. and Kock, D., Myotis, 2002, 40, 95-126. 8. Kalko, E. K. V., pp. 13-43, Tropical Biodiversity and Systematics, 1997, Zool. Forschungsinst. Museum A. Koenig, Bonn. 9. Kalko, E. K. V., Zoology, 1998, 101, 281-297. 10. Kalko, E. K. V., Handley jr., C. O. and Handley, D., pp. 503-553, in: Long-Term Studies in Vertebrate Communities, 1996, Academic, Los Angeles. 11. Kock, D., Barnett, L., Fahr, J. and Emms, C., Acta Chiropterologica, 2002, 4, 77-97. 12. Meyer, C. F. J., Schwarz, C. J. and Fahr, J. Trop. Ecol., in press. 13. Schnitzler, H.-U. and Kalko, E. K. V., BioScience, 2001, 51, 557-569. Supported by the BIOLOG program of the German Federal Ministry of Education and Research, project ID: 01 LC 0017 (BIOTA West Africa W09); run duration: Jan. 2000 – Dec. 2003, project leaders: Prof. Dr. E. Kalko & J. Fahr:
[email protected]
Fig. 1: Regional pattern of bat species (n=121) richness in West Africa on a 1 x 1 degree grid. Numbers represent species number for the respective grid square (plotted with WORLDMAP, © P. Williams).
177
Sponsored by the
Sustainable use and conservation of biological diversity A challenge for society
Symposium Report Part A
International Symposium 1 – 4 December 2003 Berlin
Symposium Steering Group: Akhtar-Schuster, Mariam / Hamburg Berendsohn, Walter / Berlin Boutros, Minnattallah / Würzburg Denich, Manfred / Bonn Dziedzioch, Cornelia / Regensburg Henle, Klaus / Leipzig Höynck, Sabine / Köln Jürgens, Norbert / Hamburg Kirk, Michael / Marburg Köhler, Jörn / Bonn Michling, Gerhard / Bonn Plän, Thomas / Regensburg Quintern, Lothar / Bonn Reinhold-Hurek, Barbara / Bremen Rieland, Martin / Bonn Roth, Susanne / Bonn Türkay, Michael / Frankfurt Wüstemeyer, Arndt / Bonn
Event organizer: PT-DLR Umweltforschung Projektträger des BMBF Godesberger Allee 119 D-53175 Bonn Tel.: ++49 228 8199611 Fax: ++49 228 8199640 Email:
[email protected] web: www.biolog-online.info
Event logistic: Poltmann, Heidi / Berlin Roth, Susanne / Bonn
Supporting team: Ahrens, Inga / Bonn Cosar, Meltem / Bonn Friedrich, Frauke / Bremen Kirchhoff, Agnes / Berlin Kugelstadt, Christine / Gießen Maggetti, Claudia / Köln Oetje, Janina / Bremen Oehlschlaeger, Susanne / Berlin Poles, Sonja / Bonn Rehbein, Marcia / Lohmar Rosenberg, Denise / Köln Students of FU Berlin Weiss, Ingeborg / Bonn Wessling, Barbara / Bonn
Layout: Poltmann, Heidi / Berlin
ISBN 3-00-012577-9