Time-activity budgets and displacement rates in Florida manatees (Trichechus manatus) in the absence and presence of humans

The effects of human presence on displacement behavior and time-activity budgets of free-ranging manatees (Trichechus manatus) are poorly known. The congregation of manatees and human tourists in the warm waters of Crystal River, Florida, during the winter months offered a unique opportunity to study these effects. Focal animal sampling was used to gather behavioral data on manatees during randomly selected daylight sampling periods. Frequencies of displacement were correlated with numbers of humans to determine if incidences of displacement were increased. Displacement increased with human presence. Maintenance and sexual behaviors decreased as human presence increased.