Tracking Illegal Hunters That Illegally Capture China's Endangered Singing Birds.

The activist's eyes scan over vast expanses of dense fields, looking for any movement in the inky blackness.

He utters less than a whisper as they attempt to locate a concealed position in the grasslands. Behind us, the sprawling city of Beijing slumbers on. As we wait, the only sound is our own breath.

And then, as the sky starts to lighten with the approaching day, there is the crunch of footsteps. Illegal trappers are present.

Caught

Overhead, a multitude of winged travelers, some tiny enough that they could rest in the cup of a hand, are migrating south for winter.

They have utilized the extended daylight in northern regions, feasting on bugs and berries. As the year winds down and chilling gusts bring the first frosts of winter, they head to southern locales to breed and eat.

There are over 1500 bird species, representing roughly 13% of the planet's species – more than 800 of those are birds that migrate. Four of the nine major flyways they follow cross through China.

This particular field being monitored, on the fringes of the Chinese capital, is an haven for small birds – any further and the city skies offer little opportunity to rest among forests of concrete.

It is also an oasis for the poachers and their "fine nets", so thin you can almost miss them.

A net we almost encountered was strung across a large section of the field and propped up with bamboo poles. In the middle, a meadow pipit was desperately trying to untangle itself, but the more it struggled, the more its feet got ensnared.

This was a protected songbird, a protected bird in China, and an important "bio-indicator" – which signifies if its numbers are thriving, so is its environment.

Tracking the Trappers

Silva, who is in his 30s, does this work for free using his personal funds. He has forgone many nights of sleep to rescue birds, and he has spent the last decade urging the police in Beijing to enforce the law.

"Back in 2015, there was little interest," he states.

So he enlisted helpers who were concerned and established a group known as the Bird Protection Unit. He organized community gatherings and invited the heads of the relevant authorities. These small and persistent acts of persuasion seem to have paid off. The police found that catching poachers also helped in identifying other kinds of criminal activity.

"We found our objectives became somewhat shared," Silva says, adding the caveat that enforcement is still patchy.

His passion for avian life started in childhood. He was raised in the 1990s in a distinct era for the city.

He recalls roaming through the grasslands on the city's edges where he discovered birds, frogs and snakes. "However, beginning in the 2000s, everything changed."

Industrialization brought millions of rural workers to cities. This fast-paced development meant grasslands were considered empty places to build, not sanctuaries to conserve.

The change stunned Silva. The grasslands started disappearing, as did the wildlife they housed.

"I decided back then to work in conservation and I took this path," he says.

This has not made for an easy life. One of Beijing's biggest bird dealers discovered he was under scrutiny by Silva and retaliated.

"He assembled several of his accomplices who confronted me and beat me up," Silva recalls. He says he reported to the police but the perpetrators were not brought to justice.

He has also lost his army of volunteers over the years. This work requires patience and night vigils. Silva says not many are willing to take on the difficult – and sometimes dangerous job.

"My life is devoted to this," he says. "I treat it as a mission because if you want to tackle this challenge, you must give it your all. You can't do it part-time."

He says donations covers some of the costs – over 100,000 yuan annually – but support has waned because of the economic situation.

So he has found new ways to track the poachers.

He studies aerial photos to find the paths worn away by the poachers. He maps those against the birds' flight paths and looks for areas where they may stop for the night. The satellite images can even show netting setups which can capture hundreds of small birds during darkness.

"Siberian rubythroats and bluethroats sell for a high price," Silva says. "In big cities like Beijing and Tianjin, those who want to own songbirds are now often affluent."

Although there are wildlife laws in place, Silva argues the penalties to deter the activity do not outweigh the financial benefits of trapping and trading songbirds.

Keeping a caged bird was – and for some generations in China, still is – a status symbol. This dates back to the Qing dynasty. Wealthy individuals would build elaborate bamboo cages to display their birds.

This custom that persists mainly among retired men in their 60s or 70s. Silva says some elderly citizens don't realise they are breaking the law, or grasp that numerous birds were killed in a trap for them to purchase a caged bird.

"This generation didn't even have enough to eat growing up. Now with some disposable income, they have adopted the habit and custom of keeping birds in cages," he says. "The nation progressed so fast, there was little opportunity to educate people about the environment. Once adults' values are set, they're really hard to change."

Disrupted

Along a riverside path in Beijing, a vendor has several small cages with tiny twittering birds.

Another man stands outside a local market holding a bird cage covered by a dark cloth. He informs passers-by discreetly that his songbird is valuable, worth nearly 1900 yuan.

This offers a view of an old Beijing where informal vendors have created their own market.

The path by the river extends over several miles and on a sunny weekday morning, there were shoppers browsing everything from old trinkets to false teeth.

We were told that protected birds could be bought in a small park. The location was not concealed.

Music was blasting from a speaker under the low trees where a troop of elderly ladies were choreographing a fan dance. Close by several men, all in their later years, had congregated with bird cages – some had two or three in their hands. Most were covered in dark cloth.

But on this occasion there would be no transactions because the police had arrived. They were interviewing the bird owners and recording details. Defiant, one man claimed he was {taking his caged bird for a walk|simply exercising his