7 Animal Crossings Around the World

smontgom65/iStock via Getty Images
smontgom65/iStock via Getty Images

Animals’ natural habitats are shrinking, and the spaces they have left are often carved up by dangerous, multi-lane highways. Highways fracture ecosystems into isolated parts, which can limit genetic diversity of the organisms in each portion and jeopardize a species’ chance of survival. When animals attempt to cross these barriers, they end up putting themselves in harm’s way, and depending on their size, they can threaten the safety of people on the road.

A solution that’s gaining popularity around the world is the construction of animal crossings. Also known as animal bridges or wildlife overpasses, these structures extend over busy highways like normal bridges, but instead of cars, they provide safe passage to wildlife. Greenery planted over bridges can make them inviting places for wildlife, and fences along roads sometimes funnel animals toward the safe crossing points. Different types of bridges have been built to cater to different animals: There’s an animal crossing for crabs in Australia and one for squirrels in Washington state. Check out these and more examples of extraordinary animal crossings around the world below.

1. Wildlife Overpass // Banff National Park, Canada

Wildlife crossing in Banff National Park
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Banff National Park in Alberta, Canada, is home to megafauna like moose, elk, and grizzly bears. When these animals attempt to cross a highway, they pose a threat to human drivers and passengers as well as themselves. That’s why, beginning in 1996, officials installed six wildlife overpasses and 38 underpasses on the Trans-Canada Highway, which bears 30,000 vehicles along the 25-mile stretch from Banff National Park to the Kananaskis River every day. Wildlife mortality in the area has dropped by 80 percent as a result of the animal crossings.

2. Crab Bridge // Christmas Island National Park, Australia

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Large animals like elk and bears aren’t the only ones that deserve safe passage across busy streets. Each year, 50 million red crabs on Australia’s Christmas Island head toward the sea to spawn—a mass migration that’s been complicated by human development in recent years. To help the crustaceans reach their destination safely, the island built a 16-foot-high bridge the crabs can scale to cross a busy road. Thirty-one special crab underpasses and 65 miles of plastic barriers funneling them toward the passageways were also installed.

3. Natuurbrug Zanderij Crailoo // The Netherlands

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Natuurbrug Zanderij Crailoo

in The Netherlands is the longest wildlife crossing on Earth. The 2625-foot-long, 164-foot-wide bridge stretches across roads, railways, and a sports complex. Animals like deer, wild boar, and European badgers use it to travel to isolated environments that would otherwise be inaccessible to them. Natuurbrug Zanderij Crailoo translates to “sand quarry natural bridge,” and it's one of more than 600 "ecoducts" in the nation.

4. Nutty Narrows Bridge // Longview, Washington

Nutty Narrows squirrel bridge
Bruce Fingerhood, Flickr // CC BY-NC 2.0

Animal crossings come in all shapes and sizes. Nutty Narrows Bridge in Longview, Washington, is suspended above a busy thoroughfare and it’s just wide enough to fit a squirrel scampering to safety. Local builder Amos Peters constructed it in 1963 to keep squirrels away from the traffic below. Since then, several similar squirrel bridges have been installed around town.

5. A556 Green Bridge // United Kingdom

Overpasses that allow wildlife to avoid traffic are called “green bridges” in the UK. In 2018, one of these bridges opened above the Knutsford-Bowdon bypass on A556 in Cheshire, England. The greenery is meant to attract small animals like badgers and voles. Unlike some other wildlife crossings, this one is open to people as well. A path on the bridge aids agricultural workers crossing the highway.

6. Wildlife Overpass // Snoqualmie Pass, Washington

Animal crossing in Snoqualmie Pass
Washington State Department of Transportation, Flickr // CC BY-NC-ND 2.0

Even before the construction of a wildlife bridge near Snoqualmie Pass in Washington was completed, it was attracting animals. Deer were spotted using the overpass to cross Interstate 90 as early as 2018. After 8-foot walls were erected around the bridge to muffle noise and local flora was planted, the animal crossing official opened in 2019. It was designed to play host to elk, bears, and mountain goats, but some unexpected visitors have also been spied using the bridge. It was the site of an alleged Bigfoot sighting earlier in 2020.

7. Eco-link @ BKE // Singapore

Animals crossing in Singapore
Jnzl's Photos, Flickr // CC BY 2.0

When you hear the word Singapore, you may picture a futuristic metropolis, but the island is home to plenty of wildlife as well as people. Two rainforest nature reserves outside the city center were separated by traffic for three decades before a wildlife overpass linked them together in 2013. Singapore's Eco-Link @ BKE spans eight lanes and it was the first wildlife overpass of its kind built in Southeast Asia.

