Does not form schools but local concentrations may occur at sea or near nesting beaches.
Of every thousand hatchlings, only a few are believed to survive to adulthood; this is characteristic even of stable populations (Dodd 1988). In Georgia, annual survivorship of adult females was 0.81, juveniles 0.70-0.94; see Iverson (1991) for a compilation of survivorship data. Maximum reproductive life span 32 years (Frazer 1983).
Among a wide array of animals that eat loggerhead eggs, raccoons are the most important predators on eggs in the southeastern U.S.; on some beaches they have been responsible for more than 90% of nest mortality (Dodd 1988). Organisms attached to the shell are not known to pose a significant threat.
Cold stunning in estuaries (e.g., Long Island Sound) sometimes can result in significant mortality. See Witherington and Ehrhart (1989) for information on cold stunning in Florida.
Data on heavy metal concentrations in eggs support the hypothesis that the western Atlantic population is composed of demes (Stoneburner et al. 1980).