Alcoa’s plans the ‘number one extinction threat’ to WA’s black cockatoos
By Emma Young
Mining giant Alcoa plans to clear as many as 150,000 potential black cockatoo nesting trees to expand operations through Western Australia’s northern jarrah forest.
The information contained in documents submitted to the state’s environment watchdog represents “undoubtedly the most significant threat to the survival of WA’s black cockatoos”, according to the Greens.
Carnaby’s cockatoos with a nesting hollow.Credit: Philippa Beckerling
The bauxite miner’s submissions to the WA Environmental Protection Authority detail its two expansion proposals south of Perth out for public comment: the Pinjarra refinery and mining operation, and the Huntly and Willowdale mines.
Pinjarra documents show up to 144,500 potential nesting trees could be impacted by the 7500-hectare proposed clearing, representing about 32 per cent of the mapped black cockatoo habitat within the mine development area.
“The proposal is expected to clear habitat critical to the survival of the three black cockatoos species, the woylie, chuditch and quokka,” the documents say.
A potential nesting tree must be a suitable diameter to develop a nest hollow – greater than half a metre at breast height, a girth that takes a jarrah tree 100 years to grow to.
Alcoa’s second proposal before the EPA is to clear a further 4000 hectares for Huntly and Willowdale.
A survey of representing only 12.5 per cent of the clearing area contained more than 10,000 potential nesting trees.
“Given that suitable nest hollows likely take up to 200 years to develop, these trees provide a resource for black cockatoos that is critical for their long-term survival and unable to be replaced in the short-term,” the Huntly referral documents say, citing the federal Department of Agriculture, Water and Environment.
“The retention of these trees is important to secure the supply of hollows in future.”
A forest red-tailed black cockatoo in the Holyoake zone. Credit: Philippa Beckerling
Alcoa further estimated its Pinjarra proposal as having “potential to impact” around 650 trees already suitable for nesting and 300 known to be in use for nesting if no mitigation measures were put in place.
It also impacts habitat for numerous other conservation-significant species including the numbat, western ringtail possum and Carter’s freshwater mussel.
An Alcoa spokesperson said the company acknowledged the significance of the northern jarrah forest to black cockatoo populations, and the number of trees indicated in the EPA assessments relied on estimates “with significant potential variation”.
“A ‘potential nesting tree’ is identified based on its trunk size as having the potential to form a nesting hollow in the future,” they said.
“Many will not develop hollows required for nesting at all, while others may be decades away from doing so.”
The spokesperson said detailed pre-mining surveys were taken to identify and protect known nesting trees with buffer zones before any clearing took place.
The company also focused on returning jarrah and marri trees at appropriate density rates in its rehabilitation, the spokesperson said, and also proposed to reintroduce water sources “to improve habitat functionality”.
The revelations in the EPA documents come a week after the state government rejected Bulletin Resources’ appeal to clear 2.3 hectares of critical cockatoo habitat at Cocanarup Timber Reserve for lithium exploration.
“It is not a climate solution to mine for critical minerals if it degrades intact forests or habitat for supporting threatened species,” Environment Minister Matthew Swinbourn stated in his decision.
A Carnaby’s cockatoo nests in a tree hollow. Credit: Philippa Beckerling
“The environmental values of the application area outweigh the benefits gained from exploration for lithium.”
Greens WA forests spokeswoman Jess Beckerling was elated the minister had upheld the departmental decision on Cocanarup and said the same logic should apply to Alcoa.
“The minister made this decision in part because there is no way that clearing of this critical cockatoo habitat can be offset, and this same situation applies to Alcoa’s proposal,” she said.
“This is undoubtedly the most significant threat to the survival of WA’s black cockatoos.
“There is no way to offset the loss of over 150,000 potential nesting trees … it is vital that the minister recognises this and rejects Alcoa’s proposal.”
A spokesperson said the state government remained “committed to transitioning Alcoa to a modern approvals framework under the Environmental Protection Act and has implemented strict controls on the company’s mining operations during this transition. With the independent EPA assessment currently under way, it would be inappropriate for the Minister to comment.”
Public comment on Alcoa’s proposals closes on August 21.
Swinbourn recently rejected an application to match international classifications and up-list the Baudin’s black cockatoo as critically endangered.
The Baudin’s remains listed endangered alongside the Carnaby’s, with the forest red-tailed black cockatoo listed vulnerable, and habitat loss considered their primary threat.
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