A Victorian man and two companies have been charged with more than 250 animal cruelty offences over the deaths of dozens of koalas during a land clearing operation.

The man, who owns a property at Cape Bridgewater, in Victoria’s south-west, and the businesses are accused of clearing habitat that disturbed more than 200 koalas.

At least 70 died or were injured and had to be euthanised.

The charges follow a complex investigation by Victoria’s Conservation Regulator, after Forest and Wildlife Officers responded to reports of injured and starving koalas at the Cape Bridgewater property in February last year.

In a statement at the time, conservation group Friends of the Earth Australia called the incident a “koala massacre”. It said it was “alarmed that such wanton destruction and widespread death and injuries continue to plague the south-west Victorian plantation industry”.

On Wednesday, the state government said a crime scene was established, and a triage centre set up to assess the koalas.

“Sadly, 21 koalas were found dead on site and 49 koalas were required to be euthanised,” it said.

“It is alleged that following assessment of the deceased and euthanised animals, 70 koalas were identified as experiencing, or likely to experience, pain or suffering in the form of starvation and/or dehydration, and 25 of those koalas had also sustained fractures.”

More than 120 koalas were released back into the wild. Another 70 were taken into care and, of those, about 60 have been returned to the wild.

The landowner faces 126 charges under the Prevention of Cruelty to Animals Act 1986 and the Wildlife Act 1975, including 18 aggravated cruelty charges for causing fatal injuries. A forest and earthmoving business faces the same 126 charges.

A separate contracting business has also been charged with one cruelty offence under the Prevention of Cruelty to Animals Act 1986 for disturbing the koala population.

The maximum penalty for one charge of aggravated animal cruelty leading to death is $218,088 for a business, and $90,870 or two years’ jail for an individual.

The maximum penalty for one charge of animal cruelty is $109,044 for a business, and $45,435 or 12 months’ jail for an individual.

The maximum penalty for one charge of illegally hunting, taking or destroying protected wildlife is $9087 and/or six months imprisonment. An additional fine of up to $908 per head of wildlife may also apply.

“We understand the community’s concerns about this case and we have ensured a thorough investigation, which led to these charges,” chief conservation regulator Kate Gavens said.

“Our investigation included gathering a large volume of evidence from the crime scene, as well as mobile devices and witness statements. Techniques such as forensic radiography and pathology were undertaken on all deceased animals discovered on the property to assist in determining when and how the animals died.”

The matter is listed for the Portland Magistrates Court on February 22.

To report wildlife crime, contact Crime Stoppers Victoria on 1800 333 000.