Bark harvesting: a potential threat for the Grandidier’s baobab Adansonia grandidieri in western Madagascar
Keywords:
Madagascar, baobab de Grandidier, écorce, Menabe, dry tropical forest, Natural resources,Abstract
The Grandidier’s baobab conveys the image of Madagascar worldwide. Locally, these trees have multiple uses; all parts of the plant are exploited by the population. We investigated the patterns of bark harvesting on the Grandidier’s baobab in three districts in the Menabe Region: Mahabo, Manja and Morondava. Following 103 transects of 1km each, we found that 54.0% of the baobab trees had been subject to bark extraction. The mean total area exploited per tree was 3.1 ± 0.2m2. Between April 2013 and January 2014, we also monitored four markets that regularly sell baobab products: Bemanonga, Mahabo, Morondava and Analaiva. Bemanonga revealed to be the largest market for the baobab bark with 21,594 straps and 34,517m of ropes recorded during the observation period. We estimate that some 9800 Grandidier’s baobab trees have been affected by debarking to supply the demands recorded over the ten months monitoring period. If this demand remains constant, all baobab trees in Menabe would be debarked within the next 39 years. Since most baobab trees have been located in hard-to-reach areas and in protected areas, bark extraction may intensify in accessible sites and populations without protected status may disappear locally. This would result in local extinction of the species within a short period. To ensure sustainable management of the Grandidier’s baobab, we recommend enriching the population by planting young baobabs, regulating access to the resources through local management structures and promoting alternatives to baobab ropes.
Résumé
Le baobab de Grandidier est une espèce emblématique de Madagascar. Il évoque la Grande Île dans le monde entier. Dans sa zone d’occurrence, c’est une espèce à usage multiple pour les riverains qui utilisent toutes les parties de ce baobab. La présente étude porte sur l’exploitation de l’écorce du baobab de Grandidier dans la région Menabe, plus particulièrement dans les districts de Mahabo, Manja et de Morondava. Pour estimer l’étendue de l’exploitation des écorces sur les pieds de baobabs, des observations ont été réalisées sur 103 transects de 1 km de long entre avril 2013 et janvier 2014. Pour évaluer l’importance des écorces de baobab pour les riverains, des observations ont été conduites au niveau de quatre marchés de la région dans les villes de Bemanonga, Mahabo, Morondava et Analaiva au cours de la même période. Au total, 21 594 lanières d’écorce et 34 517 m de corde de baobab ont été recensés dans les quatre marchés. La plus importante quantité d’écorce de baobabs commercialisée a été enregistrée à Bemanonga. À partir des données récoltées, il est estimé que près de 9800 pieds de baobabs à écorcer sont nécessaires pour couvrir les besoins des riverains pendant la seule période d’études de 10 mois. Si la demande devait se maintenir à ce niveau, tous les pieds de baobab de la région Menabe, dont la population avait été estimée à environ un million d’individus, seraient écorcés au cours des 39 prochaines années. Comme la plupart des pieds de baobab ont été localisés dans des zones difficiles d’accès et dans les aires protégées, l’extraction des écorces pourrait s’intensifier dans les sites accessibles et les populations qui ne bénéficient d’aucun statut de protection pourraient disparaître localement. Pour assurer la gestion durable du baobab de Grandidier, il est ainsi recommandé de renforcer la population existante par la plantation de jeunes plants, la régulation de l’accès aux ressources par des structures locales de gestion et la promotion d’alternatives aux cordes réalisées avec les écorces de baobab.
References
Antona, M., Biénabe, E. M., Salles, J.-M., Péchard, G., Aubert, S. and Ratsimbarison, R. 2004. Rights transfers in Madagascar biodiversity policies: achievements and significance. Environment and Development Economics 9, 6: 825–847. <https://doi.org/10.1017/S1355770X04001640>
Baum, D. A. 1996. The ecology and conservation of the baobabs of Madagascar. Primate Report 46: 311–327.
