Evaluating the potential for transboundary management of marine biodiversity in the Western Indian Ocean

Abstract

The economic and socio-political interactions between countries can have major impacts on transboundary conservation decisions and outcomes. Here, we examined for 14 Western Indian Ocean (WIO) continental and island nations the extent of their marine coral reef species, fisheries and marine protected areas (MPAs), in the context of their geopolitical and socio-economic connections. We also examined the role of external countries and organisations in collaboration within the region. We found large variation between the different countries in their protected area size, and management, which result from different interests in establishing the MPAs, ranging from fisheries management, biodiversity conservation to asserting sovereignty claims. Seventy-four per cent of the 154 MPAs in the region belong to island nations; however, the largest MPAs in the WIO were established by European powers, and include Mayotte and Glorioso Islands (France) and Chagos (UK). While the majority of MPAs are managed by individual countries, between-country collaboration within and outside the region is key if the aim is to achieve effective conservation of ecosystems and species across the island and mainland nations in the region. This may be advanced by creating transboundary MPAs and by regional conservation investment by external powers that benefit from the region's resources.

Conservation needs exposed by variability in common‐pool governance principles

“…Consequently, these reef areas are priorities for protections intended to resolve local and international fisheries conflicts (Levin et al. ; McClanahan & Abunge ). The most sampling took place in southern Kenya, Northern Tanzania, and Pemba (Zanzibar) Island at the boundaries of these 3 nations.…”

“…These marine areas have been identified as having coral reefs with high diversity and potential for climate refugia (Ateweberhan & McClanahan 2016). Consequently, these reef areas are priorities for protections intended to resolve local and international fisheries conflicts (Levin et al 2018;McClanahan & Abunge 2018). The most sampling took place in southern Kenya, Northern Tanzania, and Pemba (Zanzibar) Island at the boundaries of these 3 nations.…”

Incorporating feasibility and collaboration into large-scale planning for regional recovery of coral reef fisheries

“…E was included because new management activities are likely to be more feasible in areas where current management practices are successful. C represents the potential for collaboration between countries, and was calculated by normalizing country-level collaboration scores from Levin et al (2018) between 0 and 100 using a fuzzy logic linearly decreasing membership function and spatially assign ing these country scores to planning units. These collaboration scores were derived using linkages between nations based on biodiversity (number of shared species), trade (import/export value be tween countries), governance (number of shared environmental agreements), and spatial location (geographic relationship) (Levin et al 2018).…”

“…C represents the potential for collaboration between countries, and was calculated by normalizing country-level collaboration scores from Levin et al (2018) between 0 and 100 using a fuzzy logic linearly decreasing membership function and spatially assign ing these country scores to planning units. These collaboration scores were derived using linkages between nations based on biodiversity (number of shared species), trade (import/export value be tween countries), governance (number of shared environmental agreements), and spatial location (geographic relationship) (Levin et al 2018). We used Thiessen polygons (Thiessen 1911) to determine the nearest ex clusive economic zone (EEZ) boundary for each planning unit, and assigned planning units the collaboration score for the 2 countries that share boundaries ( Fig.…”

“…For example, a planning unit where the closest EEZ boundary is between Kenya and Tanzania would receive the C value for Kenya−Tanzania collaboration. Areas of high collaborative potential may be more feasible for management when considering cross-boundary collaboration, especially for reefs located between 2 countries or territories (Levin et al 2018).…”