southern Madagascar and Natal, South Africa, and an extraordinary 

 nesting concentration occurs on Masirah Island, Oman. In 

 the Pacific, the species is all but absent from the central and 

 eastern areas, but significant nesting grounds are found in 

 Japan, and very important ones in Australia. 



Food habits ; The loggerhead is a carnivore, and its 

 exceedingly powerful jaws, equipped with large, ridgeless 

 crushing plates in adults, are well adapted for a diet of hard- 

 shelled organisms such as molluscs and crabs. On the other hand, 

 the smaller immature individuals are apparently water-column 

 feeders, feeding upon scyphomedusans and pteropods, fish (when 

 they can catch them or find them dead) , and, on occasion, plant 

 material. 



The loggerhead and the olive ridley have largely 

 complementary and non-overlapping ranges, and this is not 

 entirely (although it is largely) a reflection of the subtropical 

 preferences of the former and the tropical predilections of the 

 latter. Some degree of food competition seems likely between the 

 two species, at least between olive ridleys and immature 

 loggerheads. The mature loggerhead is able to utilize a variety 

 of hard-shelled food species that no olive ridley could crack. 



Reproductive ecology ; The reproductive habits of the 

 loggerhead are rather unspecialized. It does migrate, but less 

 spectacularly than the green turtle, and sometimes with less 

 accuracy in locating the precise beach area on which it 

 previously nested. Nesting is colonial, although not intensively 

 so, and there is no evidence of coordinated nesting emergences as 

 there are for ridleys. Mainland shores are preferred, and much 

 nesting takes place on beaches partially protected from 

 terrestrial predators by swamps, sounds, or waterways. Some 

 individuals appear to nest only once or twice in a season, but 

 others may nest five or six times. Loggerheads walk with 

 alternating limb movements while on shore, nest exclusively at 

 night, and often show elaborate apparent evaluation of the 

 quality or temperature of the surface sand by means of thrusting 

 actions of the muzzle. The eggs are relatively small (about 4 cm 

 in diameter) , and typically number 100-110 per nest. Undersized 

 or yolkless eggs are rarely if ever found, but a surprisingly 

 high frequency of albino embryos with severe cephalic deformities 

 has been found. These usually die around the time of hatching. 

 Incubation takes 55-60 days, and, as with all sea turtles as far 

 as is known, the sex of the hatchlings is to a large extent 

 controlled by the temperature of incubation. 



Major threats to survival ; The flesh of the loggerhead is 

 less sought-after for human consumption than that of other sea 

 turtle species, and although illegal egg-collection is a problem 

 in some areas (such as Colombia) , the majority of nesting grounds 

 are in relatively prosperous temperate-zone nations, where 



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