Loggerhead sea turtle both magnetic and visual cues. When both aids are available, they are used in conjunction; if one aid is not available, the other suffices. The turtles swim at about during migration. Like all marine turtles, the loggerhead prepares for reproduction in its foraging area. This takes place several years before the loggerhead migrates to a mating area. Female loggerheads first reproduce at ages 28–33 in Southeastern United States and Australia, and at ages 17–30 in South Africa. Age at first reproduction in the Mediterranean, Oman, Japan, and Brazil are unknown. Nesting loggerheads have a straight carapace length of . Because
Loggerhead shrike sex an adult loggerhead shrike in the field, as they are sexually monochromatic. However, several studies have reported sexual dimorphism in plumage and size traits. Juveniles possess a paler gray plumage that is subtly vermiculated. The loggerhead shrike can be distinguished from the northern shrike by its smaller size, darker grey plumage and larger black face mask that covers the eye completely. It also has a shorter bill with less prominent hook. Their calls are similar. Their vocal range is broad and varied, and has been described as harsh and jarring. The shrike’s notes include squeaky whistles, shrill trills, guttural