Document ID: chunk:federal_register_of_legislation:F2017L00641:body:0:p29
Version: federal_register_of_legislation:F2017L00641
Segment Type: other
Provision Reference: 
Character Range: 90281–93339

in turn can result in decreased turtle health, starvation, increased stranding and decreased breeding condition[16]. These pulse events may also deliver sudden high contaminant loads to the system[141]. While the event itself may be of short duration, the loss of the seagrass meadows may continue to impact on turtle health for several years[191].

Chronic chemical and terrestrial discharge
Anthropogenic contaminants can make their way into the marine environment from a wide range of agricultural, industrial and domestic sources, and can have direct impacts on marine turtles and their habitats. While not always fatal, long-term exposure can compromise health and increase vulnerability to other stressors[60]. Some diseases and pathogens are exacerbated by poor water quality[2].
Runoff of nutrients and sediment from land-based agriculture, urban development and coastal aquaculture can impact water quality, causing changes in light and salinity over coral reefs and seagrass meadows, disease outbreaks, and exposure to biotoxins associated with algal blooms[4, 42]. One of the major contributors to ongoing poor water quality in the Great Barrier Reef has been the sediment and chemical runoff from agricultural land, and while there have been many improvements to the management of agricultural land, the sediment loads entering the system are still double to those occurring before European settlement[73].
Heavy metals and persistent organic pollutants (POPs) have been identified in marine turtles in Australian waters[71, 99, 100, 111, 112]. POPs have been shown to maternally transfer to offspring and have been linked with reduced hatchling condition[226] and decreased immune response in loggerhead turtles[123, 124]. However, the long-term effects of turtle exposure to chemical pollutants are not well understood. Preliminary results from the Rivers to Reef to Turtles Project on the Queensland coast suggest that water quality may have sub-lethal impacts on marine turtle health. This project is ongoing and expected to inform management into the future[261].
Legislation is in place to manage the risks of chemical and terrestrial discharge to the marine environment. There are also mechanisms in place, such as the Framework for Marine and Estuarine Water Quality Protection (DEWHA 2002) that has been developed within the National Water Quality Management Strategy to protect the nation's marine environment from the adverse effects of land-based activities.

4D International take
Given their highly migratory nature, marine turtles that are part of an Australian stock may be subject to take when they migrate outside Australian waters. There are also anecdotal reports of foreign nationals coming into Australian waters to illegally take turtles[79, 136]. Take of turtles can assume various forms, from collecting animals and eggs on nesting beaches, to taking animals at sea and includes illegal, unreported and unregulated (IUU) fishing[113].
As the actions required to address international take differ based on the jurisdiction