| What's happening to our turtles? |
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Australian Significance Although the population of Hawksbills (Eretmochelys imbricata) in Australia is unknown, Australia is highly important to the Hawksbill as it is here where the largest breeding populations exists as well as rookeries. Australia has two main breeding sites in the Northern part of the Great Barrier Reef as well as the Torres Strait in Eastern Australia. Rosemary Island and Varanus Island are nesting sites in Western Australia. Australia also has a genertically diverse population of Hawksbills as there are two different gene pools from the North West Shelf of WA and the Northern Great Barrier Reef including Arnhem Land. Threats - Dude, where's my turtle? There are many threats endangering sea turtles today:
Today nesting females have decreased up to 67% despite high fecundity rates, but also due to illegal trade of turtle meat, as well as habitat destruction and degradation. Indigenous people in Northern Australia as well as Papua New Guinea still practice hunting Hawksbill turtles in all life stages. This plays a detrimental role in depleting their population as they already have a high mortality rate and take a very long time to reproduce. In other countries like Malaysia, Thailand, Philippines, Cuba, Indonesia and the Solomon Islands have all experienced a decline in Hawskbill turtle populations from hunting. Growth and tracking The turtles which are seen today in the oceans are a minority that have survived the tumultuous life as a sea turtle. Only 2% of hatchlings survive and take more than 25 years to reach sexual maturity. The sea turtle is very sensitive to the Earth’s magnetic field and can use it to navigate open oceans and females use this to return to the beach they hatched from decades previously to lay hundreds of their own eggs.Female turtles do not lay eggs annually. They spend a number of years reserving energy for the effort required for reproduction. During this time early egg yolks grow from 3mm to 2cm wide . In summer she will migrate with males to mating areas near nesting beaches where she hatched on many years ago, known as her natal beach. Hawksbills are very slow growers and reach sexual maturity after 31 years. They spend their first few decades in the pelagic waters of the ocean where 99% of offspring produced perish. Research has shown that Hawksbills are highly migratory travelling 2400km between nesting and feeding grounds. Flipper tags that have been recovered show that Hawksbills travel from the Northern Great Barrier Reef to feeding grounds in the Gulf of Carpentaria, south-eastern Indonesia and southern Papua New Guinea. Hawksbill Trade The Hawksbill Turtle is highly prized for its beautiful heart shaped domed carapace, which has made it culturally significant for villagers in Papua New Guinea, and also helped to establish a trade commodity between villagers and early European traders. However, Papua New Guinea's tourism industry is steadily growing and villagers are selling tortoiseshell products to holiday makers. Many of whom are oblivious that their new earrings were made from the magnificant creatures they saw snorkelling in the lagoon. Currently, the only species of marine turtle to be protected in PNG is the Leatherback. Recent research shows that tortoiseshell trade in PNG focuses on the manufacture of jewellery and motifs for the tourism industry. 98.8% of the trade in marine turtles in PNG were of Hawksbill turtles in this study. Compared with countries like Vietnam and the Carribbean, the trade in Hawksbill turtles is very minor. However, turtles which are protected in Australian Waters migrate to waters where they are unprotected and this is a major risk facing the populations of Hawksbill in Australia. Today nesting females have decreased up to 67% despite high fecundity rates, but also due to illegal trade of turtle meat, as well as habitat destruction and degradation. The majority of Australia’s population live on the eastern seaboard, where endangered sea turtles nest, and if their habitats have not been destroyed by development already, our glowing lights at night confuse hatchlings and cause them to crawl towards this artificial sun, and away from where they need to be, the ocean.
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Six of the seven species of sea turtles are found in Australian waters, all of which are endangered or vulnerable. All six species of sea turtles are protected in Australian waters under the National Parks and Wildlife Conservation Act 1975. SACF contributed to a long term monitoring project undertaken by Dr Ian Bell to find out what the main threats to these slow-growing, prehistoric animals are. 
