Rockford Rico was a criminal who was active in New Orleans during the 1940s. At the time of his arrest, he had earned the moniker of "The Strangler". In 1941, he had broken free from the chain gang he was forced to work on and fled into tho swamps outside New Orleans. There, he developed the identity of the Turtle-Man and provided refuge for other escaped cons in the swamps.
By the beginning of 1943, Rico had amassed an army large enough to strike back against those who arrested him and his minions. At that time, a troop from Camp Lehigh, Virginia were on marching duty through the swamp -- among their numbers included Private Steve Rogers and James Barnes, who were secretly Captain America and Bucky. During their patrol, they passed a chain gang which included the criminal "Killer" Bane, who managed to break free form his bonds and escape the authorities. Captain America and Bucky followed him into the swamp. However, the two heroes and the authorities ran into the Turtle-Man who had taken Bane into his protection and attacked them with an army of snapping turtles and eventually the Turtle-Man disappeared into the swamp after soundly defeating Cap, Bucky, and the prison guards seeking to recapture Bane.
Following this victory, the Turtle-Man then organized his army of criminals in attacking the Mardi Gras parade to steal some valuable jewels from one of the floats. This led to another clash with Captain America and Bucky, but the Turtle-Man and his men fled with the stolen loot, taking it back into the swamp with them. Captain America and Bucky followed after him and were led into a quicksand trap but managed to break free. Finding the Turtle-Man and his men, the two heroes beat the gang into submission. Fighting one-on-one, Captain America knocked out Turtle-Man, shattering his protective shell in the process. When the authorities arrived, they unmasked him revealing his true identity and was taken back into custody. His subsequent activities are unknown.
Turtle-Man wore a suit that mimicked the body of a snapping turtle. It had a sharp beak that he could use to rend objects. A harsh shell that he could tuck his limbs and head into. The shell was bullet proof and impervious to powerful blows from Captain America but was not indestructible.
Turtle-Man trained a group of snapping turtles to attack on command.