We described and compared population dynamics of introduced flathead catfish (Pylodictis olivaris) between the Satilla River, Georgia, and the Little Pee Dee River, South Carolina. Both of these Atlantic coastal plain rivers are blackwater, low productivity systems that historically supported popular redbreast sunfish (Lepomis auritus) fisheries. Flathead catfish have been established in the Little Pee Dee River since the late 1970s or early 1980s, whereas the species was introduced into the Satilla River in the mid 1990s. Both populations are managed differently by their respective state fisheries agencies with an intensive annual flathead catfish removal program on the Satilla River beginning in 1996 and a more recent, less intensive removal program on the Little Pee Dee River that began in 2011. Results from this study indicate the Satilla River flathead catfish population was characterized as having high relative abundance, high mortality, fast growth rates, and a truncated size and age structure containing mostly younger fish with a maximum age of 12. The Little Pee Dee River population of flathead catfish was also characterized as having a high relative abundance but with slow growth rates and a more balanced size and age structure, containing fish up to age 26. This study expands our population dynamics knowledge of introduced flathead catfish populations along the Atlantic coastal plain and provides a few examples of how agencies in the southeastern United States have met the challenge of managing an introduced apex predator.