 Complete the following phrase:  Within the Zapata Swamp are numerous areas designated for environmental preservation, such as Zapata Swamp Natural Reserve and Las Salinas wildlife sanctuary, which is part of the larger Ciénaga de Zapata Biosphere Reserve IUCN category VI which in total is over 6,000 km2 and the largest protected area, not only in Cuba, but also the Caribbean. The swamp is not only known for its size but also for being the best preserved wetlands in all of the Antilles, designated as a Wetland of International Importance by the 