Red Mangrove

The red mangrove (Rizophora mangle) is a native coastal plant also known in other regions throughout the world. Red mangroves often form very intricate thickets along the shorelines. These thickets provide shelter to a large array of organisms that depend on them for their survival. Probably the most interesting ecological fact about mangroves is that they act as "water filters" that clean the water in their surroundings.

Mangroves are extremely well adapted for dispersal across water and are found on tropical and subtropical beaches all over the world. This tendency to move from place to place carried by ocean currents explains why the mangrove species that inhabit the coastal zone of the Galapagos are not endemic.

With today's picture I want to illustrate some of the interesting adaptations red mangroves have to their unique life style. The special roots called "prop" or "stilt" roots help mangroves literally "to walk", winning territory. The roots are often called "walking sticks" and this comes from the fact that their characteristic "out of the soil" red roots really look like big-legged sticks.

Another important adaptation is found in the middle layer of this plant's fruit, which is filled with a spongy material that provides them with buoyancy. This feature makes red mangroves an excellent candidate for long distance dispersal across the oceans. In addition, red mangrove seeds can float on the ocean without rotting for more than two years! Mangrove seeds begin to germinate while still attached to the parent plant. Due to this interesting fact they are called "viviparous", a condition seldom found in the plant kingdom. The sprouted young seedlings will eventually drop off the parent plant to begin a new life on their own. They fall upright due to gravity and are buried in the soft, moist sandy soil. If the seeds fall into the ocean, they often take a long journey to a hospitable beach where they may find the right conditions for growth and begin a new mangrove colony.