Domestic Animals Services said members of the public have complained they don't feel safe having dogs at playing fields during games, even if those dogs are on-lead. A notice was sent to sporting groups earlier this week urging them to remind dog-owning spectators of the legislation.

Dogs are not permitted at any time at enclosed ovals or synthetic grounds, and are not permitted at unenclosed grounds when sport is being played or formal training is taking place, the letter sent to sporting clubs said.

Dogs are permitted on unenclosed ovals when the oval isn't being used for organised sport.

The fine for taking a dog into a prohibited area is $150.

Wests Junior Rugby Club posted the letter to their Facebook page with the message, "This is official and we can't use ignorance as an excuse as we have been asked to formally warn everyone. You will [be] fined on the spot. Please be aware...".

A Domestic Animal Services spokesman said there were concerns that dogs were not under effective control and not all owners were having dogs on leads.

"This means the dogs are able to roam around on and off the fields," the spokesman said.

"The concern with dogs being on playing fields is that sports events are community events and not all members of the public feel safe when dogs are close by. In addition, the risk of attacks on people and other dogs increases in such environments."

There were two penalty notices and three warning infringements issued in the past 12 months, but 52 reports of dogs off-leash in prohibited places.

The spokesman said rangers had focused on educating owners about the issue.

"Domestic Animal Services rangers always exercise their discretion when dealing with members of our community. Domestic Animal Services tries to educate owners, however sometimes stronger enforcement action is warranted in the minority of situations," the spokesman said.

Rangers would be "highly visible" issuing infringement notices for dog owners doing the wrong thing, the spokesman said. Assistance dogs are exempt.

In response to the Wests' post on Facebook, James Kimber said his concern was the dog poo being left behind on playing fields.

Mr Kimber's daughter plays for Wests Rugby at Weetangera in the Under 16s team.

"If dog owners picked it up it wouldn't be such an issue," Mr Kimber said.

He said the team often trained behind the dead-ball line, and just because the poo was off the playing field wasn't an excuse for owners to leave it behind.

"It's weekly that me and the coach for the team have to put cones around dog poo that we see so the girls don't land in it," he said.

"I don't have a problem with people bringing their dogs there... It's that owners aren't picking up their dog's poo and at the end of the day if they did that, there wouldn't be a problem."

Mr Kimber hoped rangers would use discretion in fining people, particularly because most people tried to do the right thing by carrying plastic bags to pick up after them, and having their dogs on-lead and controlled.

"It's the minority, and the minority always spoil it for people who do the right thing," he said.