The Friends of Lightning Swamp and Noranda residents have noticed an increase in cats stalking the perimeter of the 72ha ‘island’ of bush, as well as an increase in cats fighting in and around the site.
It is understood some residents have used traps to catch more than eight cats in recent weeks.
Friends of Lightning Swamp president John Williams said the group first noticed an increase in cat numbers when it held night walks at the end of last year.
Mr Williams said several feral cats lived at the reserve but were “way outnumbered” by domestic cats.
“We’ve encountered local cats fighting in the reserve and on the outskirts,” he said.
“They can do a lot of damage to a host of fauna – lizards, frogs, birds, even insects.
“It’s basically an island. It’s got to self-support itself and the fauna rely on the habitat; the impact of cats can have a long-standing effect on the bushland.”
The reserve has about 120 fauna species, mainly birds.
Mr Williams said they would consider carrying out trappings with the help of the City of Bayswater, which jointly manages the bushland.
“The trappings could work but what’s the point of trapping cats if they’re still allowed to roam at night and get into the bushland?” he said.
“A bigger awareness program needs to be started on the damage cats can do and how to better manage your cat.
“People are not doing the right thing by their cat or the local environment.”
Mayor Barry McKenna said feral cats were an issue and could pose major problems for native wildlife.
“The City carries out trappings of feral cats on a regular basis to make sure that native animals are protected,” he said.
He said the City had experienced a decrease in the number of cats impounded since cat laws were introduced, as well as a reduction in requests for cat traps.
He said the City urged all residents to register, microchip and sterilise their cats.