Biologists studying young Loggerhead
turtles in the Mediterranean Sea were startled to find from their genetic
comparison that roughly half the immature turtles feeding there came from
beaches of Florida, Georgia and South Carolina.
Apparently the immature turtles remain in the pelagic system for about 12 –
15 years. Those that enter the Gulf Stream would encounter the North
Atlantic gyre, a huge circular current that carries them toward Europe. A
branch of the gyre enters the Mediterranean Sea and along with it go these
The navigational ability of the young turtles is essential for their survival during those travels. It can be fatal if they stray beyond the latitudinal extremes of the current.
The current divides as it approaches Portugal. The northern branch continues up past Great Britain and the water temperature falls rapidly. Turtles swept north in that current would soon perish from the cold. Similarly, turtles that drift south of the current risk being swept into the South Atlantic Current and carried far south of their normal range.
Therefore, an ability to recognize the latitudinal extremes of the current and to respond by swimming in an appropriate direction makes all the difference between life and death.
Unfortunately, other hazards now exist. The records show that many of the immature turtles are hooked and perish on the long-lines set out by fishermen. These run out as far as 75 miles and are armed with millions of hooks. The turtles pass these terrible lines all along their route in both the Atlantic Ocean and the Mediterranean Sea.
Therefore, our poor little hatchlings face a triple whammy. As though it weren't tough enough getting by the predators on our beach just to reach the water, now they must run the gauntlet of long-lines in their travels, as well as the nets of the flotilla of trawlers off our beach upon their return to nest.