Why wild cities are good for our health

In its final fascinating episode, Planet Earth II reveals why welcoming wildlife into our cities could be the secret to healthy urban living

As cities grow at a pace, wild animals and people are living cheek by jowl more than ever before.

The futuristic ‘Gardens by the Bay’ in central Singapore, is a revolutionary botanical garden spanning over 100 hectares of reclaimed land. It's a beautiful asset to the city, but may also offer a path to the health and happiness of its citizens.

 

"There is very strong evidence to show that maintaining a connection to nature is good for our health" explains Fredi Devas, producer of the Cities episode of Planet Earth II. "Many studies show that hospital beds with a window onto greenery result in their patients recovering faster. Schools have better attendance and companies have better staff retention, if they have vegetation close at hand."

Super trees

These 18 giant tree-like structures are beneficial to the city in many ways. Firstly their mechanical columns literally support a huge range of plant species, which are in turn habitats for wildlife. The ‘super trees’ also host solar panels to help reduce the city’s electricity bill, and the plants’ presence helps keep the city cool by providing shade, reflecting sunlight, and releasing water into the environment via evaporation.

Their attitude is to build a city within a garden

Last but by no means least, they provide a valuable space for the local residents to enjoy, something Singapore’s politicians are incredibly keen to foster.

“The Singapore government have a very good understanding of how to keep their citizens happy and healthy in the city,” explains Devas. “Their attitude is to build a city within a garden, realising that if they want the brightest people to come and work there, they need to be attracted by much more than a good salary, and green cities are a big draw.”

So Singapore has boldly prioritised this ecologically rich and sustainable space, around which it plans to build skyscrapers with wonderfully nourishing views. However it is not just Singapore that is climbing onboard this urban green revolution. Milan has recently built an award winning pair of high-rise blocks with 800 trees on their facades, which form the world's first vertical forest. "The Bosco Verticale is iconic, and people really want to live there,” Devas enthuses.

 

 

These revolutionary gardens and forests are a splendid example of how, by welcoming the countryside into our cities, we can reap huge health benefits as well as improve the wellbeing of our planet. But this concept of coexistence is not just a 21st Century phenomenon. In Ethiopia, the wall that surrounds the ancient city of Harar was built over 400 years ago to protect its people from marauding armies. Yet within this stone barricade they created special little ‘gates’ to welcome in one of the planet’s most misunderstood predators; the spotted hyena (Crocuta crocuta).

With a reputation for being sly and cunning, spotted hyenas have been known to attack livestock, and very occasionally people. Despite being the second largest predator in Africa after the lion, the Harar people believed that inviting them in would help consume evil spirits. To this day butchers leave bones out for them on the streets, and one local family even feeds them by hand.

This close relationship, built up over several centuries, has had the effect of somehow pacifying the hyenas' behaviour once within the city walls. “There seems to be a pact between the people of Harar and these particular hyenas,” explains Devas. “They simply don’t attack livestock inside the city.”

It is thought that a population of up to 200 individual hyenas have access to the city, with possibly as many as 50 strolling around the walled city at any one time. “This could be the beginning of the domestication of surely one of the world’s most unlikely animals."

Hindu feast

Tolerance of wildlife is particularly obvious in India, where they have been welcoming animals into their cities for centuries. It was in Jodphur, India, where the Planet Earth II team witnessed just how much wildlife can gain from a relationship with people. Revered by Hindus who associate them with the god Hanuman, the local Hanuman langur monkeys (Semnopithecus hector) are given as much food as they can eat.

Thanks to a life of fine dining, these urban troops are currently enjoying a baby boom, with females giving birth to their first young an astonishing four years earlier than their forest dwelling cousins. In the tough environment of the jungle, langur females are only capable of giving birth on alternate years, whereas for their privileged urban cousins, it has become an annual event.

Greening the grey

Urban wildlife ecology is such a contemporary field that researchers are only just beginning to understand how animals are faring in our concrete jungles. Globally, an area the size of Great Britain is buried under urban sprawl every ten years, so the consensus is that wildlife will have to like it or lump it.

If we create the space, the animals will come

In this most novel of habitats, wildlife must undoubtedly contend with the greatest changes to our planet, and with only a limited number of animals able to adapt, the loss of biodiversity in the face of the expansion of cities will continue to increase.

 

By greening our cities we are capable of creating a richer environment for both ourselves, and any animals invited back in. As narrator Sir David Attenborough pronounces in the final scene of this thought provoking series:

“If we create the space, the animals will come.”

UK viewers can tune in to Planet Earth II, which concludes on BBC One this Sunday at 20:00 GMT.

Be the first to know about new BBC Earth articles and wildlife programmes by signing up for the BBC's new personalised email newsletter here. You can also follow BBC Earth on Twitter and Instagram and like us on Facebook.