The Tiger Who Came to Tea … In the Middle of Rural Yorkshire

If you lived in Holmfirth, England, in the 1940s, there's a good chance you would've found a tiger like this one wandering around town.
If you lived in Holmfirth, England, in the 1940s, there's a good chance you would've found a tiger like this one wandering around town.
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According to the World Wildlife Fund, there are more tigers in captivity than there are in the wild. This is especially true in the United States, where backyard zoos and cub petting operations are successful—if controversial—businesses. Big cat ownership is more heavily regulated in the UK than it is in the U.S., but that wasn’t always the case. More than 70 years ago, there was at least one pet tiger living in England.

To the people of Britain, Holmfirth, 20 miles outside of Manchester, is probably best known as the picturesque setting of Last of the Summer Wine, the BBC show that ran for a staggering 37 years from 1973 to 2010 and is now appropriately credited as being the world’s longest running sitcom. But back in the early 1940s, the village was known locally as the home of Fenella the Holmfirth Tiger.

Fenella’s story actually begins more than 8000 miles away in South Africa, where she was adopted by a family of circus performers and acrobats from Yorkshire, the Overends, in the late 1930s. While touring South Africa with a traveling circus in 1939, the Overend family was offered two newborn circus tiger cubs to rear and eventually incorporate into their act. One of the cubs died barely a week later, but the other—given the name Fenella, or “Feney” for short—survived.

The Overends were forced to return to England after the outbreak of the Second World War. They took Fenella home with them to live (albeit after a brief stay in quarantine) in the back garden of their house in Holmfirth. Although she had a specially built hut and enclosure, the tiger eventually began spending just as much time in the family house as she did in the garden, and according to her owners, soon became extraordinarily tame.

The family would take her for walks through the village, including past the local primary school, where she became a firm favorite among the pupils. When the local council began to raise questions over just how tame Fenella really was, the sight of her walking calmly while being petted by all the schoolchildren as they returned from their lunch break was all it took to quash their worries.

Holmfirth viewed from the cemetery
Holmfirth in the 21st century, with nary a tiger in sight.

Tim Green, Flickr // CC BY 2.0

Fenella was sometimes permitted to run in the fields around the village, where she reportedly made friends with a local cart horse—which is surprising, given she was raised on a diet of horse meat and fish (fish and chips were one of her favorite treats). She apparently also had a fondness for climbing trees to take a nap, and supposedly had a habit of dropping down from the branches and, fairly understandably, surprising passersby. But soon the sight of a fully grown 9-foot Sumatran tigress casually idling her way through the village’s cobbled streets became the norm for the people of Holmfirth.

Fenella was intended to be a performing tiger. Similar to the cub petting operations that still exist in the U.S., visitors could pay sixpence to sit and pet her while the family was on tour. She was also worked into the family’s circus performances by staging a mock wrestling match with her owner. But though the Overends put the big cat to work, they considered her a beloved family pet rather than just another part of their act.

Sadly, Fenella died of a kidney infection during one of the family’s tours in 1950 when she was just over 10 years old. She was buried in the neighbor’s garden, which was said to be one of her favorite hunting grounds. Fenella is still remembered fondly in and around Holmfirth. In 2016, she was a highlight of the Holmfirth Arts Festival, which celebrated the cat’s life with an exhibition of photographs and archival footage of her and the Overend family. Exotic pets might not have remained as popular in the UK as they once were, but Fenella’s popularity at least remains intact.

Why Are Sloths So Slow?

Sloths have little problem holding still for nature photographers.
Sloths have little problem holding still for nature photographers.
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When it comes to physical activity, few animals have as maligned a reputation as the sloth. The six sloth species, which call Brazil and Panama home, move with no urgency, having seemingly adapted to an existence that allows for a life lived in slow motion. But what makes sloths so sedate? And what horrible, poop-related price must they pay in order to maintain life in the slow lane?

According to HowStuffWorks, the sloth’s limited movements are primarily the result of their diet. Residing mainly in the canopy vines of Central and South American forests, sloths dine out on leaves, fruits, and buds. With virtually no fat or protein, sloths conserve energy by taking a leisurely approach to life. On average, a sloth will climb or travel roughly 125 feet per day. On land, it takes them roughly one minute to move just one foot.

A sloth’s digestive system matches their locomotion. After munching leaves using their lips—they have no incisors—it can take up to a month for their meals to be fully digested. And a sloth's metabolic rate is 40 to 45 percent slower than most mammals' to help compensate for their low caloric intake. With so little fuel to burn, a sloth makes the most of it.

Deliberate movement shouldn’t be confused for weakness, however. Sloths can hang from branches for hours, showing off some impressive stamina. And because they spend most of their time high up in trees, they have no need for rapid movement to evade predators.

There is, however, one major downside to the sloth's leisurely lifestyle. Owing to their meager diet, they typically only have to poop once per week. Like going in a public bathroom, this can be a stressful event, as it means going to the ground and risking detection by predators—which puts their lives on the line. Worse, that slow bowel motility means they’re trying to push out nearly one-third of their body weight in feces at a time. It's something to consider the next time you feel envious of their chill lifestyle.

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