Evidence is growing that Britain’s naturalised parrot, the ring-necked parakeet, is beginning to cause significant problems both for humans and for other wildlife because of its remarkable growth in numbers.
The first major scientific inquiry into the parakeet’s impact has established what is thought to be the first true picture of its population: from an initial nesting in London in 1969, there are now thought to be 32,000 birds, nearly all crowded into the London area and the South-East – and they are increasing at the astonishing rate of 25 per cent a year.
The inquiry, being carried out by Imperial College, London, has received details of various damages parakeets are now doing, including to gardens, church spires and even a vineyard. Perhaps even more significantly, concern is growing about a roost of 4,500 of the birds at Stanwell, close to Heathrow Airport, raising the possibility of collisions with aircraft taking off and landing.
In terms of impacts on the natural environment, initial research is indicating that the parakeets may be outcompeting other birds at garden feeding stations, although there is no evidence yet that they are displacing other species such as nuthatches from their nest-holes – which appears to be happening in continental Europe. However, there is concern in London’s Royal Parks, such as Richmond Park, that the parakeets’ consumption of tree seeds such as beech mast and sweet chestnuts is now so great that it may be depriving the parks’ deer of essential food.
First greeted with surprise and delight as brilliant green exotic visitors to the suburbs of South London and Surrey, the parakeets have started to seem less welcome in the last few years with the explosion in their population – for in their tropical home range, from Africa to the Himalayas, they are widely considered to be pests, devouring large amounts of fruit and crops.
Last year, as revealed in The Independent, the Government made Psittacula krameri officially a pest in Britain, joining it with gulls, crows and magpies on the short list of birds which can be legally shot without special permission if it is causing problems.
However, last year’s action was largely precautionary, and there was no substantial body of evidence of extensive parakeet damage. Yet this is starting to emerge as part of an intensive survey of British parakeet behaviour – Project Parakeet – being carried out by Imperial College researcher Alexa Lord and PhD student Hannah Peck.
The work of Dr Lord and Ms Peck is concerned with establishing scientifically how far the parakeets are impacting on British native wildlife, and one of its initial results has been to get the first detailed picture of their numbers and distribution.
The birds can be counted when they gather for the night in large roosts, sometimes holding several thousand birds, and ten such roosts have so been identified (click here to see the map of the ten parakeet roosts) – nine of them in the southern and western suburbs of London and nearby Surrey, and one outlier in Thanet at the eastern tip of Kent. The largest found so far is of an incredible 15,000 birds at the village of Hersham in Surrey.
The research has shown that the parakeets, which are hole-nesters, do not yet seem to be driving other birds such as woodpeckers and nuthatches out of their own nesting holes – although this has been a fear, and has been observed in Europe. A parallel inquiry being run in 20 London parks this winter by the British Trust for Ornithology and the Food and Environment Research Agency is also looking at this.
But there is evidence that the mere presence of the birds, which are loud and aggressive, seems to have an intimidating effect on smaller species at feeding stations, and further research will look at whether there is direct competition over food.
Yet perhaps the most fascinating aspect of the inquiry is the anecdotal evidenced which has come in of parrots affecting human interests – such as stripping the grapes from the vineyard at Painshill Park in Surrey, damaging the wooden roofs of churches at Bexley in Kent, and roosting in huge numbers close to Heathrow.
“We will be contacting organisations such as the Royal Horticultural Society and the National Farmers’ Union asking if anybody who has had damage done can get in touch,” Dr Lord said. “A lot of members of the public are now reporting damage to domestic gardens.
“We think it is important to do the reseach now, because the longer it is left, the harder the situation will be to control.”
Where the parakeets are causing problems
Painshill Park near Cobham in Surrey is a restored 18th century landscaped park and one of its attractions is its vineyard, which is small but engaging: it has 24 rows of pinot noir grapes, 11 rows of chardonnay and 36 rows of seyval blanc. The grapes produce wine, including a sparkler, which is sold in the park. Unfortunately, it is also close to the massive 15,000-bird parakeet roost at Hersham, and sometimes the birds descend on the vines and strip them bare. Mark Ebdon, the estate manager, says that Painshill can produce up to 5,000 bottles a year, but this may fall to 500 bottles when the parakeets get busy. “They seem immune to scarecrows, things that go bang, and other deterrents,” he says.
The parakeets have been a particular problem for south London churches which have roofs or spires of “shingles” – wooden tiles – as they chew holes through the tiles to nest inside. The Reverend Ann Uphill, Vicar of two Bexley churches, All Saints, Foots Cray, and St James’s, North Cray, has had problems with both. The birds chewed through into the spire at All Saints, eventually necessitating restoration with reinforced tiles; but they are still inside the roof of St James’s. “They also have an impact on the masonry – they knock bits of it off,” Miss Uphill said.
The roost near the airport
One of the biggest parakeet roosts is of 4,500 birds at Stanwell near Heathrow – the birds roost in the poplar trees in the playing fields immediately behind Park Mews, off Stanwell’s Long Lane. Dr Lord thinks this may present a risk of bird strike to incoming and departing aircraft – “the roost looks to be about 900 metres from the runway”, the said. A Heathrow spokeswoman said: “We are aware of the presence of the parakeets but it is not an issue for us at the moment.
Nobody knows for sure how the tropical species Psittacula krameri, which is sometimes also called the rosy-ringed parakeet, took up residence in Greater London: the bird’s British origins are shrouded in urban myth. One theory is that some birds escaped from the set of the movie The African Queen, starring Humphrey Bogart and Katherine Hepburn, which was part-shot in Isleworth Studios, Middlesex, in 1951. Another has the birds being released by ill-fated Sixties rock guitarist Jimi Hendrix. However they got out, it is virtually certain that the birds were escapes, and their first documented breeding in the wild was in 1969, After a slow start, they population began to soar.
They are not the only parrot species breeding in the wild in Britain: in recent years, monk, alexandrine and blue-crowned parakeets, beyond doubt escapes from captivity, have also bred and produced young, But the ring-necked parakeet is the only species to have flourished, probably because of its hardy constitution – it is found at up to 14,000 ft in the Himalayas.