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(CNN) -- Wildlife is under unprecedented threat from human activity, but research suggests that, if given space and time, even animal and plant species on the brink of extinction can recover.
A 2022 report commissioned by the nonprofit Rewilding Europe found that many European species of birds and mammals were reappearing, "highlighting the propensity of wildlife to recover and recolonise when given the opportunity".
Stack Rock Fort in Wales was once a military site and is now abandoned and reclaimed by flora and seabirds. Credit: Graham Harries/Shutterstock
Sometimes, that opportunity can be as simple as humans abandoning a place for nature to claim. Around the world, from the ruins of a temple overrun by tree roots to former war zones teeming with new ecosystems, there are striking examples of how nature proves that, once humans leave, wildlife has a chance to return.
Ta Prohm, Cambodia
Originally known as Rajavihara (Royal Temple), Ta Prohm was built in honor of the family of King Jayavarman VII. Credit: Alexander Arndt/Alamy Stock Photo
Used as a backdrop in Angelina Jolie's 2001 film "Lara Croft: Tomb Raider," this temple is located east of Angkor Thom, the former capital of the Khmer Empire.
Built in the late 12th century as a Buddhist monastery and university, more than 500,80 people lived around and tended to the temple, and 000,<> more in neighboring villages. The temple and surrounding wooded areas were abandoned three centuries later, when the king moved the empire's capital out of Angkor.
Since then, the temple has remained largely untouched, allowing trees to grow throughout the complex, most Instagrammably the gigantic fig, banana and ceibo trees whose roots wrap around the temple's walls and tower over visitors.
According to the global environmental group Wildlife Alliance, the animals thrived in the forests surrounding Angkor before overhunting and illegal trade in the last century severely depleted populations, leaving behind only a small number of common species such as muntjac deer, wild boar and Bengal cat.
In response, the Wildlife Alliance, along with Cambodian government agencies, has reintroduced a number of animals to Angkor since 2013, including crested gibbons, silver langurs, smooth-furred otters, hornbills and endangered green peacocks.
Houtouwan, Shengshan Island, China
Frozen in time, Hotouwan, on Shengshan Island, receives thousands of visitors every year. Credit: Johannes Eisele/AFP/Getty Images
It was once home to a population of more than 3,000, but its remote location, more than a five-hour drive from the mainland, made it difficult to access education, employment and food. People started leaving in the 1990s and by 2002 the village was completely abandoned.
Hotouwan, on Shengshan Island, part of the Zhoushan archipelago, once a bustling fishing village, now looks like a post-apocalyptic ghost town.
Decades of disuse have allowed nature to reclaim the land, with lush climbing plants covering all that was left behind.
Today, the village is a popular tourist destination that received more than 90,000 visitors in 2021, according to local press.
Mangapurua Valley, New Zealand
The "Bridge to Nowhere" in the Mangapurua Valley. Credit: agefotostock/Alamy Stock Photo
After World War I, land in the Mangapurua Valley in New Zealand's North Island was offered to soldiers returning from military service. Opened in 1919, the settlement once had nearly 40 soldiers and their families trying to make a living on the land.
But the remoteness of the valley and the scarcity of farmland meant that by the mid-1940s it was completely abandoned, allowing the forest to regrow and native animals to return.
Now, all that's left as proof of the settlement is the concrete "Bridge to Nowhere" that leads to nothing but wildlife. Everything else, such as houses, farms, sewers, and the Mangapurua road, has been reclaimed by the forest and is part of Whanganui National Park.
Past farming and gardening by soldiers and their families have turned much of the forest in the Mangapurua Valley into grasslands and swamps, with a few fruit trees and rose bushes reflecting a bygone era.
Whanganui National Park is home to the largest population of brown kiwis in the North Island and various bird species, including grey warblers, robins, crossbills and bellbirds. The Whanganui River is home to 18 species of fish, including eels, crayfish, and black flounder.
Yongala Steamboat, Australia
The SS Yongala is home to hundreds of different species. Credit: Blue Planet Archive/Alamy Stock Photo
After more than a century on the sea floor, Australia's largest and most intact shipwreck, the SS Yongala, has become an ecosystem, providing a habitat for some of the ocean's most magnificent wildlife.
In 1911, a year before the Titanic set sail, Cyclone Yasi sank the SS Yongala in the Great Barrier Reef marine park, causing all 122 passengers and crew to be lost at sea. It was one of the most tragic maritime disasters in Australia's history, and after an initial seven-day search that proved fruitless, the ship remained undiscovered until it was identified in 1958.
Today, the remains of the 109-meter-long wreck are covered in brightly colored corals and are home to hundreds of different species, from loggerhead turtles and marble rays to Sardinian sharks and moray eels.
Ilha da Queimada Grande, Brazil
The island of Queimada Grande, also known as the island of snakes, is home to the highly venomous golden spearhead, a type of pit-fed viper that evolved to be shorter and slender than its mainland congeners. Credit: Leo Francini/Alamy Stock Photo
Located off the coast of Sao Paulo in southeastern Brazil, it is an island surrounded by cliffs and covered in lowland rainforest and grasslands. But if it sounds like an ideal holiday destination, the local wildlife might change your mind.
Although small, Ilha da Queimada Grande is home to the world's largest concentration of golden spear snakes, estimated at around 2,000, earning it the nickname Snake Island. Apart from snakes, the island's fauna includes bats, lizards, two resident passerine birds (the wren and the banana wren), as well as numerous migratory and seabirds, such as the brown gannet, that visit the island.
Marcio Martins, a professor of ecology at the University of São Paulo, explained to CNN that the island was part of the Brazilian continental shelf, but that the drop and rise in sea level completely isolated it about 11,000 years ago. Unable to leave, the golden lancet adapted to local conditions.
