Discontinuité et accessibilité des aires protégées : du modèle insulaire au modèle réticulaire. Exemples des Galapagos (Équateur) et de la péninsule d’Osa (Costa-Rica)

The insularity pattern was chosen to design protected areas, for many of them aimed at conserving isolated ecosystems and endemic species created by geographic speciation. In this model, spatial discontinuity acts as a barrier protecting natural peculiarities, when accessibility means a threat for organisms which evolved in isolation. But this insularity model does not fit the economic valorization of protected areas, which argues from the necessary development of local communities to open up the regions where they are located. Protected areas are therefore organized according to a network pattern : they are split into zones allowing different kind of uses while ex situ conservation and biological corridors are seen as ways to save species threatened by this opening up or, at the contrary, by their confinement into too small sized reserves. However, this network pattern does not allow an efficient protection for species issued from geographical spéciation because it reduces discontinuity on behalf of accessibility, often for economic purposes.Grenier Christophe. Discontinuité et accessibilité des aires protégées : du modèle insulaire au modèle réticulaire. Exemples des Galapagos (Équateur) et de la péninsule d’Osa (Costa-Rica). In: Les aires protégées insulaires et littorales tropicales. Actes du colloque DYMSET, TRANSCULTURES, SEPANRIT «Aires protégées insulaires et littorales tropicales», Nouméa (Nouvelle-Calédonie), 30 et 31 octobre 2001. Talence : Centre de Recherches sur les Espaces Tropicaux (Université Michel de Montaigne, Bordeaux 3), 2003. pp. 29-42. (Îles et Archipels, 32