Bond, J. 2002. Baobabs. In: Guide to Madagascar, 7th edn. Bradt H. (ed.), pp 40–46. Bradt Publications, Chalfont St. Peter.
Botha, J., Witkowski, E. T. F. and Shackleton, C. M. 2004. The impact of commercial harvesting on Warbugia salutaris (pepper-bark tree) in Mpumalanga, South Africa. Biodiversity & Conservation 13, 9: 1675–1698. <https://doi.org/10.1023/B:BIOC.0000029333.72945.b0>
Brooks, T. M., Mittermeier, R. A., Mittermeier, C. G., da Fonseca, G. A. B., Rylands, A. B. et al. 2002. Habitat loss and extinction in the hotspots of biodiversity. Conservation Biology 16, 4: 909–923. <https://doi.org/10.1046/j.1523-1739.2002.00530.x>
Callmander, M. W., Phillipson, P. B., Schatz, G. E., Andriambololonera, S., Rabarimanarivo, M. et al. 2011. The endemic and non-endemic vascular flora of Madagascar updated. Plant Ecology and Evolution 144, 2: 121–125. <https://doi.org/10.5091/plecevo.2011.513>
Cron, G. V., Karimi, N., Glennon, K. L., Udeh, C., Witkowski, E. T. F., et al. 2016. One African baobab species or two? A re-evaluation of Adansonia kilima. South African Journal of Botany 103: 312. <https://doi.org/10.1016/j.sajb.2016.02.036>
Cuni Sanchez, A., Osborne, P. E. and Haq, N. 2010. Identifying the global potential for baobab tree cultivation using ecological niche modelling. Agroforestry Systems 80, 2: 191–201. <https://doi.org/10.1007/s10457-010-9282-2>
Cunningham, A. 2001. Applied ethnobotany: people, wild plant uses and conservation. Earthscan Publications Ltd., London, UK.
Delvaux, C., Sinsin, B., Darchambeau, F. and Van Damme, P. 2009. Recovery from bark harvesting of 12 medicinal tree species in Benin, West Africa. Journal of Applied Ecology 46, 3: 703–712. <https://doi.org/10.1111/j.1365-2664.2009.01639.x>
Ehrensperger, T., Urech, Z. L., Rehnus, M. and Sorg, J. P. 2013. Fire impact on the woody plant components of dry deciduous forest in Central Menabe, Madagascar. Applied Vegetation Science 16, 4: 619–628. <https://doi.org/10.1111/avsc.12034>
Gaoue, O. G. and Ticktin, T. 2008. Impacts of bark and foliage harvest on Khaya senegalensis (Meliaceae) reproductive performance in Benin. Journal of Applied Ecology 45, 1: 34–40. <https://doi.org/10.1111/j.1365-2664.2007.01381.x>
Garcia, G. and Goodman, S. M. 2003. Hunting of protected animals in the Parc National d'Ankarafantsika, north-western Madagascar. Oryx 37, 1: 115–118. <https://doi.org/10.1017/S0030605303000206>
Gardner, C. J. 2011. IUCN management categories fail to represent new, multiple-use protected areas in Madagascar. Oryx 45, 3: 336–346. <https://doi.org/10.1017/S0030605310001808>
Graf, E., Andriambelo, L. H. and Sorg, J.-P. 2009. Ecological and social issues, availability and uses of four timber tree species in Menabe, Madagascar. Bois et Forêts des Tropiques 302, 4: 33–41. <https://doi.org/10.19182/bft2009.302.a20398>
Greenwood, J. J. D. and Robinson, R. A. 2006. General census methods. In: Ecological Census Techniques. Sutherland, W. J. (ed.), pp 87–183. Cambridge University Press, Cambridge.
