November in iSimangaliso Wetland Park heralds the beginning of one of the most special and awe-inspiring miracles of this world heritage site – the nesting of endangered turtles on the 220km golden shoreline.
Annually, between the months of November and March, leatherback and loggerhead turtles haul their massive bodies out of the Indian Ocean and up to the base of the dunes, to lay their eggs. In this most ancient cycle of life, turtles return with almost magical accuracy to the very same beach where they hatched.
Of the seven species of marine turtles worldwide, iSimangaliso’s protected coastline has five species, and its pristine beaches comprise one of the last significant laying sites in Africa for loggerheads and leatherbacks. Turtle monitoring has been undertaken in the park since the 1960s, with turtles being measured and tagged. The turtles of iSimangaliso have received significant conservation attention, producing a noteworthy increase in the loggerhead turtle population.
“With less than 100 laying females coming ashore each year, iSimangaliso’s leatherback turtles, the most southern population in the world, are rarer than black rhino and critically endangered. This means they could go extinct in our lifetime. Having survived aeons and ice ages along with rhinos, and at a time when over 1 000 biological species are going extinct globally every year, their future survival lies with all of us,” said iSimangaliso CEO Andrew Zaloumis.
“As site managers, our challenge is that once they leave our shores and swim across the high seas, they undertake epic journeys, travelling as far as Australia and India. During these journeys, which occur between nesting periods, the leatherbacks spend their time foraging. They feed on pelagic (open ocean) invertebrates such as jellyfish and this makes them extremely vulnerable to threats such as long line fishing methods and pollution. Plastic bags are often mistaken for jellyfish by these feeding animals, ultimately killing the animals that ingest them.”
There is also strong collaboration with Mozambique’s Ponta do Ouro Partial Marine Reserve (PPMR) – proclaimed in 2009 – located at iSimangaliso’s northern border. Africa’s longest trans-frontier marine protected area now offers greater protection and hope for the preservation of these species, with much improved compliance and monitoring efforts across the border.
According to PPMR’s Park Manager, Miguel Goncalves: “Since 1994 a total of 5 811 tracks from loggerheads and 410 from leatherbacks were recorded. An increase in the number of tracks recorded for both species in the last seven years is likely the result of a better coverage of the monitoring season, according to researchers. Since 2007, loggerheads have laid an average of 220 nests, while for leatherbacks 32 nests were recorded on average per season. The number of loggerhead turtles tagged per season has been steadily increasing, with a record 197 turtles tagged in 2013/14, with an average of 63.9 turtles tagged per season.”
As conservation efforts and scientific knowledge are freely shared between the two countries, the future looks more promising for at least two of the planet’s endangered species.
Leatherbacks undertake long journeys and frequently enter colder currents to find food. They are adapted to conserve heat in cold water. They are the only living reptiles that are warm-blooded, generating their own heat. The adult turtles feed only on jellyfish, but the juveniles may also eat other floating organisms. Long spines that project backwards cover the inside of the leatherback’s throat stop slippery food from escaping. They dive to feed and are able to reach depths of over 350 metres due to their flexible shells, and can stay under the water for up to 37 minutes.
A leatherback turtle becomes sexually mature at between three and five years old, when the carapace is approximately 1 400 mm long. Mating between leatherbacks takes place at sea. Leatherback males never leave the water once they enter it, unlike the females, which crawl onto land to nest.
The Hawksbille turtle is a relatively small turtle, often weighing less than 50 kg. The beak is bird-like. In adults the upper section of the shell is translucent amber, beautifully patterned with irregular, radiating streaks of black, yellow and light red-brown. The curio trade has caused the decline of this species. The scutes are made into jewellery and sold on the black market. In countries like Singapore and the Philippines, it is estimated that up to 100 000 hatchlings are killed for the curio trade annually, highlighting the vital role that protected areas like iSimangaliso play in the conservation of such species.