Turtles nesting

Posted on Thu November 27, 2014 in Wildlife.

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 1960’s, 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 1000 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."

Summery statistics for Loggerhead and Leatherback turtles nesting in iSimangaliso
LOGGERHEADS LEATHERBACKS
Population Size 700 females per season 70 females per season
Population trend Increasing Stable
Size (average shell length)  86cm 160cm
Diet of adult turtles crabs, snails and starfish jellyfish
Age to sexual maturity 36 years 12 years
Breeding frequency (number of years between nesting seasons) 3 years 3 years
Reproductive lifespan (number of years between first and last nesting) 18 years 16 years
Number of eggs per female over a nesting season 390 eggs 700 eggs
Emergence success (percentage eggs that produce viable hatchlings)  80% 70%
Number of hatchlings produced per female per season 300 hatchlings 480 hatchlings
Total hatchlings produced per year 63 000-144 000 36 000-52 000