Nutrient transport connects saltwater, freshwater and estuarine ecosystems
By Summit Voice
Alligators get around, scientists have discovered while studying the Shark River estuary in Florida’s Everglades. And as they move between fresh water and saltwater, they may be playing an important role in transporting nutrients between the two ecosystems.
“Nutrient translocation by highly mobile predators like alligators, may be important to the entire coastal Everglades ecosystem,” said scientist Adam Rosenblatt of Florida International University.
Everglades National Park, the largest subtropical wilderness in the United States, has been designated a World Heritage Site, International Biosphere Reserve, and Wetland of International Importance. The Shark River estuary is part of the National Science Foundation’s Florida Coastal Everglades Long-term Ecological Research site, one of 26 sites around the world.
An estuary is a body of water formed where freshwater from rivers and streams flows into the ocean, mixing with the seawater.
Rosenblatt and Michael Heithaus, also of FIU, conducted a study of alligator movements between freshwater and saltwater habitats in South Florida. They published their results in a recent issue of the Journal of Animal Ecology.
The commuter alligators connect very different habitats, creating links between marine, estuarine and freshwater food webs.
Estuaries are critical habitats for many species with recreational, commercial and ecological importance, Rosenblatt and Heithaus wrote in their paper. “They serve as ‘nurseries’ for many fish and invertebrates.
“Alligators need frequent access to freshwater because, unlike crocodiles, they don’t have glands that can excrete salt,” says Rosenblatt.
“Mobile large-bodied species like American alligators are buffered against short-term stress by their size,” he said. “They have the staying power to remain in different habitats for longer periods of time.”