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U.S. State Law
Some states have other laws and regulations regarding possession of red-eared slider because they can be an invasive species where they are not native and have been introduced through the pet trade. As of July 1, 2007, it is illegal in Florida to sell any wild type red-eared slider, as they interbreed with the local yellow-bellied slider population – Trachemys scripta scripta is another subspecies of the same species, and intergrades typically combine the markings of the two subspecies. However, unusual color varieties such as albino and pastel red-eared Slider, which are derived from captive breeding, are still allowed for sale.[11]
Australia
The red-eared slider turtle is banned in Australia because of the threat the species poses to wildlife. Anyone that keeps or breeds red-eared slider turtles could face fines of more than $100,000 or five years' jail.
Que viene a decir lo que ya te han comentado, es una especie invasiva y no se debe soltar en ningún sitio de donde no sea autóctona.