Stretching along miles of Biscayne National Park's western edge is a mysterious place that can remind one of the jungles seen in old movies. From the water, you see an unbroken line of trees with their beautiful, dark green leaves reaching almost to the water. As you get closer, you see that between the water and the leaves is a seemingly impenetrable tangle of prop roots, arching from the tree's trunk to the water. You have reached the mangrove forest – one of the longest continuous stretches of mangroves left on the Florida's East coast.
The word mangrove is used to describe several trees, not closely related to one another, that flourish in salty environments. Some have the ability to block absorption of salt at their roots while others secrete excess salt through their leaves, allowing them to thrive where other trees would die.
These mangroves, with their impenetrable root system, help to keep Biscayne's waters clean and clear by slowing the water that flows into the bay from the land, allowing the sediment carried by the runoff to settle out. These roots also provide shelter and protection for a host of marine organisms, especially the very young and small, while the trees branches above provide breeding and nesting areas for many birds, including the brown pelican.
Leaves fall from the mangrove's branches all year round. These leaves break down to become food for many marine organisms which, in turn, become food for larger organisms including commercially important species of fish, pink shrimp, and the Florida spiny lobster. Without healthy mangrove forests, Florida's vital recreational and commercial fisheries would drastically decline.
Three types of mangroves live in the park, not only along the mainland shoreline, but fringing the park's islands as well. In the textbook situation, starting from the water and working inland, you will find red, black, then white mangroves.
The red mangrove's seeds, known as propagules and resembling large beans or green cigars, germinate on the tree. When they drop from the tree they can float in the water for up to a year before becoming lodged along the shore where they start growing into a new trees.
The Black Mangrove