The urban jungle -- What happens when animals go wild in the city

Perching on the side of an old power station chimney with St Paul’s Cathedral to the north and the Shard, Europe’s tallest building, to the east is not where you might expect to glimpse the world’s fastest bird. Yet Tate Modern, and London landmarks including Battersea Power Station and the Houses of Parliament, have been home for several years to peregrine falcons. A surprising flash of the wild in the heart of the city, the powerful bird of prey is also a specialised hunter of feral pigeons, considered such an urban pest that in 2003 a ban was imposed on feeding them in Trafalgar Square.

With cities’ abundant food sources and tall buildings providing a predator-free equivalent of the species’ traditional cliff-side home, the raptor’s success has extended far beyond the capital. Having colonised urban areas from Aberdeen to Cardiff, ecologists now believe it is only a matter of time before peregrine falcons are breeding in every major UK town and city.

“All those born and bred in cities, that’s their habitat that they’ve grown up in. When they’re drifting around the country, they find little towns and cities elsewhere … and that’s what they’re used to,” says David Goode, a veteran ecologist and author of a new book, Nature in Town and Cities. “That’s why I say it won’t be long until they’re in every place.”

The peregrine is just one of many species that have invaded British cities in the last few decades, encouraged in no small part by an urban ecology movement that flourished in the 1980s. “There are those that have done well – pigeons, foxes, gulls – because of our food,” says Mathew Frith, an ecologist and policy director at the London Wildlife Trust. “There are others that have done well without our intervention, such as the black redstart, known as the ‘bombsite bird’ because of its liking for the cover that bomb sites provided.” Then there are the species that benefited from conservation efforts, such as the red kite.

A large bird of prey with a wingspan of nearly two metres, the kite was on the verge of extinction until a wildly successful reintroduction began in 1989. Today there are more than 1,000 breeding pairs in the UK. Frith believes that with kites recorded flying over Hackney, they could be breeding in London in as little as a decade as they expand from existing strongholds, such as Reading. They can also be seen in Leeds city centre, Gateshead, Manchester and Birmingham. It is a long way from past expectations of naturalists. In 1898, ornithologist William Henry Hudson thought it “exceedingly rare” that such raptors would ever return to our cities, following decades of industrialisation and urbanisation.

In the Midlands in particular, the urban wildlife movement grew as industrialisation went into reverse, and nature recolonised derelict land. And it happened despite, not because of, the traditional big conservation groups. “There was a big sand quarry in Birmingham which had wonderful wetlands and great sand cliffs. The local authority in the late 1970s decided it would be a useful landfill site, which triggered very local opposition,” recalls Chris Baines, vice-president of the Royal Society of Wildlife Trusts since 1984 and an ecological adviser to several major developments including the Thames Tideway tunnel.

“The landscape was teeming with newts and frogs but people realised in official circles that didn’t count for anything. The RSPB famously wrote to me to say it was very interesting but there can’t be anything there because it was in the middle of Birmingham.” The site was eventually saved by local people and, in Baines’s retelling, “the penny began to drop” in nature conservation circles that they needed to connect with people, and most people lived in cities.

“This is not a second-rate [version of nature],” he says, as he counts off the owls and woodpeckers that live near his home in Wolverhampton. As Goode outlines in his book, the variety of our cities lends itself to a diversity of species. “Because the city is so heterogeneous, with a great mixture of different ecological conditions, it is not surprising that a considerable variety of wildlife is able to exist.”

In Edinburgh, kestrels hunt voles at Arthur’s Seat. Exotic species such as mandarin ducks and Egyptian geese are on the verge of colonising cities. Kingfishers have brought a splash of colour to grey concrete waterways in gritty urban areas including Deptford, south-east London, and one was even seen regularly in St James’s Park in central London this winter.

Badgers and foxes are now in most major urban areas, aided by a more regular food supply than they can find in the countryside. Deer crowd on city fringes, with numbers high enough in Richmond Park to necessitate a twice-yearly cull. Otters have rebounded and can now be found in every county, and have used waterside wasteland areas and canals to make their way to the heart of cities, such as under Leeds railway station.

