The Harris Hawk - Parabuteo unicinctus - formerly known as the Bay-winged Hawk or Dusky Hawk, is a medium to large bird of prey which breeds from the south western United States, south to Chile and central Argentina.

The Harris Hawk is famous for its remarkable behavior of hunting cooperatively in family groups. Most birds of prey are solitary hunters.

They have dark brown plumage, with chestnut shoulders, wing linings, and thighs, white on the base a tip of the tail, long, yellow legs and a yellow cere.

The bird lives in sparse woodland and arid regions, as well as wetlands including mangrove swamps, as in parts of its South American range and are permanent residents, they do not migrate.

The diet consists of small creatures including birds, mammals, lizards and large insects. They take larger prey when hunting in a "pack".

They nest in small trees or cacti. The nests are often compact, made of sticks, plant roots, and stems, and are often lined with leaves. They are built mainly by the female. There are usually two to four white to blueish white eggs. The nestlings start out light buff, but in five to six days turn a rich brown.

Since about 1980, Harris's Hawks have been increasingly used in falconry and are now the most popular hawks in the West, as they are the easiest to train and the most social.

There are many businesses that thrive during the fortnight of the Wimbledon tennis championships.

However, few of the many catering or hospitality firm employees working at the south London venue for two weeks are prepared to work for scraps of dead mice or quail.

As the All England Club staff prepare the world-famous grounds for each day's new play, look skyward and you will see another member of the team hard at work.

Rufus is a Harris Hawk who even has his own pass allowing him access to the All England Club.

His job is to clear Centre Court and the surrounding area of the pigeons, tempted by discarded food, who might become a nuisance during the tournament.

Rufus is a high-flying employee of Avian Control System, a Northamptonshire based company founded by Wayne Davis.

Mr Davis, 46, got his first bird of prey, a kestrel, when he was an eight-year-old boy living on a housing estate in Corby.

But it wasn't till the owners of a nearby flour mill one day noticed the effect his birds had on the local pigeon population that he realised there might be a business application for his schoolboy passion.

His firm has now been in business for 13 years, keeping pigeons off factories, landfill sites, hospitals, and other places of work that might be plagued by birds.

And that commercial road led all the way to the All England Club in the south-west of the capital.

For years, stray pigeons fluttered on to Wimbledon's prestige court at major moments, distracting players and disrupting the tournament.

As anyone who lives in, or visits, London will tell you, pigeons in the capital are not easily shooed away and proved unimpressed by officials waving their arms at them.

But their attempts did catch the attention of Wayne's wife, Donna.

"She was watching the tournament on television and saw games being disrupted by pigeons," recalls Mr Davis.

"So she got in touch with the Wimbledon organisers and they liked her idea of bringing in one of my birds to keep pigeons away."

A phone call from the All England Club to Mr Davis followed, asking him to come down for an interview which led to his unusual job.

He has been going back for the best part of a decade now.

Falconry is a centuries-old pursuit, but this medieval technology has proved superior to modern alternatives.

And even though this year's pigeons are unlikely to have ever seen an American Harris Hawk before, their instinctive fear of the hawk's shape succeeds in scaring them off where other techniques have failed.

As Mr Davis explains, for the company, it's not just a fortnight's work.

"My bird is flown around the Wimbledon complex early in the morning on three days a week during the tournament," he says.

"It has to be done when there are not many people about, and the hawk has to be 'off-court' before midday when play starts on the outer courts," says Mr Davis.

"He does not kill pigeons, but his presence is enough to frighten them away. It is a deterrent, and an environmentally friendly and unobtrusive way to keep the courts clear.

"I actually visit the site once a week right round the year, as the pigeons do not register the hawk's presence in their memories for very long and it needs a regular presence to keep them away."

Birds can present other problems which have expanded the workload for Rufus and his colleagues.

In his office, a young barn owl dubbed Floccus (the meteorological term for a fluffy white cloud) hops around from drawer to computer keyboard, his white down giving way to feathers.

He is getting used to the company of human beings before becoming part of the workforce.

His job might not be pigeon-scaring duties at Wimbledon, but as part of the team as they go round the country to schools and fairs, showing that the ancient British tradition of falconry is flying high and working hard.