A turtle that is one of the world's most invasive species has been spotted at Oyster Bay.
The invasive species team from Sutherland Shire Bushcare found a male red-eared slider turtle in a creek.
These turtles produce lots of offspring and are more aggressive than native turtles found in Australia, and pose a significant threat to them.
"Sadly some people have these invasive turtles as pets and release them into our waterways when they do not want them anymore," the team posted on its Facebook page. "They can live up to 75 years in captivity.
"Not only is that devastating for our native turtles but it may also have significant public health costs due to the impacts of turtle-associated salmonella on human health."
Red-eared slider turtles are recognised reservoirs for the Salmonella bacterium.
They are classified as a Prohibited Dealing under the Biosecurity Act 2015. It is an offence to keep this species.
The species is listed by the International Union for Conservation of Nature as one of the globe's worst invasive alien species.
They are mostly now found in freshwater ecosystems in many developed countries with high densities in urban wetlands.
It is considered an environmental pest outside its natural range because the species competes with native turtles for food, nesting areas and basking sites.
Known as trachemys scripta elegans, the turtle originates from the mid-western states of the US and north eastern Mexico.
Non-native populations of wild-living turtles occur worldwide due to the species being extensively traded as a pet and a food item.
They became a popular pet bcause of their small size as a juvenile. But they grow to be quite larger and can bite. Red-eared slider turtles have been smuggled into, illegally kept released in Australia.
An adult has a distinctive, broad red or orange stripe behind each eye. Narrow yellow stripes mark the head and legs. Some have a dark pigment that covers their coloured markings so that they appear nearly black in colour. Males are usually smaller, and have very long front claws.
They eat fish, frog eggs, tadpoles, aquatic snakes, and a wide variety of aquatic plants and algae.
They are highly adaptable and can tolerate anything from brackish waters, to man made canals, and park ponds.
Red-eared slider turtle may wander far from water and are able to survive cold winters by hibernating. Once available habitat is found the species can rapidly colonise a new area.
In the wild red-eared slider turtles can live for about 30 years.
An officer from Sutherland Shire Council's bushland management team says this is the first known red-eared slider turtle in the shire outside of the Royal National Park.
"The turtle incursion was immediately reported to the Department of Primary Industries (DPI) and the turtle was then handed over to Canberra University where it will assist in important research to improve eDNA detection capabilities of red eared slider turtles," the officer said.
"Red-eared slider turtles present a significant biosecurity risk to the environment.
"Early detection and action is important when dealing with invasive species, and council is taking a proactive approach, with our invasive species team conducting extensive surveys of waterways and wetlands and public education campaigns."
Jack Rojahn from the university says the turtles are troublesome across the world.
"They're incredibly damaging in terms of being invasive," he said. "We're developing a genetic test that will aim to identify the turtle's DNA from water samples, to get some insight into them."
If you have seen a red-eared slider turtle or know someone that keeps them report it to Sutherland Shire Council: 9710 0333 or the Department of Primary Industries.