Loggerhead turtle - Population & Distribution

Global voyager

Current Population and Distribution
Worldwide numbers of marine turtles are almost impossible to calculate because of the wide range of these migratory animals. It is possible to estimate numbers of adult females on nesting beaches, however not all of these sites have been surveyed, and numbers may be confused due to uncertainty about how many times a female nests in a season. A recent estimate of the numbers of nesting female loggerheads is 60,000+.

Studies on mitochondrial DNA of Atlantic and Mediterranean populations has revealed six demographically separate groups, corresponding to nesting beaches in:

(1) Carolina, Georgia, and northeastern Florida, USA,
(2) Southern Florida, USA,
(3) Northwestern Florida, USA (the Gulf of Mexico panhandle),
(4) Quintana Roo, Mexico,
(5) Bahia, Brazil, and
(6) the Peloponnesus, Greece.

Masirah Island, Oman appears to support the largest single nesting population, with a minimum of 30,000 females estimated to nest annually in the 1980s. The second most important region is the southeast USA, where 5,000 to 15,000 females nest annually, mainly in Florida.

Elsewhere, there are major nesting populations in Western Australia and Queensland, and low to moderate numbers nest at sites in the central and eastern Mediterranean, Japan, and many other sites in the warm temperate areas and the subtropics. Nesting is sparse in the Caribbean and most other tropical areas.

Loggerheads are the most common turtle in the Mediterranean, with nesting reported from many coasts, especially in Greece, Turkey, Cyprus and Libya.

In the Indian Ocean, the coast of northern Natal (South Africa) and Masirah Island, Oman are the main nesting sites. Scattered small nesting populations occur throughout Southeast Asia to Australia, but rarely in the central and western Pacific islands.