Mangroves are salt-tolerant shrubs or trees that grow along tropical shorelines worldwide. They inhabit the intertidal zone, with underwater roots that provide substrate for invertebrates such as corals, sponges and tunicates while at the same time sheltering many species of juvenile fish. Above water, mangrove forests provide habitat for many birds, monkeys, and other animals. There are approximately 70 species of woody plants included in this diverse group, representing move than 20 different botanical families. Mangrove forests represent an important ecosystem, one that is gradually disappearing due to a variety of factors that include coastal development and pollution.