Alligators dig change

Alligators are one of the Florida Everglades’ most famous predators. They sit at the top of the food chain and influence the world around them by how they hunt and what they eat. But FIU biologist Bradley Strickland believes they also impact the ecosystem from the bottom of the food chain up.

The Ph.D. student is studying how alligators move nutrients in the environment by digging out holes in the wetlands with their snout, feet and tail. Known as alligator holes, they help the reptiles keep cool during hot weather and successfully mate. The holes also store water during the dry season, providing refuge for wildlife that might end up as alligator prey, including birds, fish, insects, snakes and turtles. By examining water and soil chemistry, Strickland is investigating whether burrowing alligators stir up phosphorous and nitrogen found in the soil and distribute these nutrients to other parts of the Everglades through the water, helping to feed organisms at the bottom of the food chain such as algae.

“You are what you eat, so we can sample small fish and aquatic invertebrates and see what the food web structure is like,” Strickland said. “If that structure is different in the alligator ponds than in the surrounding marsh, we can begin to measure what ecosystem-level changes are being made by the alligators.”

Bradley Strickland poses with an American alligator in the Florida Everglades.

Bradley Strickland poses with an American alligator in the Florida Everglades.

Strickland is conducing his research as part of FIU’s Florida Coastal Everglades Long Term Ecological Research (FCE LTER) Program, which is dedicated to understanding how water, climate and people impact the Everglades. His research project is funded by the Everglades Foundation’s FIU ForEverglades Scholarship.

Found only in the southeastern United States, American alligators are sensitive to and indicative of changes in the environment. Strickland hopes his research will allow resource managers to better predict the effects of ongoing restoration efforts in the Everglades.