Water voles – Ratty in The Wind in the Willows – can be found in Bristol and Newcastle, living happily free of one of their main modern threats, imported American mink. Like the kingfishers, both have been helped by cleaner waterways as the Environment Agency has cracked down on polluters, with the UK racing to meet EU water quality standards.

But this invasion has not been entirely peaceful. There are famously more foxes living in London than there are double-decker buses and, while some people love to see them and leave out food to entice them, others pay snipers to kill foxes for £75 per animal. When a fox reportedly bit off a baby’s finger in its Bromley home in 2013 – surgeons later reattached the finger – mayor Boris Johnson backed a cull of urban foxes, calling them “a menace” and subsequently joking that they could be hunted from bicycles.

Yet experts say fox numbers in the UK are relatively stable. Professor Stephen Harris of the University of Bristol, the authority on the subject, says there are around 33,000 urban foxes. Besides, ecologists argue, killing foxes would be pointless because they are territorial, with a territory of 25 to 40 hectares on average at the smaller end. Kill one, and another simply claims the territory. “Until you manage the food issue, any kind of control is kind of pointless and expensive,” said Frith.

Foxes aren’t the only wildlife that some people want to shoot. James Marchington, a gun sports journalist and owner of the “bird table of doom”, found himself under fire from conservationists last December for publishing a video showing how to shoot ring-necked parakeets in London.

Originally from Asia, the bright green birds have gone from a population of zero to more than 30,000 in less than four decades, and are now found in London, Manchester, Birmingham and Oxford. The invasive species has the potential to be a serious agricultural pest by stripping fruit crops – if it can successfully expand into rural areas from the urban strongholds it has colonised. In 2010, they were added to the general licence, a list of birds that can be killed without a permit if they are causing significant damage to crops.

“Though the critics of my video chose not to notice, I did have a specific problem with a small number of individual birds who’d taken a liking to the apple trees in my garden … as I understand it, that’s covered by the general licence,” said Marchington, who lives on the outskirts of London, in Surrey. “I’ve grown up surrounded by shooting in the countryside and wildlife management comes naturally to me; that’s what you do.”

The RSPB disagreed, condemning the video, which, it argued, showed a leafless tree without a crop and wouldn’t justify shooting under the general licence. Marchington, who keeps chickens and feeds birds in his garden, said “we are all hypocrites” when it comes to animals. He said the reaction to the video spoke volumes about conflicted modern attitudes to wildlife. “I think people today are disconnected to nature, and yet still have a hankering to get closer to nature. That manifests itself in people going hiking at weekends or doing bushcraft. But they find it difficult to reconcile this idea that they love animals, yet if we’re going to live the way we live [eating meat], they’re [animals] going to need to be killed and we’re going to need to manage wildlife populations [to be free of pests and diseases from animals].”

Animal welfare group Peta called the video “deranged”. Charlie Jacoby, who runs the channel where the video was shown, said in an interview: “Peta lives in this Disney world where all animals and birds are furry and cuddly. I like animals and birds as well but I also see them as pests and I also like to eat them. I think Peta needs to develop more emotional intelligence about wildlife. These birds are pests and government has designated them as such. People who live in towns should be able to manage their animal problems, just as people in the countryside do.”

Another section of society appears to view urban wildlife in a more practical, albeit no less destructive, light: as a potential meal. Ecologists in Sheffield report anecdotes of migrants living rough in the city’s parks catching fish to eat and roasting squirrels. They say eastern Europeans have the skills to catch and safely cook animals. A recent study by the Food Standards Agency and the Food and Environment Research Agency appears to back up those anecdotes, finding growing evidence that more people are eating fish they have caught from rivers and canals. “This may be partly due to the increased numbers of migrants from eastern Europe where this is part of traditional culture and partly because of a desire to try new foods encouraged by celebrity chefs,” the study concluded.

Ecologist David Goode says that while there is an occasional public outcry after isolated incidents of conflict, the British are accepting of urban wildlife on the whole. He attributes the live-and-let-live attitude partly to the country’s long history of conservation movements and amateur naturalists, right back to the city-based natural history societies of the early 19th century.

