How to improve the management of transboundary commons? Scenarios from an agent‑based model simulating the effects of boundaries and communication in the case of Amazon mangroves. XIX Biennal IASC Conference. Kenya – Nairobi

How to improve the management of transboundary commons? scenarios from an agent-based model simulating the effects of boundaries and communication in the case of crab fishery in the Amazon mangroves Daniesse Kasanoski1, Emilie Coudel2, Christophe Le Page2, and Frédéric Mertens1 1Centro de Desenvolvimento Sustentável. Universidade de Brasília (CDS – UnB), Brazil, 2Unité Mixte de Recherche Savoirs, Environnement et Sociétés (UMR SENS – CIRAD), France To increase the chances of successful management of a common resource, communication among resource users is fundamental to align management strategies, as well as clear spatial boundaries around resource systems to avoid open access. Nonetheless, specific challenges arise in the case of transboundary commons which cannot be contained in areas delimited by human-defined boundaries. Crab fishery practiced in the mangrove forests of the Amazon coastal zone in Brazil deals with a typical transboundary resource; Marine Extractive Reserves have been created to organize the use of ecological resources among its beneficiaries. By analyzing this socioecological system, we observed that although setting boundaries is challenging, communication among fishers of the same community helps them decide where to fish. Based on our field results and on literature on the commons related to communication and boundaries, we built an agent-based model called SpaceCoord to simulate different forms of communication between users of a transboundary common resource, and different ways of delimiting resource systems, in order to test their effects on the resource. The results of the simulations show that the level of the resource increased in the scenario without boundaries and without communication, and decreased when the resource system was divided equally among resource users and when they communicated about the address of the fishing grounds they visited, revealing that communication and boundaries can increase the efficiency of resource user to catch more resources in the least amount of time. So, we underline the importance of encouraging communication about the resource conservation.