Alarming levels of pesticides have been found in food sources of the endangered Carnaby’s black cockatoo, including levels well above regulation found at seed spills near grain silos.
Murdoch University PhD candidate Zoe Kissane placed GPS tags on wild black cockatoos in Western Australia’s Wheatbelt and collected seed samples from where they foraged.
The samples, taken from agricultural areas, were then screened for chemical residue.
Zoe Kissane says the level of pesticides present is “alarming”. (Supplied: Healther Beswick)
‘Chemical cocktail’
The three-year study found the Carnaby’s were exposed to 26 different pesticides when eating seeds found near grain silos.
Ten different neurotoxins were found.
Ms Kissane said about 80 per cent of seed samples contained at least one chemical, while at least half had three or more chemicals.
“It really highlighted that there’s a bit of a chemical cocktail that these birds are being exposed to,” she said.
Zoe Kissane’s research aims to investigate the link between pesticides and a paralysis syndrome. (Supplied: Murdoch University)
The study found some pesticide concentrations were “well above” the maximum levels set by regulators, in some cases hundreds of times above what was accepted in food or animal feed.
“These hazards are out there and it’s not just wildlife, but also humans that are potentially at risk,”
Ms Kissane said.
“That was quite alarming.”
Paralysis questions
Since 2012, WA’s black cockatoos have been affected by Carnaby’s hindlimb paralysis syndrome, with birds presenting neurological symptoms like delayed reactions, weakness and paralysis.
Ms Kissane said researchers had suspected pesticides contributed to the disease.
The study spanned five areas in WA’s Wheatbelt region. (Supplied: Murdoch University)
She said finding neurotoxins in foraging areas was a key step forward in determining if there was a link.
“These results point to specific pesticides that may be contributing to [the syndrome], providing us with new insight,” she said.
Ms Kissane said using trackers also allowed her to analyse how often the birds returned to the same grain spill.
“That was quite alarming because birds would continue to go back to sites that had chemical pesticide residues at them,” she said.
“There’s that increased risk then of continual chronic exposure to these substances.”
Zoe Kissane (right) and her research supervisor tagged black cockatoos as part of the work. (Supplied: Dannon Wu)
Regulations under spotlight
Ms Kissane said she hoped the findings would prompt Australia to assess how pesticides were regulated and used.
She said while they “serve a purpose” in agriculture, decades of research showed some had a significant impact on the natural environment.
“Many pesticides still in use in Australia are already restricted or banned in parts of Europe, the UK, and North America due to concerns about human and wildlife health,” she said.
The black cockatoo species is listed as endangered. (Supplied: Rick Wilson)
Ms Kissane said even simple changes could help improve outcomes for the endangered Carnaby’s.
“Limiting access to spilt grain … so removing spills particularly around silo areas,” she said.
Ms Kissane said the “opportunistic” birds also foraged on grain spilt during transport, and stricter regulations around grain trucks could limit exposure.