Another reason for that accepting attitude could be stressed-out city dwellers’ simple self-interest. Ecologists are at pains to stress the mental health benefits of nature in cities, while a major report by the environment department found the health benefits of living with a view of a green space are worth up to £300 per person each year.

Melissa Harrison is in no doubt she’d count herself among those benefiting mentally from being around urban wildlife. Brought up in semi-rural Surrey, she realised she was very unhappy while living in heavily built-up Dalston, east London, but couldn’t put her finger on the reason why. “I went to Devon for a week, and realised that was what I needed,” she said. “I moved south to Clapham – I had no garden but could see a tree out of the window. It had a magpie nesting in it, I could watch the leaves change, I had a connection.”

Inspired by getting a dog and moving next to Streatham in south London, she wrote a well-received novel called Clay about a boy and his connection with wildlife in the city. “Writing Clay was to get other people to notice [nature around them in the city]. You don’t have to move to Dorset, people have it here, they just need to notice it,” Harrison said.

“There’s just the simple fact that we evolved in nature, we’re animals, we’re not separate. You take us completely out of that environment and people feel it as a loss, that’s almost quite wordless. It’s the kind of thing you don’t necessarily notice you’ve lost.”

But the natural riches in our cities today shouldn’t be taken for granted, observers say. Previous gains could be set back by a combination of planning reforms, pressure for new housing, particularly in the south-east, and austerity measures. The capital has been losing the equivalent of 2.5 Hyde Parks a year to new developments and the paving over of front gardens, according to one analysis. Upcoming local government budget cuts of 10% for 2015-16 are “likely to have further adverse implications for biodiversity conservation”, warns the London Wildlife Trust, which says there has already been a “substantial impact” from previous cuts this parliament.

“The enthusiasm generated in the 80s is still resulting in things being done. But there is a degree of complacency creeping in now,” said Goode. He warns that local authority budget cuts will mean they will employ fewer ecologists, resulting in “a lack of ecological awareness in planning”.

Goode gives the example of former coal yard Camley Street, which is now a small nature reserve in the middle of King’s Cross after a campaign backed by Ken Livingstone and many others stopped it being turned into a coach park. “Nowadays, you wonder whether that kind of thing would happen. There are several instances of things being set up in the 80s, and everyone was full of enthusiasm. I wonder whether they would happen now.”

-- How wildlife is evolving in cities --

Falcons

Wildlife is changing our cities, but our cities are also changing them. Part of the peregrine falcon’s success has been learning to catch birds at night using artificial light, something they would not do in their traditional cliff and mountainside habitat. “That really is Darwinian evolution, a gradual shift of birds becoming aware of a new set of circumstances,” says ecologist David Goode.Those that excel at night hunting could thrive at others falcons’ expense.

Peppered moth

Biston betularia, a moth species, felt the impact of polluted UK cities in the 19th and early 20th centuries, with populations shifting from a white variety with black spots to a wholly black variety, which proved better in avoiding predators on sooty walls This is considered a classic case study of evolutionary pressures in action. But clean air legislation introduced in 1956 made the darker moths suddenly vulnerable in urban areas, leading to their decline. In Cambridge, the darker version is now effectively extinct.

Squirrels

Grey squirrels in cities are more likely to use visual rather than audio signals. US researchers say the behaviour may be a response to higher noise levels in urban environments, leading city squirrels to warn each other of predators using tail flagging more often than calls. Contrary to what scientists expected, urban squirrels were also more reactive to threats than their rural counterparts

Brains

Cotton mice and meadow voles in urban areas have bigger brains, US scientists have found, supporting the theory that the diversity and complexity of cities increases cognition, at least in some species. Other studies have also found that species with bigger brains fare better in cities. “It is logical to conjecture that brain size can be related to the success in an urban environment, which is both novel and harsh,” said the authors of a study of passerines, the largest order of birds.

Birdsong

Several studies have shown that city birds sing at higher pitches than their countryside cousins. A survey, by Rupert Marshall of Aberystwyth University, published in the journal Proceedings of the Royal Society B, found city great tits sing at a higher pitch than those in nearby rural areas to stand out over the lower-pitched rumblings of traffic and other man-made noise. Other studies have concluded that blackbirds sing at a higher pitch because they are able to sing more loudly at higher frequencies.