A new study by the University of South Australia has found deposits of heavy metals, including silver, in underwater sediment near the South Australian regional town of Port Pirie, has contaminated waters, putting local recreational fishers at risk.
The University of SA study found levels of lead, zinc, cadmium, copper, arsenic and silver in the top layer of sediment surrounding the town exceeded national environmental standards, in some cases by a factor of 50.
The study showed heavy metal contamination continued to be a huge problem for the regional city.
It noted lead and cadmium pollution was particularly worrying given the metals were: “amongst the most toxic of metal contaminants and are known to induce neurological disorders and multiple organ damage even at low levels of exposure”.
Though the pollution means the commercial fishing of mussels and some fish is banned, the study notes: “little awareness exists in the local community and [mussels] remain a target species for local recreational fishers”.
It also highlighted a negative impact on marine species’ diversity and habitat.
“Metal contamination decreases species diversity, changes community structure, results in abundance and biomass decline and degrades habitats,” the study said.
“Consequential effects can include reductions in both marine resource yields and ecosystem services.”
In response to the University of SA report, in partnership with Flinders Ports Holdings, Nyrstar and the Environment Protection Authority (EPA), a 12 month fishing ban has now come into effect, until further investigations are completed.
A temporary closure is in place as a precautionary health and safety measure, and until further notice, any seafood caught within the Port Pirie closure area should not be consumed.
Shore, jetty and boat-based fishing activity is restricted in the closure area as follows:
The fishing ban will stand until September 15th 2021 in the waters adjacent to the Port Pirie township.
Zone 1 – waters south and west of Weeroona Island Boat Ramp and including First Creek, Second Creek and Port Pirie River.
- all species, including all molluscs, crustaceans and fish, must not be taken from this area.
Zone 2 – waters in the Port Germein area, extending north and west from Weerona Island Boat Ramp.
- bivalve molluscs eg. oysters, mussels, scallops and razorfish, must not be taken from this area.