This article is more than 7 months old

This article is more than 7 months old

Investigators at the scene of a “koala massacre” at a cleared gum tree plantation in Victoria say the number of animals killed is likely to rise above 40 as they make their way through 10 kilometres of felled timber.

A major incident response has been set up at the site, on private land near Cape Bridgewater, with koalas being treated by vets for starvation and broken bones.

The state’s conservation regulator said it had assessed more than 80 koalas since arriving on the scene on Friday. About 30 koalas had been euthanised.

The Victorian environment minister, Lily D’Ambrosio, said on Monday the event was “devastating” for the koala population in the Portland region and pledged the government would do “everything possible” to bring the perpetrators to account.

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“Every Victorian can rightly feel not only appalled, deeply saddened and heartbroken, but angry. I am absolutely angry.”

Locals reported the incident to the Department of Environment, Land, Water and Planning (DELWP), which arrived on site on Friday.

Portland resident Helen Oakley posted a video from the site. In the video, she said: “Look at the destruction that they have done and there’s koalas lying there dead ... and there are mothers killed with their little babies. Australia should be ashamed of this.”

Portland resident Helen Oakley speaks of the destruction she had found at a former blue gum plantation in south-west Victoria.

Victoria’s chief conservation regulator, Kate Gavens, said more than 80 koalas had been assessed since Friday and at least 30 had been euthanised.

On Monday she said 40 koalas had died, but that number was likely to rise. “There’s about 10 kilometres of felled timber that we have to get through.”

Surviving koalas were being moved to wildlife carers for treatment and rehabilitation, and carers and vets were on site.

“The conservation regulator’s major investigations team is leading the investigation into how this incident happened and who was responsible,” Gavens said. “Animals that were considered to not require immediate removal have been provided with food and water.

“DELWP are working with the relevant parties on the long-term requirements for the remaining koalas – this may include translocation to suitable sites.”

Andy Meddick, a Victorian state Animal Justice Party MP, visited the site on Sunday and told Guardian Australia the trees in the blue gum plantation had been “bulldozed into piles” around the property.

“I saw at least 10 bodies in just one of those piles,” he said. “A couple had literally been crushed to death when these trees have been uprooted. In one instance, a koala had her arm stuck between two branches and she had starved to death. Animals have been killed, injured and left to starve by whoever has done this.”

D’Ambrosio described the incident as “abysmal”, saying: “We will do everything possible to bring the people responsible for this to account and will throw every penalty available to us at them.”

She said the government would consider breaches of both the Wildlife Act and the Prevention of Cruelty to Animals Act.

Under the Wildlife Act, the conservation regulator said, killing, harassing or disturbing wildlife could attract a penalty of up to $8,000 and an additional fine of more than $800 per head of wildlife.

A crime scene had also been established at Cape Bridgewater.

A logging company, South West Fibre, said it had been engaged to harvest timber from the site in October 2019 and handed the area back the following month.

The company said in a statement: “SWF left an appropriate number of ‘habitat trees’ for the existing koala population and provided details of such in a letter to the landowner noting that the koalas were uninjured and in good health.

“It is understood that subsequent to SWF completing its work, the remaining trees have since been cleared. This is particularly concerning to the foresters and staff who worked assiduously to protect the koalas during the harvesting operation.”

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A company spokesperson said it handed the site back to the owner in mid-November with 72 koalas on site, leaving 10 hectares of “remnant vegetation” on site.

According to the Age, the property is run by Keith Troeth on behalf of his father Russell Troeth. Keith Troeth told the newspaper he had cleared the site last week to return it to pasture.

“We made every effort to do it professionally, we made every effort to minimise any fatality,” he said. “There may have been one or two koalas killed and I’ll wear the responsibility, but it’s not the big hoo-ha it’s been made out to be.”

Russell Troeth declined to comment, referring Guardian Australia to a phone number for staff at the Department of Environment, Land, Water and Planning.

The Australian Forest Products Association (AFPA) said it was launching its own investigation and that the industry was “appalled” at what it described as a “callous act of animal cruelty”.

The association’s chief executive, Ross Hampton, said forestry operators “scrupulously and meticulously follow koala preservation procedures overseen by the Department of Environment in Victoria”.

“I’m advised that the operators in this case were so careful that they even took an injured koala, which they found during inspection, to the vet,” he said. “I’m advised harvest of this area ended in November and the land was handed back to the owner before Christmas.

“It is unclear as yet who bulldozed the trees with the koalas apparently still in them, but it is absolutely certain that this was not a plantation or a forestry company. We support all those calling for the full force of the law to be applied to the perpetrator.

“AFPA will be launching its own investigation. Furthermore, we will be ensuring that none of the timber which has been cleared is touched by any AFPA member.”