We examined side preferences in the Florida manatee (Trichechus manatus latirostris) through observations of limb use (right and left flipper) in 123 wild and 16 captive individuals. We also analyzed archival data, the United States Geological Survey Sirenia ProjectManatee Individual Photo-identification Systemdataset, to determine lateralization of evasive action from boats. Wild and captive manatees displayed flipper lateralization at the individual, but not the population level for several behaviors including substrate touches, sculling, and feeding. In contrast, manatees were lateralized at the population level for boat-scar biases,with more manatees showing a left scar bias (45.3%) versus right (34.3%) or dorsal/ambipreferent (20.3%).