parrots ?

FROM THE BBC - see more on their wonderful website.......

How do parakeets survive in the UK?
WHO, WHAT, WHY? The Magazine answers...

A suburban parakeet in LondonParakeets are originally from India. So why are they able to survive - and thrive - here?
Bedecked with emerald green feathers and a rose-red beak, the ring-neck parakeet brings a touch of tropical glamour to suburban gardens in London and the South East. There have also been sightings in the North West and in Scotland.
How does a bird that looks more suited to warmer climes cope in the UK?
"They actually originate from the foothills of the Himalayas, so they don't need it to be that warm to live comfortably," says Andre Farrar of the Royal Society for the Protection of Birds.
THE ANSWER
Parakeets originate from the Himalayan foothills, so winters here are no problem
Eat berries, nuts and seeds, all of which in plentiful supply
Bigger than native birds, so able to compete for food and nesting space in tree crevices
In pics: Suburban parakeets Three factors influence whether a species can adapt to a new habitat - food supply, climate and competition with other species.
"From the evidence before our eyes, the answer to whether these birds have successfully adapted is clearly yes," Mr Farrar says.
The population numbers about 30,000 across London, and the RSPB estimates it will rise to nearly 50,000 by 2010. In the Big Garden Birdwatch 2006, the ring-neck parakeet was among the 20 most-sighted birds in London, seen in all 33 boroughs and jumping from 19th place in 2005 to 15th.
"There is a stable and reliable food supply in suburban gardens for their diet of seeds, berries, fruit and nuts. And there has been an increase in the number of people putting bird-feeders in their garden," says Mr Farrar.
But he pooh-poohs any suggestion that global warming might have something to do with the population explosion. "They're long-lived birds and in the 40-odd years that they've been here, they have survived some quite cold winters."
He puts the boom down to natural population growth - there are more birds to breed and so produce more chicks.
Foreign invaders
The Government is currently developing a framework for dealing with non-native species - such as the parakeets, Chinese mitten crabs and grey squirrels - and assessing the impact on native species to these shores.
WHO, WHAT, WHY?

A regular part of the BBC News Magazine, Who, What, Why? aims to answer some of the questions behind the headlinesAs yet, there is no strong evidence that the parakeets are adversely affecting native birds that share similar habitats, such as starlings and woodpeckers. But if the growth of wild parakeets continues at its current rate, there are concerns that they could become a pest to farmers or threaten other wildlife.
"Competition for resources would be the main threat," says Mr Farrar. "This is a much wider issue, both in the UK and globally."
The introduction of invasive non-native species is one of the main causes of biodiversity loss worldwide, second only to the destruction of habitat.
There are a number of sometimes fanciful theories as to how parakeets came to make their home here, such as the urban legend that the birds escaped from a container at Heathrow airport, or from Shepperton Studios in west London during filming of The African Queen in 1951.