At the beginning of the 1920th century, the island was inhabited by three or four lighthouse keepers and sailors, but it has been abandoned since the <>s.
Today, the island is owned by the government of Brazil and is a protected Area of Relevant Ecological Interest. To maintain its ecosystem and protect people, it is illegal to visit the island without permission.
Having visited and stayed on the island for research purposes during the 90s and 2000s, Martins describes the island as a "biological treasure."
Demilitarized Zone, Korea
The lack of human interference has allowed animals such as otters, lizards, and deer to thrive in the DMZ. Credit: Google Arts & Culture
Seventy years after the end of the Korean War, the 257-kilometer demilitarized zone (DMZ) that divides North and South Korea remains a no-man's land.
Once a center of conflict, and still strewn with ancient villages and military weaponry, the lack of human interference has allowed the land to slowly become a haven for wildlife.
- The demilitarized zone separating North and South Korea has become a haven for wildlife
The area is now a thriving home to more than 6,000 species of plants and animals. According to the National Institute of Ecology, 38% of Korea's 267 threatened species live in the DMZ. These include the Mongolian runner lizard, which lives on sandbars and under rocks, otters, which swim along the river between North and South Korea, the endangered musk deer, and Manchurian trout, which have their greatest habitat there.
Since 2019, 11 peace hiking trails, ranging from 1 to 5 kilometers, have been opened along the DMZ as a way to "give the DMZ back to the people." But despite efforts to establish peace, relations between North and South Korea have worsened in recent years.
Al Madam Village, UAE
The houses of Al Madam are now completely abandoned. Credit: Giuseppe Cacace/AFP/Getty Images
When one imagines nature taking over everything, green is probably the first color they think of. But in the village of Al Madam, nature comes in yellow.
Located 70 kilometers from the city of Dubai in the United Arab Emirates, Al Madam is a mini-ghost town that in recent years has become something of a tourist attraction.
With two rows of furnished houses and an elegant mosque, the city appears to have been hastily abandoned, leaving behind settlements that are now being reclaimed by the desert.
Although much of its history is shrouded in mystery, according to media reports the village was built in the 1970s as part of a public housing project for the Bedouins, a group of indigenous Arab tribes who historically inhabited desert regions. Before being abandoned just two decades later, the village was reportedly home to about 100 people.
There is no definitive answer as to why the village was abandoned, but researchers point to the rise of cities such as Dubai and Sharjah, where people flocked in search of better opportunities and easier living conditions.
Now, the buildings, once so beloved, are slowly disappearing under the unforgiving wilderness.
Fukushima's abandoned houses are being reclaimed by plant life. Credit: Yasuyoshi Chiba/AFP/Getty Images
The Great East Japan Earthquake and subsequent tsunami in 2011 triggered the world's second-worst nuclear catastrophe, at the Fukushima plant in northern Japan.
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In the days that followed, the Japanese government created the 20-kilometer Fukushima Exclusion Zone, and more than 150,000 residents were forced to evacuate their homes. Since then, evacuation orders have been lifted and people have been encouraged to return to some cities and towns. But some areas are still off-limits.
While you might think that nuclear disaster zones are wastelands devoid of life, research suggests otherwise. James Beasley, a professor of forestry and natural resources at the University of Georgia in the US, said in a 2016 TED talk that there was an "incredible diversity of animals" in the exclusion zone, adding that the wild boar population was so large that it had "become necessary to control their populations in parts of the exclusion zone".
Other animals that have flourished in the area include Japanese macaques, tanuki raccoons, Japanese seraus, and red foxes.
St. Kilda, Scotland
St Kilda has had inhabitants since prehistoric times, but the islands were abandoned in 1930. Credit: Allan Wright/Alamy Stock Photo
More than 60 kilometres west of the Outer Hebrides, off the northwest coast of Scotland, lies the most remote part of the British Isles. From gigantic cliffs and exceptional sea chimneys to clear waters and submerged caves, the archipelago of the St Kilda Islands is stunning natural beauty.
In 1930, following food shortages, lack of access to medical care, and declining population, the remaining 36 islanders applied to be resettled on the mainland.
Without human activity, St Kilda has become a wildlife hotspot and an ecological hotspot, home to nearly a million seabirds, including the UK's largest colony of Atlantic puffins. The islands, made up of Hirta, Boreray, Dun and Soay, are now wildlife sanctuaries, declared a UNESCO World Heritage Site.
The islands are also home to a unique type of wren and a subspecies of mouse that is twice the size of the British vole. Boreray Island and the surrounding cliffs are home to the largest gannet colony in the world, and all of the world's Soay sheep are descended from those on Soay Island.
Stack Rock Fort, Wales
Built more than 150 years ago, Fort Stack Rock is now home to seabirds and seals. Credit: Graham Harries/Shutterstock
Located off the coast of Pembrokeshire, west Wales, it's a time capsule in the shape of a long-abandoned island fort.
Built in the 1850s to protect against invasion by sea, Fort Stack Rock originally housed several cannons, troops, and officers, but its use declined over the years. During World War I it was manned by a small number of soldiers and was eventually disarmed in 1929.
Intact for almost 100 years, the fort has been slowly reclaimed by flora and fauna.
The fort's new guardian, Nicholas Mueller, director of the community interest company Anoniiem, which acquired it and plans to keep it a "living ruin," told CNN that hazelnuts grow there, and seabirds are also common, including at least three types of gulls with populations of between 300 and 500 at the fort at any given time.
According to Mueller, among the regular visitors to the fort are a pair of gray seals. Great black cormorants established a colony at the fort and can often be seen perched with outstretched wings.