The marshy areas and bays at the mouths of rivers where saltwater and fresh water mix are called estuaries. Here, nutrients from inland are carried out to sea by currents and tides to nourish reefs, seagrass beds, and the open ocean. Many plants and animals feed, live, or mate in these waters. Conch, crabs, shrimp, and other shellfish thrive here, and several types of jellyfish and other invertebrates call this home. Seabirds, shorebirds, and waterfowl of all types frequent estuaries to feed, nest, and mate. Crocodiles, dolphins, and manatees are regular visitors. Rays, sharks, and tarpon hunt and mate here. During the wet season, the estuaries of Belize pump a tremendous amount of nutrients into the sea.