"Eat them alive." A survival expert believes wanted Canadian teens are dead or close to it, & more in News in 5.

With AAP.

1. “Eat them alive.” A survival expert believes wanted Canadian teens are dead or close to it.

Canadian authorities are scaling back their search in northern Manitoba for the suspected teenage killers of Australian backpacker Lucas Fowler, his US girlfriend and a British Columbia botanist after an extensive manhunt failed to find them.

Police acknowledged that after eight days of no official sightings of Kam McLeod, 18, and Bryer Schmegelsky, 19, the duo could be dead or had left the area.

The Royal Canadian Mounted Police deployed a massive contingent of personnel and were assisted by Royal Canadian Air Force planes equipped with infra-red cameras and imaging radar to search 11,000 square kilometres around the town of Gillam and surrounding wilderness.

More than 500 homes and buildings were canvassed and train tracks, trails and other locations were searched but authorities have failed to make any confirmed sightings.

Leading Canadian survival expert Dave Arama said if the teenagers attempted to hide in the wilderness and did not have the appropriate gear or shelter for the swampy sub-Arctic boreal forest, they would likely be dead or close to it.

Though there are black bears, polar bears and wolves in the area, Arama said it was the insects that would "eat them alive".

"They won’t stop biting until until your eyes close and you can’t see no more. Or, if you get enough bites you can go anaphylaxis and then end up in a serious life-threatening reaction."

Arama said the water would also be full of parasites and disease.

"I’ll be honest. With 40 years of experience, if you threw me out there with no knife, no tin can, no flint to start a fire, no tarp, no nothing, I’d rather die.

"This is no Crocodile Dundee movie. This is real."

Manitoba RCMP Assistant Commissioner Jane MacLatchy confirmed there would be phased withdrawal of most officers involved in the search over the coming days. A reduced police presence will still remain in the Gillam area.

"I know that today's news is not what the families of the victims and the communities of northern Manitoba wanted to hear," Manitoba RCMP Assistant Commissioner Jane MacLatchy said on Wednesday.

"But when searching for people in vast remote and rugged locations, it's always a possibility that they're not going to be immediately located.

"The terrain in northern Manitoba is immense. It's unforgiving. The weather is often very unpredictable.

"Additionally, there remains a possibility the suspects had some sort of assistance to flee the area."

McLeod and Schmegelsky are suspected of embarking on a killing spree two weeks ago in Canada's western province of British Columbia by shooting dead Mr Fowler, 23, from Sydney, and his North Carolina girlfriend, Chynna Deese, 24, on a remote highway.

Four days later, on another BC highway, the teenagers allegedly murdered botanist Leonard Dyck and then drove 3000km east across Canada's north to Gillam where on July 23, they dumped and then set fire to their car.

Along the way they had peaceful encounters with a petrol station attendant, a safety officer on a alcohol checkpoint, and a man who helped them after their vehicle became stuck in mud.

All three did not realise at the time McLeod and Schmegelsky were fugitives.

MacLatchy denied the RCMP in Manitoba took too long informing the public, telling reporters within an hour of discovering the teens might be in Manitoba, they alerted the public via Twitter.

The withdrawal of resources will come in phases over the next week.

"To be clear, we are not ending this search," she said.

"A number of tactical resources and specialised assets will remain positioned in the Gilliam area, and will continue the efforts to locate the murder suspects."

RCMP search teams had dogs attempting to find their scent but MacLatchy said she was not sure if the dogs were trained to find dead bodies.

"It's just a very tough place to find somebody who doesn't want to be found," MacLatchy said.

2. Borce Ristevski's sentence to be challenged in November.

A bid to increase the jail term handed to Melbourne wife killer Borce Ristevski will be considered by Victoria's Court of Appeal in November.

Ristevski was jailed in April for at least six years after admitting the manslaughter of his wife, Karen, but with time already served he could walk from prison on parole in December 2023.

An appeal by Director of Public Prosecutions Kerri Judd QC against the maximum nine-year sentence is set to be heard on November 13.

Karen Ristevski's body was found covered in twigs at Macedon Regional Park, northwest of Melbourne, eight months after she went missing in June 2016.

Her husband killed her at the couple's Avondale Heights home before bundling the body into her Mercedes-Benz and playing a mournful pallbearer at her funeral.

Ristevski had been due to stand trial for murder but a court deemed there was insufficient evidence to secure a conviction and he pleaded guilty to manslaughter.

Prosecutors vowed to challenge his jail term, labelling it "manifestly inadequate".

3. Student sentenced for killing "terrified" echidna.

Chinese university student Zhenbo Gao has been captivated by Australia's native wildlife since the moment he set foot in the country almost three years ago.

By day, he studied event management at Brisbane's Griffith University but at night, the 24-year-old prowled the Nathan campus in search of animals he could only find here. He took pleasure hunting lizards, petting possums, chasing koalas and gave a wide berth to a passing goanna.

In May last year, in an isolated stretch of campus, he finally came across a creature he had only ever read about - an echidna.

Gao couldn't resist picking up the spiky mammal, but dropped it when he was pricked by it's sharp spines. He grabbed hold of it a second time, and hurled it from a bridge to see if it could survive.

