The wildlife and green spaces in our cities, towns and other built-up areas matter.

They matter because as a nation we are increasingly being told that we are becoming disconnected from nature and that it is affecting our health, but not in a good way.

And who doesn’t get a good feeling from hearing a little bird chirping away, spotting bright flowers in the park, or stumbling across the signs of an otter on a walk along the river.

Land prices are ridiculously high, and pressure to develop is the greatest it’s ever been

Besides the influence nature has on our well-being, urban areas are one of the most biologically diverse habitats in the country. With more people living in cities than ever before, this diversity is increasingly coming under pressure: from building for accommodation and business, to people simply paving over their green spaces and cutting down trees.

Take London for example, with its population of over 8.6 million, it has had more than 13,000 species recorded (including 1,500 flowering plants and 300 birds), and according to the London Wildlife Trust’s director of policy and planning, Mathew Frith, it is the most species diverse region in the UK.

It’s a reflection of the city’s millions of gardens and its status as an international trading city, which has made it one of Britain's main points of entry for new species from elsewhere in the world. As a result ring-necked parakeets and Himalayan balsam have flourished and become as familiar as our native hornbeam and heather in the city's scenery.

And what many of us don’t realise, and may find surprising due to London's size and population, is that the capital holds nationally important populations of many species: stag beetles, greater yellow-rattle, black redstart and wintering populations of gadwall and shoveler, to name just a few.

There’s no doubt that the above species, and many more, need constant monitoring and protecting. The State of Nature report published in 2013 indicated worrying declines in lots of urban species, from birds to invertebrates.

But it’s a complex picture that continues to change according to Mr Frith.

Urban peregrine falcons are on the rise, greater spotted woodpeckers and jays are increasingly found in inner London and several species of deer are making their presence known. While the River Thames is now home to 125 species of fish after major clean-ups since the 1950s.

“There’s also been upswings for some species, either occupying new niches, or recovering from previous lows," Mr Frith explains.

“Some of this reflects national patterns; others are down to changes in London, either through targeted conservation action, changes in greenspace management, climate change or urban heat."

What is clear is that the city's parks, reserves and open spaces are critically important for the continued survival of most of the urban wildlife. It’s quite extraordinary to think that 47% of London is covered by green and blue space: from wild woods and formal parks, to gardens and hundreds of Sites of Importance for Nature Conservation (SINCs).

But Mr Frith says finding space to create new reserves is increasingly difficult.

"The situation is far different than it was in the 1980s; land prices are ridiculously high, and pressure to develop is the greatest it’s ever been.”

And with the the loss of connected wild areas hitting animals such as hedgehogs, bats and several bird species hard, we should not underestimate gardens as a source of biodiversity and important wildlife havens. London has an estimated 3.8 million gardens, covering 24% of the capital, but these are also undergoing worrying changes with a third of them now paved over.

What can a city, as big and diverse as London, do that’s good for both nature and the people that live and work there?

A new kind of National Park

One solution might lie with an interesting proposal for Greater London to be designated a National Park City, an idea that is rapidly gaining support in the capital. The driving force behind this innovative scheme is Daniel Raven-Ellison, a National Geographic Emerging Explorer and former Geography teacher.

And Greater London’s credentials are certainly impressive: it is 1,572 square kilometres in area, of which nearly half is green and blue (rivers and ponds) space. There are two National Nature Reserves, 142 Local Nature Reserves, 1,400 SINCs, 3.8 million gardens, 8.3 million trees and the list goes on.

Mr Raven-Ellison explains that a Greater London National Park would be a new kind of urban National Park, similar to the other 15 National Parks but not requiring legislation or having any formal planning powers. However, it would be a semi-protected area with all of the public activities and conservation efforts that take place in a traditional National Park but in an urban environment, which includes people's homes, workplaces and gardens.

He suggests that the project would be about encouraging people to welcome wildlife, examples include making it culturally acceptable to build swift bricks into new houses or having holes in fences for hedgehogs. Think of it as a set of recommended practices that could naturally connect open spaces and gardens. It’s a long-term vision that’s achieved through lots of small, individual actions: digging up concrete paving, planting flowers or not chopping down trees.

