Rouser co-founder and creative director Rob Beamish commissioned Sydney-based artist Louis Pratt to create the bust with the intention of it ending up on the Prime Ministers Avenue.

"We aim to blur the lines between entertainment and activism to get more attention," Mr Beamish said.

The bust was only on display for a couple of hours on Monday morning, before being removed.

Mr Beamish has worked in advertising and within activism groups in the past.

"Sometimes stories are not told in a very interesting way," he said.

"It is all about getting conversations happening and having people engaged."

Before landing in Ballarat, the bust has travelled around Melbourne, including Federation Square and the Brighton Beach Boxes.

Friends of Ballarat Botanical Gardens president Terry O'Brien said although the latest display was "fairly harmless", the avenue needed to be respected.

"Generally this is fairly harmless," Mr O'Brien said.

"The busts convey factual information about the past and we can walk down the avenue and see the leaders that have allowed Australia to remain a democratic country since 1901."

He said it was important to remember the Prime Ministers Avenue was an open art gallery.

"It is an important component of our much loved and admired Ballarat Botanical Gardens," Mr O'Brien said.

"The other reason we need to show respect is because these are works of art. Sculptors have put blood, sweat and tears into their creations."

EARLIER, 10.50am: A bust of Prime Minister Scott Morrison has suddenly appeared in the Ballarat Botanical Gardens.

The seemingly unsanctioned bust, made from coal and resin, has emerged along the Prime Ministers Avenue.

It has been placed along the section of the avenue where the next Prime Minister's bust would likely be erected.

The Courier inspected the bust on Monday, which appears to be hollow and easily moveable.

It follows the style of size of the other existing busts.

The statue appears to be the same one that has been unveiled as part of a collaboration between Sydney-based artist Louis Pratt, political activist group GetUp and climate-focused creative agency Rouser, according to Pedestrian TV.

It is certainly not the first time pranks or graffiti have plagued the Prime Minister's Avenue.

In 2017, pranksters adorned Tony Abbott's bust with a crown of onions in reference to the time he bit into a raw onion in 2015.

There was also a more sinister attack on the busts in June, 2020.

On that occasion, Mr Abbott's bust was once again vandalised, as was former Prime Minster John Howard's.

That particular attack was widely condemned and came at a time when historical statues throughout the world were being questioned.

The bust of former Prime Minister Kevin Rudd was also once draped in a dress.

The iconic Prime Ministers Avenue showcases a collection of 28 bronze busts dating from federation.

They cost about $30,000 each.

All Prime Ministers feature, except for Malcolm Turnbull and Scott Morrison.

However, Malcolm Turnbull's is yet to be unveiled and if Labor wins the federal election on Saturday, the avenue will fall further behind.

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