This is becoming a sort of regular news item ... some group discovers the guarding abilities of geese and it becomes a trend; mention is usually made of Roman precedent. Here's the latest exemplum from News.com:

GUARD geese are snapping at the heels of would-be burglars across back yards as home owners embrace them as family pets.
The birds, famous for saving the Roman Empire from a surprise attack by the Gauls in 365BC, have become part of honk-squads patrolling homes, car yards and council property.

Home invaders are being scared away by deafening shrills and the threat of attack by territorial geese that can weigh up to 15kg and have bills like serrated-edged knives.

Guard-dog trainer Chris Egan said goose ownership was booming as the birds, which fed on grains such as corn and wheat, were a cheap alternative to dogs.

"And they do the mowing," Mr Egan said.

"You better have friendly neighbours because they honk at anything.

"I would only recommend them on larger properties which have access to water and grass."

Brisbane-based produce agents say breeders are busy incubating hundreds of eggs of the slow-breeding birds to meet demand.

A rush on the low-maintenance family pets has led to shortages and recent hikes in the cost of the birds, which are fetching between $20 and $100 at pet shops and produce agencies.

Bridgitte Walls, of Capalaba Produce, said she was struggling to keep up with the demand for watch geese.

"We get no more than a dozen and they are gone within a few weeks," Ms Walls said.

"People like them because they are very good guard dogs, they are vicious and very protective."

Burpengary-based breeder Bob Whitehouse said geese were renowned for their savage nature, which made them excellent for security.

"They are certainly very good watchdogs. They can leave a nasty bite and have serration on the top and bottom of their mandible," he said.

He once owned a killer goose capable of tearing up swans and other large birds.

"I had to eyeball it and never turned my back," Mr Whitehouse said.

"The man who sold it to me was dead scared of it.

"He had to keep it in a brick house because it was killing the swans and birds on his property."

Geese owner David Green, of Durak, said the birds were also preventing theft at car yards.

"Just about anything will set them off," Mr Green said.

He said breeds such as toulouse geese were just like "cuddly labradors", but the bigger emden variety was capable of "clawing and biting" intruders.

"The toulouse will stand and hiss but won't chew your leg off," he said.

Goose trading has become a huge pastime on the Sunshine Coast, where there are pockets of semi-rural housing estates and families eager to find a pet.

Tina Crutchley, from Cedarton in the Sunshine Coast hinterland, said the birds were capable of "taking the top of your finger off".

The watchdogs of the bird kingdom have also gone on duty inside the fortified fenceline of whisky distilleries in Scotland and Ireland.

The big birds are used in the United States to guard defence-force property.

Brisbane residents have reported seeing geese on patrol at a council bus depot.

Given that Canadian Geese ... ostensibly a symbol of our country ... have generally become pests in many parts of Canada (heck, they don't even bother going south for winter any more), perhaps a roundup and/or sale of the noisy beasts would be something to ponder ...