SC.5.L.17.1 Adaptation and Survival in Florida Plants: The Red Mangrove

SC.5.L.17.1 Compare and contrast the adaptations displayed by animals and plants that enable them to survive in different environments such as life cycles variations, animals behaviors, and physical characteristics.

How Do Mangrove Trees Survive in a Saltwater Wetland?

Red mangroves have three specific adaptations that help them survive in the environment where they are found, and one major weakness that prevents them from surviving in other environments. The mangroves main weakness is freezing temperatures: temperatures below 32 °F will kill a mangrove. For this reason, they are limited to surviving in the south part of Florida.

The red mangroves first major adaptation is its ability to filter salt from the water. The root of the red mangrove has a special membrane that filters salt from the ocean water where mangroves are found. No other plant has this adaptation. Scientists have been unable to create a filter that separates salt from water the way the red mangrove does.

Rookery Bay National Estuarine Research Reserve: The prop roots of this group of red mangroves support the tree in this wetland habitat. The prop roots give the red mangrove its nickname, "the walking tree."

The next adaptation that helps red mangroves to survive in its wet environment is the prop root. The prop root does exactly what it says: it props the plant up. The prop roots grow down from branches to the mud below and supports the plants. These roots sometimes look like legs and give the red mangrove its nickname: the walking tree.

The third adaptation that helps mangroves to reproduce in its wet environment are its propagules. The propagules are not seeds. Seeds contain the parts needed once the plant starts growing. The red mangrove’s seeds start to grow while they are still on the plant. This means that red mangroves give live birth: when seed is still on the tree, it is a living, growing plant. When the mangrove propagules fall, they will land in the water surrounding the plant. Mangrove propagules will float on the water and can be moved (dispersed) far from the parent plant. When the propagule lands on sand, mud, or rock, it will root there and grow into a new tree. Mangroves often grow in tidal bays and estuaries and help to build new land by stabilizing the soil.

These three major adaptations of the red mangrove help it to survive and reproduce where few other plants can grow: the ability to filter salt from the water, stabilizing prop roots, and living propagules that are already growing when they fall from the tree.