Grinand, C., Rakotomalala, F., Gond, V., Vaudry, R., Bernoux, M. and Vieilledent, G. 2013. Estimating deforestation in tropical humid and dry forests in Madagascar from 2000 to 2010 using multi-date Landsat satellite images and the random forests classifier. Remote Sensing of Environment 139: 68–80. <https://doi.org/10.1016/j.rse.2013.07.008>
Hall, P. and Bawa, K., 1993. Methods to assess the impact of the extraction of non-timber tropical forest products on plant populations. Economic Botany 47, 3: 234-247. <https://doi.org/10.1007/BF02862289>
IUCN 2016. The IUCN Red List of Threatened Species 2016. Version 3.1. Available online
Karimi, N., Grover, C. E., Gallagher, J. P., Wendel, J. F., Ané, C. and Baum, D. A. 2019. Reticulate evolution helps explain apparent homoplasy in floral biology and pollination in baobabs (Adansonia; Bombacoideae; Malvaceae). Systematic Biology. <https://doi.org/10.1093/sysbio/syz073/5613901>
Krebs, C. J. (ed.) 1999. Ecological Methodology. Benjamin Cummings, Menlo Park, California.
Kremen, C., Cameron, A., Moilanen, A., Phillips, S. J., Thomas, C. D. et al. 2008. Aligning conservation priorities across taxa in Madagascar with high-resolution planning tools. Science 320, 5873: 222–226. <https://doi.org/10.1126/science.1155193>
Mamilaza, L. E. 2009. Diagnostic de la filière baobab : quelles limites et perspectives ? Cas de Adansonia grandidieri dans la commune de Bemanonga, région du Menabe. Mémoire d’études pour l’obtention du Diplôme d’Etudes Supérieures Spécialisées. Option Développement Local et Gestion de Projet. 63 pp. Faculté de Droit, Economie et de la Sociologie. Département Economie. Université d’Antananarivo.
Marie, C. N., Sibelet, N., Dulcire, M., Rafalimaro, M., Danthu, P. and Carrière, S. M. 2009. Taking into account local practices and indigenous knowledge in an emergency conservation context in Madagascar. Biodiversity and Conservation 18, 10: 2759–2777. <https://doi.org/10.1007/s10531-009-9672-9>
Miles, L., Newton, A. C., DeFries, R. S., Ravilious, C., May, I., et al. 2006. A global overview of the conservation status of tropical dry forests. Journal of Biogeography 33, 3: 491–505. <https://doi.org/10.1111/j.1365-2699.2005.01424.x>
Mukamuri, B. B. and Kozanayi, W. 1999. Institutions surrounding the use of marketed bark products. The case of Berchemia discolor, Adansonia digitata, and Warburgia salutaris. IES Working Paper Number 17. Available at <https://opendocs.ids.ac.uk/opendocs/>
Mutke, J., Sommer, J. H., Kreft, H., Kier, G. and Barthlott, W. 2011. Vascular plant diversity in a changing world: global centres and biome-specific patterns. In: Biodiversity Hotspots—Evolution and Conservation. J. C. Habel and F. Zachos (eds.), pp 83–96. Springer, Berlin, Heidelberg, Germany.
Myers, N., Mittermeier, R. A., Mittermeier, C. G., da Fonseca, G. A. B. and Kent, J. 2000. Biodiversity hotspots for conservation priorities. Nature 403: 853–858. <https://doi.org/10.1038/35002501>
Neudert, R., Ganzhorn, J. U. and Waetzold, F. 2017. Global benefits and local costs—the dilemma of tropical forest conservation: A review of the situation in Madagascar. Environmental Conservation 44, 1: 82–96. <https://doi.org/10.1017/S0376892916000552>
Norscia, I. and Borgognini-Tarli, S. M. 2006. Ethnobotanical reputation of plant species from two forests of Madagascar: A preliminary investigation. South African Journal of Botany 72, 4: 656–660. <https://doi.org/10.1016/j.sajb.2006.04.004>
Perrier de la Bâthie, H. 1924. Sur quelques plantes non cultivées de Madagascar à fruits comestibles ou utiles et sur la possibilité de leur culture. Journal d’Agriculture Traditionnelle et de Botanique Appliquée 38: 652–662. <https://doi.org/10.3406/jatba.1924.4224>
Peters, C. M. 1994. Sustainable harvest of non-timber plant resources in tropical moist forest: an ecological primer. WWF, Washington.
