The gull populations is growing in urban areas, the council says
Fake eggs are being offered to businesses by Cardiff council to cope with nuisance seagulls, as the breeding season starts.
When real eggs on rooftops are replaced with plastic imitations the gulls have fewer chicks to protect and so act less aggressively, said the council.
The city has one of the UK's largest herring gull populations and businesses are being offered the buy-in service.
Cllr Margaret Jones said it would reduce the chances of problems.
A council spokesman said it had contracts with 27 companies around the city, and the cost of the fake eggs ranged between £400 and £1,100 per roof each year.
"The cost is based on the roof area, the number of nests, labour materials, accessibility and so on," he explained.
The service has not been made available to residential homes, the spokesman added, because of the health and safety difficulties of accessing sloping roofs.
"Commercial premises have mostly flat roofs, and that's where the gull problem is at its worst," he said.
It is estimated there 2,750 nesting pairs of seagulls in the city, with numbers on the rise.
The council says the growth in urban gulls is encouraged by birds attracted by the vast amount of food on offer.
This is causing problems such as gulls creating noise, nesting on roofs, swooping to protect young and ripping open rubbish bags.
The seagull's breeding season runs from April until September, and gulls will return year-after-year to areas where they find food. They will also scare off other birds.
Cardiff council has produced an advice leaflet suggesting preventative measures which can be taken by businesses.
These include disposing of food waste in the council's green bio bags, which are collected in the morning, rather than black plastic bags which are collected in the afternoon.
The council said it will shortly trial a food collection scheme in areas of the city with the most reported cases of seagull nuisance.
Larger versions of kitchen caddies, solid plastic bins, will be placed at the kerbside for collection.
Cllr Margaret Jones said: "It is clear that the seagull population in Cardiff is growing, as are the subsequent problems associated with the birds.
"By making helpful tips and recommendations available by leaflet, through our website and via the pest control service, we are giving people the opportunity to lessen the chances of seagull nuisance."
GULL ADVICE FOR BUSINESSES
Make sure left over food is quickly cleared from outside areas
Dispose of edible litter in gull-proof hidden bins
Present food waste for collection in wheeled bins or similar containers not plastic bags
Discourage people from dropping food litter on the floor
Consider using parasols which "hide" food from seagulls
Source: Cardiff Council
Carol Yahia, who runs the Grange Lodge residential care home in Grangetown, Cardiff, has in the past been plagued by nuisance seagulls.
The home's 25 residents were prevented from sitting outside in good weather, she explained, because of the mess made of the home's rubbish bags by seagulls scavenging for food.
Mrs Yahia said she has now managed to cure the problem by switching from bin bags to solid bins.
But she added that at the height of the home's gull problems she would have considered paying for any measure that might deal with the birds.
"If the council convinced me that that was the right way to go then I would consider it," she said.
"If you have a problem with seagulls you'll consider anything that might help."
The service is being offered to commercial premises but not to residents.