bark removed of Adansonia grandidieri in Bekonazy site (©Andriafidison 2010)

Bark harvesting: a potential threat for the Grandidier’s baobab Adansonia grandidieri in western Madagascar

Daudet Andriafidison, Cynthia Onjanantenaina Raveloson, Willy Sylvio Mananjara, Julie Hanta Razafimanahaka

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.


Keywords


Madagascar; baobab de Grandidier; écorce; Menabe; dry tropical forest; Natural resources;

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