This year's duck hunting season in Victoria is in doubt after a prolonged drought has devastated waterbird numbers and bushfires are estimated to have killed more than 1 billion native animals.

Key points: Hunters have urged the Victorian Government to make a swift decision on the start of the duck hunting season

Hunters have urged the Victorian Government to make a swift decision on the start of the duck hunting season Opponents of duck hunting say the duck population has already been devastated by drought

Opponents of duck hunting say the duck population has already been devastated by drought The Premier says the decision-making process is still underway

Usually an announcement about the length of the season is made in early January, but a decision on this year's season is yet to be made. Last year, the season started March 16.

The ABC understands Environment Minister Lily D'Ambrosio is considering cancelling the season, while Agriculture Minister Jaclyn Symes wants it to go ahead.

Field and Game Australia chief executive Dean O'Hara said the government needed to make a decision as soon as possible so those wanting to take part could prepare.

"If [the Government] makes a decision on the statistics provided to them, [the numbers] clearly show there's enough waterfowl for duck hunting season in 2020," Mr O'Hara said.

"Our concern is if this becomes a political decision that goes beyond the evidence."

One of Victoria's state game reserves, Lake Connewarre, sits south-east of Geelong. ( Supplied: Field & Game Australia )

Sean Dooley, from Birdlife Australia, said he was hopeful there was debate going on within the Government about the viability of this year's hunt.

"There's been a 90 per cent reduction in waterbird numbers since the 1980s, and we've had an incredibly dry year this year, to the extent where pretty much the only standing water in eastern Australia is in Victoria," Mr Dooley said.

"Those wetlands that are left will have larger numbers of birds … many of the refugees [from drought] from further north.

"And [the ducks] just don't need this now, not after the dry conditions we've seen and not after the recent devastating fires. And for the psyche of Victorians, we don't need to see more wildlife killed."

Sean Dooley fears many of the waterbirds gathering in Victoria are "refugees" from drier states to the north. ( ABC Radio: Conversations )

It is estimated there were about a million waterbirds in eastern Australia in the early 1980s, but recent figures show numbers have dwindled to roughly 200,000.

The latest Aerial Survey of Wetland Birds in Eastern Australia showed wetland habitat was at its lowest level since surveys began in 1982.

Researchers from the University of NSW believe this has led to a decline in the number of ducks and their ability to breed.

Premier Daniel Andrews last week said the Government was still deciding on whether the season would go ahead, and denied there was anything untoward about the delay.

"There is a process that we go through every year," Mr Andrews said.

"This year is no different in terms of the process but we do have some unique features: fire, drought.

"That process is not yet concluded, [and] any suggestion that it has is simply wrong."

Government regulator cops more criticism

The internal Government debate comes as six videos have surfaced that appear to show hunters breaking the law by failing to quickly kill birds after they have been shot down and shooting at birds on the water, rather than in the air.

The footage, captured by animal welfare advocates, allegedly shows incidents at four locations — Cullens Lake, Lake Bolac, Lake Modewarre and McGlashin Swamp — between March 17 and 31, 2018.

The videos were given to the Game Management Authority (GMA), Victoria's hunting regulator, almost two years ago.

However, chief executive Graeme Ford said the authority was unable to pursue most of the complaints.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 45 seconds 45 s WARNING: DISTRESSING CONTENT The footage, captured by animal welfare advocates, allegedly shows incidents at four locations in March 2018.

"The video footage from the 2018 duck hunting season was reviewed by the GMA, Prosecution Services and two independent vets," Mr Ford said in a statement.

"It was determined that there was insufficient evidence to give rise of a reasonable prospect of conviction for all except one of those complaints. That one matter is currently being investigated."

Despite nearly two years passing since the evidence was handed to the GMA, the hunter involved still has not been charged.

The GMA has been criticised for its failure to enforce hunting laws and properly police hunters, with the Victorian Government at one time even considering shutting it down.

Manfred Zabinskas, who runs an animal rescue shelter at Trentham and rescues hundreds of ducks injured by hunters every year, said he frequently saw hunters doing the wrong thing.

Manfred Zabinskas and partner Helen Round care for birds that have been wounded by hunters. ( ABC News: Jessica Longbottom )

"I see shooters misbehaving, shooting ducks they shouldn't be shooting, leaving injured ducks in the water," he said.

"So we just spend hours a day gathering up the birds that need the urgent medical attention. In most cases they just need to be euthanased.

"While a lot of money has been spent on how we police the sport, there is no policing and that's part of the problem."

According to the GMA, 20 individuals have been found guilty for duck-season related offences since 2015 and the authority has issued 67 fines.

Dean O'Hara, from Field and Game Australia, said the vast majority of hunters did the right thing.

"If a small minority want to disobey and break the rules they need to be held to account," Mr O'Hara said.

Duck hunting is banned in NSW, Queensland and Western Australia, but South Australia and Tasmania have announced this year's hunts are going ahead as planned.