The fact that Rainer has managed to demonstrate that these marine reptilians play a pivotal role in maintaining coral reef biodiversity makes their fragile status of Critically Endangered all the more alarming. Under serious threat of extinction, the removal of these wardens from the reef could have even more dramatic knock-on effects throughout the ecosystem than previously thought: no longer being preyed upon by turtles, sponges could then out compete corals and dominate the reefs, causing reef ecosystems to support a far lower biodiversity.
Hawksbill turtles are in trouble because they have been harvested for thousands of years mainly for the aesthetic qualities of their shells, which are used to make combs, jewellery boxes, spectacle frames and ornaments. However, somewhat misleadingly, such products are usually referred to as ‘tortoise shell’ despite being produced from the scutes, or shell plates, of the turtles, making the true source of the product less apparent to customers. The exploitation of hawksbill turtles stretches back far through history: after invading Egypt Julius Caesar prized tortoise shell so highly he brought it back to Rome amongst his chief spoils; ninth century Arabs traded in tortoises hell throughout the Indian Ocean; and by 1700 Japanese artisans were carving exquisite ornaments from tortoise shell (called bekko) that were traded in markets around the world. Japan subsequently became the primary buyer of hawksbill turtles, with in excess of 1.3 million dead individuals being imported between 1950 and 1992.
It is predominantly the prolific and prolonged trade in tortoise shell that has left hawksbill turtles facing extinction, but they are also caught for food and their eggs are even harvested to be used as an aphrodisiac, despite merely acting as a placebo. This overexploitation led to the prohibition of trade in hawksbills in 1977 (via their listing under Appendix I of CITES), however the regular interception of smuggled bekko shipments shows the industry persists through poaching. But there is growing support for their protection, with countries such as the Seychelles and Tanzania showing their commitment to stifling this illicit trade by burning all their accumulated stocks of tortoise shell.
Seeing as hawksbills are under serious threat and continue to be exploited despite the moratorium on international trade, what can we as individuals do to help combat poaching? Although it may sound trivial, the main way is simply to not buy tortoise shell products – without the demand then supply should soon curtail as the trade can no longer be sustained. Hand-crafted tortoise shell jewellery and ornaments, as well as stuffed hawksbills, are frequently found at tourist markets in tropical countries, as such curios prove popular souvenirs. An increasingly available alternative for those still sorely tempted is ‘faux tortoise shell’, which is a plastic substitute for the real thing. It is also incredibly important to report any poaching incidents, such as someone attempting to sell live turtles, as local authorities should then be able to apprehend them and release the turtles.
It is hoped that Rainer’s ongoing research on hawksbill turtles can be used to improve their conservation status and strengthen resolve against a potential renewal of the tortoise shell trade, for which Japan continues to lobby. His findings provide important information about hawksbill biology and habitat requirements, which is vital for the effective management of their populations and foraging habitats.
Despite their historic overexploitation and the present threat of poaching, with our help hawksbill turtles can still recover and continue to sculpt the reefs, mediating the endless competition between sponges and corals, and supporting the high biodiversity and productivity on which marine ecosystems depend.