Largest tropical wetland

Located principally in southwestern Brazil but with small areas within neighbouring Bolivia and Paraguay too, the Pantanal (which derives from the Spanish and Portuguese word for "swamp", "marsh" or "bog") covers a surface area of around 160,000 square kilometres (61,776 square miles) – greater than the total surface area of England. During the rainy season (December–May), some 70–80% of the Pantanal is flooded, and it contains the greatest diversity of water plants in the world. It is by no means a uniform landscape, as it contains a multitude of marsh, open water, swamp forest, savannah and other habitats supporting about 1,860 species of plants, along with 460 bird, 260 fish, 85 reptile and 35 amphibian species.

The Amazon River basin in South America cannot be considered a single wetland, but it includes vast areas of floodplain forest, savannah, marshes and mangroves that in total encompass around 1.7 million km2 (656,373 sq mi) of wetlands.

The Sudd in Sudan has sometimes been referred to as the world’s largest swamp. However, even in high flood waters its total area only slightly exceeds 30,000 km² (11,585 sq mi), and thus falls far short of the Pantanal’s area.