Maylands MLA Lisa Baker said it was estimated that more than 60 cats had lived at a Caledonian Avenue address, bothering the neighbourhood for more than a decade.
She said the home was one of two in Maylands where pet owners kept well in excess of the permitted number of cats.
With no limit on the number a person can own under the State Government Cat Act, the City of Bayswater developed its own local law to deal with the issue.
The Keeping and Control of Cats Local Law came into effect in October 2014 with an amnesty period until the end of February 2015.
Since March 1 2015 residents with unregistered cats risk a $250 fine.
Mayor Sylvan Albert said the Act gave rangers the authority to enforce the new laws but could not be applied retrospectively.
�Under the Keeping and Control of Cats Local Law residents are allowed to have a maximum of three cats unless approved otherwise,� he said.
�Under the new rules cat owners may apply to the City for a permit to have more than three cats on a single dwelling, to a maximum of six or when they wish to have more than two cats on a multiple dwelling.�
Ms Baker said since the law came into effect, an increasing number of kittens and young cats were living at the Caledonian Avenue home.
Caledonian Avenue property owner Helene Fung said the number of cats was especially problematic when they were in heat.
�They�re really noisy and they leave a lot of cat droppings on the roof,� she said.
�The stench of cat urine and droppings in summer is really strong.�
Cr Albert admitted there had been �some� properties where cats had been seen in excessive numbers but said there was no evidence that more than the prescribed number were housed at any particular premises.
�The City is carrying out extensive trapping in the associated areas,� he said.
�The City takes nuisance of cats very seriously.
�Since April 2014 the City has trapped 208 cats that have been found in a place without the consent of the owner. The demand for cat traps has reduced, implying that the new rules are resulting in lower numbers of stray or trespassing cats.�
If residents have issues with cats trespassing on their private land without consent they should contact the City�s rangers and security services on 9272 0972.
The City received 374 Action Requests with regard to cats since April 2014.
The City of Bayswater owns 24 cat traps that are placed onto private land following Action Requests.
Many cats have been trapped reducing the number at some of the properties complained about.
Complaints involved large numbers of cats on one premises, resulting in health issues, cats fighting, cat nuisance and cats defecating on other people�s properties.