We went up the estuary of the Parque National Marino las Baulas de Guanacaste (the national park we work at) in a small boat to see what’s there. An estuary is a place where fresh river water meets salt water from the ocean. The resulting partly-salt water is called brackish.
This estuary is lined with mangroves. Mangroves are small trees that can grow with their roots in salt water. They are found all over the world on tropical coastlines. Their roots form big tangles in the shallow water which provides excellent cover for birds, small fish, and all kinds of wildlife.
This estuary has crocodiles, howler monkeys, parrots and all kinds of wadding birds.