By: Kyle Grammatica
A recent study by the University of Florida examined how Florida’s crocodiles have responded to changes in the Everglades ecosystem over the last 40 years. American crocodiles, and their relatives, American alligators, are keystone species that reflect the health of the entire ecosystem.
“Crocodiles may look burly and resilient, and we think of them as ancient dinosaurs, but they are vulnerable to changes in the environment, including human-caused changes to their natural ecosystem,” said Venetia Briggs-Gonzalez, the lead author of the study.
Researchers were interested particularly in the effects of ongoing Everglades restoration efforts and rising salinity levels in Florida Bay. To find answers, they conducted long-term capture-recapture assessments on 10,000 south Florida crocodiles from 1978 to 2015, measuring growth, survival rates, and body conditions.
One key finding: crocodiles in south Florida began shifting their traditional nesting locations to avoid areas with high salinity. Northeast Florida Bay was a nesting hotspot, but the crocodiles began moving away as the water’s salinity increased. Increased salinity in the water has also influenced crocodile’s overall health and survival rates.
“High salinity is not good for wildlife, especially those that require freshwater,” said Briggs-Gonzalez. “Now they have to endure salty water and crocodile babies need fresh water to survive. High salinity threatens a crocodile’s growth and body condition too. It is a cascading effect that has an impact on all aspects of their lives.”
Luckily, the researchers say there are signs of improvement in the ecosystem, especially by getting the Everglades water quality right. They also noted that Florida crocodiles are doing better than those in many other parts of the world. The researchers will continue to monitor the population’s health and hope to see progress in the coming years.
Support the conservation of iconic Florida species like crocodiles, by purchasing our Conserve Wildlife license plate online here!
