Leatherback turtles range from 70°15’N to 27°S in the Atlantic, Pacific and Indian oceans. The main nesting beaches are in Mexico, Costa Rica Irian Jaya, French Guiana, Suriname and Gabon. In Canada, turtles have been observed in the waters off Nova Scotia, New Brunswick, Newfoundland and Prince Edward Island.
Virtually nothing is known about hatchling and juvenile habitat requirements, however, since they are never seen in temperate waters, It can be assumed that leatherbacks acquire a cold tolerance as they mature, possibly due to their increased body size.
Adult leatherback turtles are highly migratory and spend most of their lives on the high seas. They are seen regularly along the continental shelf off the Canadian coast, presumably due to the high concentration of prey. Their use of temperate water habitat seems to depend on the abundance of prey.
The largest colony in the Caribbean region is located in Yalimapo near the border with Suriname. As is typical of long-term databases at well-studied nesting beaches, the French Guiana database demonstrates strong fluctuations in the number of nests laid each year, ranging (since 1978) from more than 50,000 nests to fewer than 10,000.
The number of nests laid at Yalimapo has been steadily decreasing since 1992. Although the nature and extent of the decline are difficult to interpret (due to the highly dynamic nature of beaches and the consequent evolution of nesting patterns), the trend is clear. By averaging the data over the years (which reduces the effects of annual fluctuations), we average a number of nests laid per year between 1993 and 1998 was 18,100.
There were less than 100 leatherback turtle nests laid in Suriname in 1967, but the number steadily increased to a peak of 12,401 nests in 1985 and has fluctuated widely since then. A minimum of 4,000 nests were laid in Suriname in 1999, of which about 50% were lost to poaching.
More moderate-scale operations are reported in Guyana, Venezuela, and Colombia. Sea turtles have been used extensively on nesting beaches in Guyana for many generations. The most important nesting area is the North-West District, especially Almond Beach. Pritchard (1986)estimated that 80% of females were killed each year as they attempted to nest.
In 1989 an intensive tagging program began in collaboration with local communities, and rates of mortality have since declined. The number of nests laid at Almond Beachfluctuates among years and ranged from 90 to 247 between 1989-1994; The Acandí region (Gulf of Urabá), specificallyPlayona Beach, is the most important nesting site(for leatherbacks) in Colombia.
During 11 weeks of monitoring 3 km of nesting beach at Playona in 1998, 71 females were tagged and 162 nests were confirmed. In 1999, 180 females were tagged and 193 nests were confirmed). Current threats to the colony are considered serious and include direct harvest, incidental catch by fisheries, pollution, upland deforestation, and coastal development.
Local experts define leather nesting in Panama as being in decline; Polls are needed to confirm the speculation. Between Costa Rica and Escudo de Veraguas (Bocas del Toro Province), some 35-100 gravid females are killed each year and egg poaching is estimated at 85%.
Most leatherbacks are killed near the Changuinola River, where the meat is later found for sale in Changuinola and the banana plantations for US$0.25 per lb. Costa Rica has seen dramatic declines in some areas due largely to egg poaching, which still approaches 100% outside of protected areas.
An estimated 70% of all leatherback nesting in Caribbean Costa Rica occurs within the protected areas of Gandoca-Manzanillo wildlife refuge, Pacuare Nature Reserve, and Tortuguero National Park, where the combined number of breeding females per year is 5,00 to 1,000, making it the third-largest known breeding group in the wider Caribbean region.
The population of the Gandoca Manzanillo Wildlife Refuge is increasing, with the number of nests per year varying from 200 to more than 1,100 between 1990 and 1999. In Honduras, there is a small colony 2575 nests per year at Plapaya Beach which has been protected by MOPAWI and the Garifuna community since 1995.
Breeding is described as rare in Mexico, where possibly fewer than 20 nests are laid each year on the entire Caribbean coast and the Gulf of Mexico. With the exception of Trinidad (and possibly the Dominican Republic), nesting in the insular Caribbean is predictable but does not occur anywhere in large numbers, i.e. more than 1,000 nests (or about 150 females) per year.
There is considerable anecdotal evidence that nesting has dramatically declined throughout the eastern Caribbean. In the British Virgin Islands, for example, six or more females nested per night on beaches on the northeast coast of Tortola in the 1920s. Turtles were harvested primarily for the oil, which was (and is) used medicinally. In 1988, only one nest was recorded in Tortola; in 1989 there were none.
There were 28 crawls (successful and unsuccessful nesting events, combined) on Tortola in 1997, 10 in 1998, and 39 in 1999, suggesting local nesting of 2-6 turtles per year. Egg theft and the killing of egg-bearing females have combined to shrink the once-thriving colonies of St. Kitts and Nevis, St.Lucia, Tobago, and elsewhere on the Caribbean island.
On islands where nesting appears to have been historically rare or occasional (eg., Anguilla, Antigua, Barbados, Jamaica, Netherlands Antilles), it is impossible to estimate current trends. The news is better in some areas where protective measures have been strong.
Nesting at the Sandy Point National Wildlife Refuge, USVI, where leatherbacks have been protected for nearly three decades, is showing a clear upward trend. An average of 26 females nested (with an average of 133 nests laid) each year between 1982-1986 and an average of 70 females brooded with an average of 423 broods each year between 1995 and 1999, almost tripling in two decades ( Similar trends are seen at Culebra National Wildlife Refuge (PlayaResaca and Playa Brava), Puerto Rico, where an average of 19 nested females (with an average of 142 nests laid) each year between 1984 and 1986 (east coast) and Grande Rivière (north coast), were declared protected areas in 1990 and 1997 respectively.
Systematic tagging began at Matura in 1999 and 862 females were tagged, but beach coverage was Incomplete and only more than 1,000 females probably nested almost 10 km from the beach that year. A similar number of females (800-1,000 per year) are believed to nest at Grande Riviere.
The status of the nesting colony in Trinidad is unknown. Community-based beach patrols have reduced the number of females killed each year to near zero (down from an estimated 30-50% per year on the east coast and near 100% on the north coast in the 1960s and 1970s), but high levels of incidental catch offshore have the potential to decimate the colony.
Erzsebet Frey (Eli Frey) is an ecologist and online entrepreneur with a Master of Science in Ecology from the University of Belgrade. Originally from Serbia, she has lived in Sri Lanka since 2017. Eli has worked internationally in countries like Oman, Brazil, Germany, and Sri Lanka. In 2018, she expanded into SEO and blogging, completing courses from UC Davis and Edinburgh. Eli has founded multiple websites focused on biology, ecology, environmental science, sustainable and simple living, and outdoor activities. She enjoys creating nature and simple living videos on YouTube and participates in speleology, diving, and hiking.