BARDIA NATIONAL PARK, Nepal: Chayan Kumar Chaudhary flicked through photographs captured on a hidden camera in the jungle, hoping his favorite big cat — dubbed “selfie tiger” for its love of the limelight — had made another appearance.
Thousands of camera traps have helped conservationists track Nepal’s wild tiger population, which has nearly doubled in recent years as the big cats claw their way back from the verge of extinction.
After a nine-year push to protect tigers, an exhaustive census across 2,700 kilometers (1,700 miles) of Nepal’s lowlands completed earlier this year revealed the population has grown from 121 in 2009 to an estimated 235 adult cats today.
On the frontline of the painstaking survey were trained locals like Chaudhary in western Nepal’s Bardia National Park where tiger numbers have grown nearly fivefold.
The 25-year-old helped track and record wild tiger movements through the park by scanning images taken by cameras hidden in the jungle’s undergrowth.
“It was very exciting when we checked the (memory) cards and found photos of tigers,” Chaudhary said.
“It felt like we are part of something big.”
Nepal’s southern lowlands, home to five national parks, were mapped into grids, each fitted with a pair of camera traps to record any tiger activity.
More than 3,200 of these special camera traps were installed, some by field workers on elephants to navigate the dense jungle.
“It was not an easy process and risky as well,” said Man Bahadur Khadka, head of Nepal’s department of wildlife and national parks.
These cameras were equipped with sensors that triggered a click whenever any movement or a change in temperature was detected.
Soon the photos started to trickle in: lone tigers walking past, mothers with their playful cubs and the occasional tiger feasting on a fresh kill. And Chaudhary’s favorite: a big cat that seemed to enjoy preening in front of the lens.
The census began in November 2017 and by the following March, more than 4,000 images of tigers had been collected.
“We then began analyzing the photos,” Khadka said. “Just like our fingerprints, tigers have unique stripes. No two tigers are alike.”
Conservationists say that behind Nepal’s success was a strategy to turn tiger-fearing villagers — who could earn thousands of dollars for poaching a big cat — into the animal’s protectors.
A century ago, Nepal’s lush jungles were a playground for the country’s rulers and visiting British dignitaries who came to hunt the Royal Bengal tiger.
In 1900, more than 100,000 tigers were estimated to roam the planet. But that fell to a record low of 3,200 globally in 2010.
Nepal’s tiger numbers hit rock bottom following the decade-long civil war, which ended in 2006, when poachers ran amok across the southern plains.
In 2009, the government changed tack, enlisting community groups to protect the animals. Hundreds of young volunteers were recruited to guard Nepal’s national parks, patrolling against poachers, raising awareness and protecting the natural habitat.
“Tigers are our wealth, we have to protect them,” said Sanju Pariyar, 22, who was just a teen when she joined an anti-poaching group.
“People understand that if our tiger and rhino numbers grow, tourists will come and bring opportunities. It is good for us.”
Armed with a stick, Pariyar regularly goes out on patrol to search for traps laid by poachers.
The locals have also become informants, alerting park officials if they see anything, or anyone, suspicious.
Nepal has tough punishments for poachers — up to 15 years in jail and a heavy fine — and it has recently started a genetic database of its tigers to aid investigations.
In March, police arrested a poacher who had been on the run for five years after being caught with five tiger pelts and 114 kilos of bones.
The contraband was believed to have been destined for China, a top market for wildlife smugglers, where rare animal parts are used in traditional medicine.
In 2010, Nepal and 12 other countries with tiger populations signed an agreement to double their big cat numbers by 2022. The Himalayan nation is set to be the first to achieve this target.
“If a country like Nepal — small, least developed, with lots of challenges — can do it, the others can do it,” said Nepal’s WWF representative, Ghana Gurung.
But conservationists are aware that rising tiger numbers are also good news for poachers and the lucrative black market they supply with endangered animal parts.
Tiger poaching is difficult to track because unlike with rhinos, nothing of the cat is left behind after it is killed.
“It is now more important than ever to stay vigilant,” said national park warden Ashok Bhandari.
Crouching tigers, hidden cameras: Nepal counts its big cats
Crouching tigers, hidden cameras: Nepal counts its big cats
- Thousands of camera traps have helped conservationists track Nepal’s wild tiger population
- Nepal’s tiger numbers hit rock bottom following the decade-long civil war, which ended in 2006
Nodding off is dangerous. Some animals have evolved extreme ways to sleep in precarious environments
Nodding off is dangerous. Some animals have evolved extreme ways to sleep in precarious environments
- While flying, frigatebirds can sleep with one half of the brain at a time. The other half remains semialert so that one eye is still watching for obstacles in their flight path
- Dolphins can sleep with one half of the brain at a time while swimming. Some other birds, including swifts and albatrosses, can sleep in flight
- Elephant seals sleep during the deepest portions of their dives, when they were below the depths that predators usually patrol
Every animal with a brain needs sleep — and even a few without a brain do, too. Humans sleep, birds sleep, whales sleep and even jellyfish sleep.
Sleep is universal “even though it’s actually very risky,” said Paul-Antoine Libourel, a researcher at the Neuroscience Research Center of Lyon in France.
