The Everglades ecosystem depends on the natural seasonal water patterns of South Florida which rely on rain patterns. Historically, the Everglades’ dry season occurs in the winter months whereas the rainy season takes place in the summer. However, the rain does not always fall in the same, predictable way each and every year. The amount of rain that falls influences water levels in the wetlands of the Everglades. The wetlands act like a sponge, absorbing heavy rains to help prevent flooding, and slowly releasing water during dry times to combat drought.
Wading birds can catch more prey more easily when water is shallow. But as the water recedes in the dry season, prey populations can become depleted. As water levels rise in the wet season, prey can be harder to catch, but the deeper water gives prey populations a chance to rebound.
The quality or cleanliness of the water is also important. Water with chemicals enters the Everglades from canals from our cities and from farm fields that produce our food crops. These chemicals, called nutrients, affect how fast or slow some of the plants in the refuge will grow. Too many nutrients can cause non-native plants to grow and crowd out the native ones. Even if a plant is “native” or belongs in the system, excessive amounts of these nutrients can make certain plants grow much too fast which would consequently disrupt the balance of the ecosystem.
Tiny organisms called periphyton are the lowest level of the food chain here in the refuge. Periphyton is a spongy looking mat of algae and bacteria. Fish and invertebrates, like crayfish and apple snails, eat the periphyton. They, in turn, become food for all the reptiles, amphibians, birds and mammals that live here. The kind of periphyton found in the sloughs and open water of our refuge is not found anywhere else in the entire Everglades ecosystem.The quantity and quality of the water in our refuge affect these periphyton and all the animals that depend on them.