But think even bigger and large-scale projects could turn reservoirs into wetland centres and industrial complexes into Sites of Special Scientific Interest, where people can visit and volunteer if they wish to.

The massive shift for this is that it’s about recognising the value of urban wildlife

“The massive shift for this is that it’s about recognising the value of urban wildlife, and acknowledging that people live and work in cities, every one of those people is an opportunity to bring about change,” Mr Raven-Ellison says.

He says that although people currently want to protect their parks and green spaces, their importance to wildlife needs to be better understood, particularly as the city's population continues to grow. Increasing or improving habitats doesn't need to conflict with new building work though, as there are some simple changes that can be made to make the construction and design of our communities more sustainable.

Take London’s four million gardens, they are an essential component of the city’s green spaces, but a third of them are now paved over or covered in artificial grass. Mr Raven-Ellison says the potential to “re-wild" the city is huge.

“People protect what they value and what the National Park City will do is help people value wildlife and green spaces," he says.

People protect what they value and what the National Park City will do is help people value wildlife

“The acid test for our success must surely be that we have more hedgehogs, water voles and otters in our rivers, but there might be some individual losers."

Mr Raven-Ellison says that Greater London meets many requirements for becoming a National Park and is now seeking political support from London’s electoral wards and the Mayor of London for his proposal.

“Ultimately in doing that we'll be making London a phenomenally better place to live for all of us, no matter how many legs we’ve got,” he says.

The framework for a successful London National Park City could be used by other cities across the globe applying for the status.

There are already examples of urban National Parks elsewhere in the world: the US and Canada has them in, and alongside some cities; Singapore has public spaces managed by the National Parks Board; and in Scandinavia there are green corridors going through large parts of some cities. However, this would be the world’s first National Park that encompasses an entire city.

Another way

For London Wildlife Trust any National Park City proposal cannot solve all the problems that affect nature in London, but it can help to raise awareness and cultivate more sensitive approaches to the way that we design and manage the city.

“It needs to add value to the collective efforts that have been conserving and promoting London’s nature for decades, and not duplicate these efforts,” says Mr Frith.

He welcomes any proposal that raises awareness and understanding of what nature is in London and how it makes a city a beautiful place to live, work and play.

It could potentially raise our awareness of just how green London is

“It could potentially raise our awareness of just how green London is, and therefore translate into behaviours that would maintain and sustain that greenness against the pressures railing against it.”

But while he accepts that replicating existing National Park powers would confer greater protection for London's green spaces, he warns that it is unlikely to gain traction, given current government policy and priorities.

“Greater awareness might also result in quiet and relatively undisturbed places (in which wildlife flourishes) being adversely impacted. I, personally, like the fact that there are still ‘undiscovered’ tracts within our capital. So as long as we don’t kill the goose that lays the golden egg,” he says.

But is this the only solution?

While the Trust encourage any proposals for a greener London and support the emphasis on education, they, along with the other Wildlife Trusts and the Royal Society for the Protection of Birds (RSPB), are pushing for a Nature and Wellbeing Act during this parliament.

This proposed piece of legislation aims to bring about the recovery of nature within a generation, for the benefit of people and wildlife. It states that bringing back nature benefits the whole of society and therefore needs to be a priority for the government.

The partnership believes that changing a few policies is not enough to halt the loss and start the recovery; nature needs to be at the centre of how our country is run, putting wildlife habitats back into the landscape.

Greater awareness might also result in quiet and relatively undisturbed places being adversely impacted

The Act would influence how decisions are made about health, housing and other development, education, economic growth, flood resilience and every community. With the aim of connecting people with nature and the overall benefits that brings.

“If enacted as proposed it might have far more reaching impacts than a National Park City, and apply across England rather than just London,” Mr Frith says.

Find out more about the Greater London National Park City proposal and the Nature and Wellbeing Act.

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