Edmonton is officially Canada's magpie capital, and the magpie numbers are still growing, according to a biologist with Bird Studies Canada.

Magpie numbers have been going up in Edmonton for five years, Dick Cannings with Bird Count Canada said on Tuesday.

Unlike most Canadian bird species, which have seen numbers dwindle over the past 40 years, magpie numbers are stable, and have actually gone up about 20 per cent in Edmonton over the past five years.

"Edmonton is one of the real centre points for magpies."

The announcement comes as no shock to Shannon Melanson, who lives in Edmonton's Strathearn neighbourhood. Melanson says the birds have made a habit of attacking her cat, Marley.

Shannon Melanson was joined by her daughter Maddie, 3, on Edmonton AM on Tuesday to talk about some of the problems their cat has been having with the local magpies. (CBC) Melanson says the trouble started last spring, about a year after the family moved into their home.

"It starts when they do their nesting and they start getting aggressive and then when the babies are born," Melanson said.

"They squawk — they get down and do that 'Eh! Eh! Eh' right in her face and they chase her around the decks, around the property until she comes back inside. So she's pretty scared of them."

After being terrorized by magpies and getting chased from the family yard, Marley went missing for three weeks.

When the cat came back, the family started keeping her inside during the spring when the magpies are nesting. But even indoors, the magpies haven't left Marley alone, she said.

"When the windows are open and she's sitting on the window sill, they'll sit on the fence and squawk at her and they don't leave her be.

"She's a pretty tough cat … but these magpies are aggressive."

Melanson called the city to complain and see what can be done, but says she was told animal control doesn't deal with magpies.

Edmontonians are allowed to trap pests — including skunks, porcupines, squirrels, ground squirrels, crows and magpies — that are causing trouble on their property.

However, while the city provides traps for porcupines, skunks and squirrels, it doesn't do the same for magpies. Instead, homeowners are expected to build their own traps using instructions from Alberta Agriculture.

"That's not really something I'm interested in doing," Melanson said.

Keep your cat indoors, advises expert

Canning said stories like Melanson's are common — especially in the spring and summer, when young birds hatch and leave the nest, essentially doubling the city's magpie population for a period of time.

"I'm not surprised they attack cats, because magpies are intelligent and they know what cats do — and cats kill birds," he said.

"The young are screaming because they're hungry, the adults are screaming because they see cats and people that they want to defend their young against."

To avoid trouble, Cannings recommends worried pet owners keep their animals indoors while the birds are at their loudest and most aggressive — usually in June.

"Like most birds, a lot of them die off quickly by various misadventures, and so by next spring you're back to the same number"

A spokesman for animal control with the city told CBC News that magpie culling measures were in place until about 10 years ago, but the policy was cancelled when it was deemed ineffective. Today, the city does not do anything to control the magpie population.