When animals nod off, they’re most vulnerable to sneaky predators. But despite the risks, the need for sleep is so strong that no creature can skip it altogether, even when it’s highly inconvenient.
Animals that navigate extreme conditions and environments have evolved to sleep in extreme ways — for example, stealing seconds at a time during around-the-clock parenting, getting winks on the wing during long migrations and even dozing while swimming.
For a long time, scientists could only make educated guesses about when wild animals were sleeping, observing when they lay still and closed their eyes. But in recent years, tiny trackers and helmets that measure brain waves — miniaturized versions of equipment in human sleep labs — have allowed researchers to glimpse for the first time the varied and sometimes spectacular ways that wild animals snooze.
“We’re finding that sleep is really flexible in response to ecological demands,” said Niels Rattenborg, an animal sleep research specialist at the Max Planck Institute for Biological Intelligence in Germany.
Call it the emerging science of “extreme sleep.”
Chinstrap penguins and their ‘microsleeps’
Take chinstrap penguins in Antarctica that Libourel studies.
These penguins mate for life and share parenting duties — with one bird babysitting the egg or tiny gray fluffy chick to keep it warm and safe while the other swims off to fish for a family meal. Then they switch roles — keeping up this nonstop labor for weeks.
Penguin parents face a common challenge: getting enough sleep while keeping a close eye on their newborns.
They survive by taking thousands of catnaps a day — each averaging just 4 seconds long.
These short “microsleeps,” as Korea Polar Research Institute biologist Won Young Lee calls them, appear to be enough to allow penguin parents to carry out their caregiving duties for weeks within their crowded, noisy colonies.
When a clumsy neighbor passes by or predatory seabirds are near, the penguin parent blinks to alert attention and soon dozes off again, its chin nodding against its chest, like a drowsy driver.
The naps add up. Each penguin sleeps for a total of 11 hours per day, as scientists found by measuring the brain activity of 14 adults over 11 days on Antarctica’s King George Island.
To remain mostly alert, yet also sneak in sufficient winks, the penguins have evolved an enviable ability to function on extremely fractured sleep — at least during the breeding season.
Researchers can now see when either hemisphere of the brain — or both at once — are asleep.
Frigatebirds snooze half their brains in flight
Poets, sailors and birdwatchers have long wondered whether birds that fly for months at a time actually get any winks on the wing.
In some cases, the answer is yes — as scientists discovered when they attached devices that measure brain-wave activity to the heads of large seabirds nesting in the Galapagos Islands called great frigatebirds.
While flying, frigatebirds can sleep with one half of the brain at a time. The other half remains semialert so that one eye is still watching for obstacles in their flight path.
This allows the birds to soar for weeks at a time, without touching land or water, which would damage their delicate, non-water repellent feathers.
Frigatebirds can’t do tricky maneuvers — flapping, foraging or diving — with just one half of their brain. When they dive for prey, they must be fully awake. But in flight, they have evolved to sleep when gliding and circling upward on massive drafts of warm rising air that keep them aloft with minimal effort.
Back at the nest in trees or bushes, frigatebirds change up their nap routine — they are more likely to sleep with their whole brain at once and for much longer bouts. This suggests their in-flight sleeping is a specific adaptation for extended flying, Rattenborg said.
A few other animals have similar sleeping hacks. Dolphins can sleep with one half of the brain at a time while swimming. Some other birds, including swifts and albatrosses, can sleep in flight, scientists say.
Frigatebirds can fly 255 miles (410 kilometers) a day for more than 40 days, before touching land, other researchers found — a feat that wouldn’t be possible without being able to sleep on the wing.
Elephant seals slumber while diving deep
On land, life is easy for a 5,000-pound (2,268-kilogram) northern elephant seal. But at sea, sleep is dangerous — sharks and killer whales that prey on seals are lurking.
These seals go on extended foraging trips, for up to eight months, repeatedly diving to depths of several hundred feet (meters) to catch fish, squid, rays and other sea snacks.
Each deep dive may last around 30 minutes. And for around a third of that time, the seals may be asleep, as research led by Jessica Kendall-Bar of Scripps Institution of Oceanography revealed.
Kendall-Bar’s team devised a neoprene headcap similar to a swimming cap with equipment to detect motion and seal brain activity during dives, and retrieved the caps with logged data when seals returned to beaches in Northern California.
The 13 female seals studied tended to sleep during the deepest portions of their dives, when they were below the depths that predators usually patrol.
That sleep consisted of both slow-wave sleep and REM sleep. During REM, or rapid eye movement sleep, the seals were temporarily paralyzed — just like humans during this deep-sleep stage — and their dive motion changed. Instead of a controlled downward glide motion, they sometimes turned upside down and spun in what the researchers called a “sleep spiral” during REM sleep.
In the span of 24 hours, the seals at sea slept for around two hours total. (Back on the beach, they averaged around 10 hours.)
The winding evolution of sleep
Scientists are still learning about all the reasons we sleep — and just how much we really need.
It’s unlikely that any tired human can try these extreme animal sleep hacks. But learning more about how varied napping may be in the wild shows the flexibility of some species. Nature has evolved to make shut-eye possible in even the most precarious situations.
