Trinational governance to protect ecological connectivity: Support for establishing an international Gulf of Mexico marine protected area network

The Gulf of Mexico is a semi-enclosed, international sea that is bordered by the United States, Mexico, and Cuba. The three nations share transboundary living marine resources that move freely across political borders. Each nation has a vested interest in protecting the sustainability of living marine resources and the state of the large marine ecosystem. Uncommon, hard-bottom, high-biodiversity habitats occur on the continental shelf within United States, Mexican, and Cuban waters. An existing ecological network connects these hard-bottom habitats via migratory patterns and passive transportation of pelagic organisms through oceanic currents. Regional marine policy is needed to protect transboundary connectivity and ensure sustainability of shared living marine resources. An international network of marine protected areas throughout the Gulf of Mexico would conserve high-biodiversity habitats and ecological connectivity, which preserves the ecosystem's natural resiliency to natural and anthropogenic threats.;Legal systems, laws, and governance regimes of the United States, Mexico, Cuba, and the international arena vary. Although the regulatory frameworks differ among the nations, each has marine policy and governance objectives that support ecosystem-based management. Analysis of marine policy was conducted to propose a trinational policy approach to establish and administer the International Gulf of Mexico Marine Protected Area Network under existing law. Domestically, the three nations each have one or more agencies that regulate marine protected areas, and such agencies would likely administer a transboundary marine protected area network. Internationally, several treaties are in place to protect living marine resources in the Gulf of Mexico. The Cartagena Convention was identified as the treaty to best support creation of the International Gulf of Mexico Marine Protected Area Network based on the treaty's scope and ratification by all three Gulf-facing nations. Collaboration and negotiation under the treaty could support an international memorandum of understanding and creation of a trinational commission to establish and oversee the network.;The marine protected area network would connect sites that share features or biota. Coral reef ecosystems are important sites in the Gulf of Mexico. Four well-studied coral reefs—Florida Keys, Flower Garden Banks, Veracruz Reef System, and Alacranes Reef—are cornerstones of connectivity. Selected coral and fish species that occur at the four cornerstone sites were explored as examples of stepping-stone connectivity among several sites on the continental shelf throughout the Gulf. The selected species exemplify biological connectivity and provide justification for regional connectivity in the human dimension also. Marine protected area practitioners from the United States, Mexico, and Cuba gathered at a workshop in July 2012 to create the International Gulf of Mexico Marine Protected Area Network. Trinational collaborators identified design parameters and candidate sites that demonstrate biophysical connectivity and can be linked through standardized governance methods for sustaining human and environmental health and well-being.;Of the candidate sites identified, several are collections of sites that are unprotected or not comprehensively protected. One example is the South Texas Banks; a case study for site selection was performed for the group of sites. Few biological data are available for the South Texas Banks. Multivariate statistical tests were performed on geomorphic variables that collectively acted as an abiotic surrogate for biodiversity patterns for 12 outer-shelf South Texas Banks. The analysis culminated with a ranking tool to guide prioritization of future biological explorations and site selection for designation of marine protected areas. A minimum of five outer-shelf South Texas Banks was proposed for place-based protection and inclusion in the International Gulf of Mexico Marine Protected Area Network. Similar methodology can be applied to other multi-site candidates to refine the spatial design of the network.;Analyses of marine policy, ecological connectivity, and biodiversity hotspots yielded results that serve as a foundation for the International Gulf of Mexico Marine Protected Area Network. The network's objectives are to preserve natural resiliency to adverse anthropogenic and natural disasters and phenomena, to protect ecological connectivity, and to conserve biodiversity through shared resources and management tools. Continued trinational communication and collaboration are critical for successful ecosystem-based management at the regional scale. Proper trilateral administration of the International Gulf of Mexico Marine Protected Area Network could mitigate adverse effects of chronic and episodic stressors and increase protection of the ecosystem's natural resiliency, connectivity, and biodiversity.