Loggerhead sea turtle although loggerhead sea turtles cannot retract their heads or flippers into their shells. Sexual dimorphism of the loggerhead sea turtle is only apparent in adults. Adult males have longer tails and claws than females. The males' plastrons are shorter than the females', presumably to accommodate the males' larger tails. The carapaces of males are wider and less domed than the females', and males typically have wider heads than females. The sex of juveniles and subadults cannot be determined through external anatomy, but can be observed through dissection, laparoscopy (an operation performed on the abdomen), histological examination (cell anatomy), and radioimmunological
Loggerhead shrike shrikes may eat or discard their bodies or else feed them to their remaining young. The oldest recorded age of a loggerhead shrike was 12 years and 6 months. Loggerhead shrike populations have been decreasing in North America since the 1960s. Reasons behind the decline remain unclear, although suggestions include habitat loss, pesticide contamination, climate change and human disturbance. The eastern loggerhead shrike ("L.l. migrans") is critically endangered in Canada, with fewer than 35 known breeding pairs in Canada. The San Clemente Island shrike, "L. l. mearnsi", is critically endangered, with a population as low as 5-10 individuals during 1983-1988.