Found along tropical coastlines, thick mangrove forests were once considered a nuisance, infested with mosquitoes and blocking the coasts. But now we know that mangroves are crucial to coastal ecosystems. The mangrove tree's unique ability to put down roots at the ocean's edge creates homes for hundreds of other species. Young fish and shrimp find shelter among the trees' tangled roots.

Location: warm areas along the coasts of Africa, Asia, Australia, the Pacific islands, South America, and the Caribbean
Characteristics: thick forests of jagged
mangrove trees, their roots, and deep black mud
Closely linked habitats: seagrass beds and coral reefs
Importance: prevent erosion along coasts, and reclaim areas destroyed by hurricanes

Image credits: main image, courtesy of OAR, National Undersea Research Program.