Biology and behaviour
The loggerhead and the green turtle are known to nest in Mediterranean beaches. In the Mediterranean Sea it is possible to count ten different countries with nesting beaches (Cyprus, Egypt, Greece, Israel, Italy, Lebanon, Libya, Syria, Turkey and Tunisia), but probably the Eastern Mediterranean Sea (Greece and Turkey) represents the most important area. It is estimated that 2.280-2.787 loggerheads and only 300-400 green turtle females annually nest in the Mediterranean. Some authors have estimated from 3375 to 7085 nets per season. The number of adults should be higher considering that most of the individuals do not breed every year. Moreover additional specimens of C. caretta migrate from Atlantic population to Mediterranean Sae through the Gibraltar strait during the first half of the year.
The adult survival is considered as the main factor affecting population growth rates, fecundity being less significant; this emphasizes the importance of limiting mainly fishing bycatch of adults.
It is possible to define three main ecological phases in the loggerhead turtle’s life: the pelagic phase, when loggerhead turtles feed on pelagic preys, the demersal phase, when they swim close to the bottom to feed benthic species, and finally an intermediate neritic phase when loggerheads shift from pelagic–oceanic to benthic–neritic foraging habitats (Tomas et al. 2001). During this last phase, loggerheads would feed upon both pelagic and benthic prey. Thus, different types of fishing gear can produce different capture and mortality rates and may affect different ecological phases (pelagic or demersal).