It did, barely.

The injured echidna crawled away, trying to escape by balling up under a ramp and burying itself in the dirt to hide. Gao threw rocks the size of a football and used a stick to prize the injured mammal into the open before it died.

An autopsy report revealed the "terrified" echidna suffered significant pain and died from blunt force trauma.

Gao told RSPCA inspectors he had never seen an echidna before and was "curious", tossing it from the second-storey height to see if it would outlast the fall. He claimed he never intended to kill the animal, but wanted to take it home and study it.

That curiosity cost Gao, who pleaded guilty to animal cruelty during a Holland Park Magistrates Court hearing on Wednesday. Defence lawyers told the court he was "deeply remorseful" and had brought great shame to his family.

Gao's mother travelled from China to support her son but was "disappointed and shocked" by his behaviour. In a reference tendered to the court, she said his curiosity meant he did not always make the best decisions.

He was spared a recorded conviction, but ordered to serve 18 months probation and carry out 180 hours of community service. He was also banned from keeping an animal for five years and ordered to pay restitution to the RSPCA, which was bitterly disappointed by the sentence.

"Sometimes we question what exactly you have to do to an animal to end up in jail," RSPCA spokeswoman Tracey Jackson said.

"This was a defenceless animal. There was no explanation for what was done to the animal except sheer curiosity and, quite frankly, that is alarming."

4. Victorian police considered arresting informer, Lawyer X.

Victorian police considered arresting lawyer, Nicola Gobbo, when she defied police orders and continued to represent a drug cook client she turned in.

Instead hey put her in "babysitter mode", telling her they wouldn't accept any more intelligence and that nothing she was continuing to share would be acted on. Until she told them what she knew about what was then the world's biggest ecstasy bust — importing 4.5 tonnes of MDMA in tomato tins from Italy.

Her tips led them to Rob Karam, a drug trafficker now hoping to appeal his 35-year prison sentence because of Ms Gobbo's involvement in his conviction.

Ms Gobbo was recruited for her third stint as a police informer in 2005, but just seven months later she was put on ice for turning on a client and continuing to represent him.

Tips that came from her social connections were "fair game" and her relationship with the cook was "very, very social", "Sandy White" a former officer involved in handling Ms Gobbo revealed.

It was a conflict of interest, but that was a matter for her, he told an inquiry into police use of informers.

"I don't think somebody represented by a barrister, who goes and tells that barrister about cooking in a clandestine lab or importing 4.5 tonnes of MDMA is in a position to be too upset about that," he said, defending the actions of police using a lawyer against her client.

But he admitted arresting her to end the conflict was an option.

"It did cross my mind that might be an option, but there's no powers of arrest for a conflict of interest and I didn't think it would be sufficient to justify an arrest for a perverse of the course of justice," he said.

Mr White said he had no issue with Ms Gobbo's information and the only problem with the cook was that she continued to represent him.

"She didn't do that for anyone else," he said.

But counsel assisting the commission Chris Winneke QC disagreed, pointing to the prison release of Faruk Orman on Friday.

Mr Orman was acquitted of murder by the Court of Appeal, which determined Ms Gobbo caused a "substantial miscarriage of justice" by representing both him and the key witness against him.

The inquiry also heard directly from Ms Gobbo for the first time on Wednesday, when recordings of conversations between her and Mr White were played.

Officers denied Ms Gobbo was being recorded then, but would be in future.

"I'm very concerned about that ... once something's recorded, it's there," Ms Gobbo said.

He tried to reassure her, saying only she and the officers in the room would know they existed.

The royal commission is examining the force's use of informants and its recruitment of gangland barrister, Ms Gobbo.

5. Casino company Crown denies dodgy dealings.

Casino giant Crown has hit back at claims of dodgy dealings including money-laundering and instead says it's facing a "deceitful campaign".

"Much of this unbalanced and sensationalised reporting is based on unsubstantiated allegations, exaggerations, unsupported connections and outright falsehoods," the statement released on Wednesday showed.

The statement, which was released as an advertisement, on behalf of the Board of Directors which includes John Alexander, former AFL chief executive Andrew Demetriou, and former politician Helen Coonan.

The statement also hit out at reports Crown turned a "blind-eye" to money laundering and said it was bound by non-disclosure provisions in the legislation.

"Crown is therefore constrained in responding to many of the unfounded allegations made in the media reports."

It also rejected claims it dodged Australian visa application requirements for wealthy clients.

"Crown has not sought to circumvent visa requirements or compromise any process of identification or verification for immigration purposes."

The gambling giant has also hit out at the assertions made about "junket operators".

"Crown deals with junkets and their customers in essentially the same way as other international casinos," it said.

Nine News published a series of reports alleging large sums of cash were being processed at Crown's Melbourne casino, and that special deals with government were granting foreign high-rollers easy access to the nation's gaming rooms.

In one instance, it was alleged that a wanted criminal was able to touch down in Australia in his private plane and took off, despite being subject to an Interpol notice.

Federal parliament heard calls for a parliamentary inquiry on Monday.