Unfortunately we have had a significant impact on turtles over time. Here in Australia turtles were hunted mercilessly for their shells and meat by colonial sailors who used the meat as a long-lasting source of food when making long journeys between islands. Turtle soup was also once a booming export industry.
The shell of the hawksbill turtle is prised for making ornaments and jewellery and though hawksbill products were banned internationally in the 1990s, the illegal trade continues and new demand has recently re-emerged.
Even though turtles are now protected they still face considerable threats from human actions.
Some of the major threats include:
Light pollution: Artificial lighting discourages the majority of nesting females from coming onshore. Turtle hatchlings use light and reflections from the night sky to find their way to the water following the light horizon. Artificial lighting on nesting beaches cause confusion and disorientation to sea turtle hatchlings and results in them heading in the wrong direction. Unfortunately this is likely to result in hatchling death due to dehydration and increased exposure to predators.
Commercial Fishing: Turtles often congregate in the same areas as commercially valuable fish and can be prone to becoming bycatch—this refers to the inadvertent capture of non-target animals in fishing gear. The leading cause of sea turtle deaths in the last 50 years has been commercial fisheries bycatch—mainly in shrimp trawls, gill nets, and longline fishing gear.
Climate Change: Increased sand temperatures on nesting beaches due to climate change can result in nest mortality. Rising sea levels threaten to flood traditional nesting sites, decreasing suitable nesting site availability.
Vehicles such as Beach cleaning tractors and other 4WD drivers crush nests and compact the sand, making it very difficult for the hatchlings to emerge. Deep tyre tracks in the sand can create a trap for the hatchlings, making them easy targets for predators and exposing them to high temperatures and dehydration. It is important to avoid driving high in the dunes during nesting season. Turtles also face threats from water vehicles such as boats, jet-ski’s and other watercraft.
Marine Debris: Thousands of tons of rubbish is dumped into the oceans every day around the world putting all marine life under significant threat. Turtles often mistake plastic for jellyfish and consume it, resulting in sickness, floating and death. Microplastics also cause sickness due to accidental consumption, it is estimated that there are 5.25 trillion particles of plastic floating in the ocean. Injuries from entanglement with abandoned fishing lines and lures and other forms of marine debris is another threat.
Predation: Turtle nests and hatchlings are naturally predated upon by lace monitors, crabs and birds, but domestic pets such as cats and dogs, and feral animals such as foxes and pigs also pose a significant threats to eggs and hatchlings.