Thieves broke into the guinea pig enclosure at the park two weeks ago and stole about 20 baby guinea pigs, leaving their parents behind.

The theft occurred after hours.

Warracknabeal Lions Club president Maurie Parsons said it was the first time such a large number of guinea pigs had been stolen.

"We have had two or three guinea pigs go at different times, but this is the biggest lot," he said.

"People only have to ring someone at the Lions club and we will give them a guinea pig.

"Some give us a donation and some don't.

"It's just disappointing that this is happening; vandals are wrecking the facilities.

"This is the society we live in at the moment.

"They even wreck the play equipment.

"We are all volunteers and we don't have that much money to keep on repairing the facilities."

The stolen baby guinea pigs were due to be in an animal nursery at the Warracknabeal Agricultural and Pastoral Society Show on October 11.

"The society usually takes half a dozen guinea pigs over there and gives them away to people who want them at the end," Mr Parsons said.

"It's good publicity for the show."

Warracknabeal First Constable Teilah Morrissey, a guinea pig owner, said the vandalism and theft had left people angry and disgusted.

"The park is a community-run organisation, so volunteers look after all the animals and repairs," she said.

"So whenever someone vandalises the facilities, it takes money out the town.

"This is not the first time the enclosure has been damaged."

First Const Morrissey said anyone with information could call Warracknabeal Police Station on 5398 1044 or Crime Stoppers on 1800 333 000.