The RSPCA is again calling for bow and arrow hunting to be banned after an emu was spotted with an arrow sticking out of its rump near Port Lincoln this week.

Department of Environment rangers are still trying to find the emu around the Tulka region, south of Port Lincoln.

Local Robyn Pedler was driving to work when she noticed the arrow sticking out of the emu when the bird was taking a dip in a water pool.

She was trying to take a photo when the emu got up and gingerly moved off into thick scrub.

"It wasn't running fast like emus can and do, that we witness quite often in that area," she said.

"It was very … apart from being distressed on behalf of the animal of course, it's a very distressing human response as well."

RSPCA South Australia animal welfare advocate Rebekah Eyers said similar shootings had been on the increase around Australia.

She said the State Government had failed to stamp out the barbaric practice.

"The animal is injured and it dies a prolonged and usually extremely painful death," Dr Eyers said

"Animals that have been found this way, often the wound site has been infected, the animal has been extremely dehydrated and it's incurred serious organ damage.

"This can go on for a long time, so it's a prolonged death and it's very, very painful."

Still searching for distressed bird

Ms Pedler contacted the Department of Environment, Water and Natural Resources (DEWNR) to report what she had seen.

The department sent out the duty ranger and together they walked through the scrub trying to find the emu.

While they spotted it, the ranger who was carrying a gun to euthanise the bird was unable to get a clear shot.

Ms Pedler said she was told if the bird was not euthanised, it would "face a slow, painful death", so she hoped the person who shot it could be found.

"This is very distressing to see what behaviour humans [inflict] on our native animals, and this is not fair and it's certainly not legal," she said.

"It's harmful and it's torture of an animal."

The RSPCA says animals shot by arrows face painful deaths if they are not treated. ( Supplied: Australia Zoo Wildlife Hospital )

Rangers concerned by shooting

Ranger-in-charge Ron Sears said it was a worrying situation.

"It's of great concern for us because [of] defenceless animals like the emu. We're concerned what people are doing and what they're using to do that just for fun," he said.

Mr Sears said if the emu was found it would have to be euthanised humanely because it was difficult to deal with adult emus.

He hoped when the emu was found the arrow could be retrieved, because the department could use it as evidence to try and find the person who shot it.

They could then be charged under the National Parks and Wildlife Act, which carries fines up to $2,500 and up to six months in prison for people found guilty of causing injury to native protected species.

Not an isolated incident

The shooting of the emu is not an isolated incident, with other cases in South Australia and around the country this year.

A cat was shot four times with a bow and arrow in the Adelaide Hills in July, and in Darwin, a pony was fatally shot by arrows last week.

And in Port Lincoln in 2013, the Rough family returned home from a weekend away to find their pet baby alpaca in distress and limping from an injury to its back leg.

Kristen Rough holds her family's pet alpaca as it receives treatment from vet David Oswald. ( Supplied: Vets on Eyre )

They took it to the vet for treatment and staff found a thigh wound that was five inches deep.

Later, a neighbour mentioned seeing three teenage boys carrying what looked like a hunting bow, and they realised the wound was from an arrow.

"We never found the arrow on our property and obviously it wasn't left in the alpaca, so whoever had shot it had jumped into our premises to retrieve it," Kristen Rough said.

"This is absolutely a concern. We live within the city limits.

"If we were at home and it had hit our child or anyone else who happens to walk around the area, it could have been a far worse outcome."

State Opposition doesn't support ban

The State Opposition said it doubted a ban on bow and arrow hunting would have much of an impact on animal suffering.

Shadow Attorney General Vickie Chapman said a ban would be simplistic.

"Banning a particular mode of weapon is not going to be the answer … if there's no clean kill then it would be reasonable for a responsible citizen to ensure the domestic or wild animal actually is put down," she said.

"Someone using an injection can inappropriately cause long suffering to an animal, or shooting it, and so simply identifying a bow and arrow and banning it, it may be a simplistic band-aid to the distress that's been caused, but it's not a way to make law."