Ramohavelo, D. and Sorg, J.-P. 2008. Using NTFPs to drive rural development without threatening biodiversity? A concrete example concerning four NTFPs in Central Menabe, Madagascar. Tropentag 2008 University of Hohenheim, October 7–9, 2008 Conference on International Research on Food Security, Natural Resource Management and Rural Development.
Randrianandrianina, F. H., Racey, P. A. and Jenkins, R. K. B. 2010. Hunting and consumption of mammals and birds by people in urban areas of western Madagascar. Oryx 44, 3: 411–415. <https://doi.org/10.1017/S003060531000044X>
Scales, I. R. 2012. Lost in translation: conflicting views of deforestation, land use and identity in western Madagascar. The Geographical Journal 178, 1: 67–79. <https://doi.org/10.1111/j.1475-4959.2011.00432.x>
Scales, I. R. 2014. Tourism, conservation and development in Madagascar: moving beyond panaceas? In: Rainforest Tourism, Conservation and Management: Challenges for Sustainable Development. B. Prideaux (ed.), pp 255–256. Earthscan, London.
Schmidt, I. B., Mandle, L., Ticktin, T. and Gaoue, O. G. 2011. What do matrix population models reveal about the sustainability of non-timber forest product harvest? Journal of Applied Ecology 48, 4: 815–826. <https://doi.org/10.1111/j.1365-2664.2011.01999.x>
Schumann, K., Wittig, R., Thiombiano, A., Becker, U. and Hahn, K. 2010. Impact of land-use type and bark and leaf-harvesting on population structure and fruit production of the baobab tree (Adansonia digitata L.) in a semi-arid savanna, West Africa. Forest Ecology and Management 260, 11: 2035–2044. <https://doi.org/10.1016/j.foreco.2010.09.009>
Ticktin, T. 2004. The ecological implications of harvesting non-timber forest products. Journal of Applied Ecology 41, 1: 11–21. <https://doi.org/10.1111/j.1365-2664.2004.00859.x>
Vieilledent, G., Cornu, C., Cuni Sanchez, A., Leong Pock-Tsy, J.-M. and Danthu, P. 2013. Vulnerability of baobab species to climate change and effectiveness of the protected area network in Madagascar: Towards new conservation priorities. Biological Conservation 166: 11–22. <https://doi.org/10.1016/j.biocon.2013.06.007>
Waeber, P. O., Rafanoharana, S., Rasamuel, H. A. and Wilmé, L. 2019. Parks and reserves in Madagascar: managing biodiversity for a sustainable future. [Online First], IntechOpen. <https://doi.org/10.5772/intechopen.85348>
West, P. W. 2009. Tree and Forest Measurement. Springer-Verlag Berlin Heidelberg.
Wickens, G. E. and Lowe, P. 2008. The Baobabs: Pachycauls of Africa, Madagascar and Australia. Springer, The Netherlands.
Wilmé, L., Ravokatra, M., Dolch, R., Schuurman, D., Mathieu, E., et al. 2012. Toponyms for centers of endemism in Madagascar. Madagascar Conservation & Development 7: 30–40. <https://doi.org/10.4314/mcd.v7i1.6>
World Bank. 2014. Poverty Overview. Available at <http://www.worldbank.org/en/topic/poverty/overview>
Zinner, D., Wygoda, C., Razafimanantsoa, L., Rasoloarison, R., Andrianandrasana, H. T., et al. 2013. Analysis of deforestation patterns in the central Menabe, Madagascar, between 1973 and 2010. Regional Environmental Change 14, 1: 157–166. <https://doi.org/10.1007/s10113-013-0475-x>
Downloads
Additional Files
Published
Issue
Section
License
All journal content, except where otherwise noted, is licensed under a creative common Attribution 4.0 International and is published here by the Indian Ocean e-Ink under license from the author(s).
