Concerns have been raised that feral pigs are behind a decline in the freshwater turtle population of the Gulf. In partnership with Tagalaka Traditional Owners we set out to investigate.
About half of the known 25 species of freshwater turtle in Australia are considered threatened and listed as vulnerable, endangered, or critically endangered under the Environment Protection and Biodiversity Conservation Act.
While not federally listed as a threatened species, concerns have been raised about a declining population of northern snake-necked turtles (Chelodina rugosa) at Littleton National Park, located 40 km east of Croydon.
Gulf Savannah NRM and Tagalaka Aboriginal Corporation’s Turtles in Trouble project is investigating these claims, working to establish a baseline population estimate of the northern snake-necked turtle at Littleton, assessing evidence of threats that could be contributing to a decline in turtle numbers, and building the capacity of the Tagalaka people to carry out turtle monitoring and threat-mitigation activities on Country.
Feral pigs are one of the main threats identified for northern snake-necked turtles. In environments lacking permanent water, turtles can aestivate — this means they bury themselves in mud and river sands — during the dryer months when seasonal wetlands and watercourses have dried up, but this makes them particularly vulnerable to predation from pigs, who root and forage for food in dry riverbeds and along the water’s edge.
Pigs also prey on turtle eggs and negatively impact turtle habitat through activities like mud wallowing and destroying the sensitive plant communities at the edges of waterholes.
In 2023, Gulf Savannah NRM’s Biodiversity Officer, Dr. Edward Evans, along with freshwater ecologist Jim Tait, Tagalaka Aboriginal Corporation RNTBC and the Tagalaka Rangers, conducted two surveys at Littleton National Park. These surveys, in June and December, collected population data and observed seasonal characteristics and behaviours.
A range of riverine and floodplain sites at the national park were surveyed using a combination of passive fyke nets and baited turtle traps, which are modified crab pots.
Read the full article in the Gulf Croaker: