Anchoring the forest to the sea, the dendritic roots of the mangroves in South Florida create a world of their own. Here, many organisms find safety from the vast sea just outside. This thriving and complex ecosystem utilizes the shallower water and seeks protection in the cage-like branches above and below the water’s surface. The mangroves are remarkable worlds providing so much to all that is around them, and their vital role in their environment cannot be overemphasized. As a much needed life source, they absorb and store carbon from the air, provide a barrier between marine weather and the land, and turn debris and decay into a nutritious detrital base of the organic food chain. Mangroves are the only ones of their kind that can thrive in these conditions of tremendous heat, suffocating mud, and the saltiest of waters. They have the ability to exclude salt from their intake, and if any salt does make it into their system, it is released through a sacrificial leaf. Mangroves reproduce through a process of “living birth”. When a mangrove reaches maturity, a miniscule flower blooms, a seed pod begins to form, the pod is germinated, and then released as a fully packaged, ready-to-go mangrove seed pod into the water. The tide, wind, and weather carry this pod along until it becomes so waterlogged that it becomes planted into the sediment As more of these pods take residence near each other, islands are formed, islands of these “botanical amphibians”.
We paddle along with dense mangroves on one side and elaborately colored homes on the other. Coming up on a small entrance into the forest, marked by an orange ribbon, we get down on our knees and head in. We store our paddles on our boards and take to the trees as we pull ourselves deeper into the tangled world. The pale branches fountain to green waxy leaves creating a tunnel, and our attention is directed down, beneath the calm water and through the roots.
Cassiopeia, the upside-down jellyfish, rest all along the sand and manatee grass of the lagoons. In order to feed, they must chase the sunlight, feeding on the symbiotic algae that gets trapped in their arms. Resting on the sediment with their arms to the sun, they add a lacey fringe to the quilted bottom. Cnidarians are well represented here in the mangroves as many anemones station themselves among the prop root habitats. The roots also provide support for filter-feeders such as sponges, tunicates, barnacles, and molluscs. The bright cautionary orange of the Fire sponge dresses the roots up in a vibrant pop of color, as does the more innocent colored purple sponge. Outside of the mangroves, one may find the oddness of the Loggerhead sponge and the delicacy of the vase sponge decorating the floor. The starfish adds a friendly shape to this foreign world, and its fellow Echinoderms add yet more variety to this ecosystem, and yes, that includes the sea cucumber casually minding its own business. A Queen Conch walks along the bottom with its muscular foot as it feeds on algae, quietly building its shell along the way. Master architects, they build their shell from the inside out, creating what to us is artwork but to them is merely protection. A couple feet away, a classmate to the conch goes about its daily routine of feeding. A sea hare, unlike the conch, keeps its shell internal and is armed with a brightly colored and perfume scented ink designed to mask its predators for a “not-so-speedy” get-a-away. Many small fishes can be found in the mangroves. Some will grow bigger and work their way out to sea, and some will stay here living among the roots and salt ponds. Nurse sharks, young sea turtles, and traveling manatee may also be found working their way through the channels coming and going with the tide and the changing temperature. We hear a wrestling in the trees and our attention is brought out of the water and we are asked to look up at the branches surrounding us overhead. Tree crabs scatter, hiding just out of sight on the other side of the aerial roots. There is bright sunlight at the end of one channel, and we emerge out of the mangroves and back into deeper water. We stand back up on our boards and begin paddling back towards the marina. A snowy egret carefully watches us from a small island of mangroves as we paddle past.
The mangroves bridge the land to the sea, having a foot in both worlds, and they are among the most productive and biologically diverse ecosystems on Earth. Here, we find passion in the immense amounts of wonder and beauty, appreciation of its life, and a reminder of why we go outside.