Following Poachers Who Illegally Snare the Nation's Endangered Songbirds.

The conservationist's eyes scan across miles of dense fields, searching for signs of life in the inky blackness.

He utters a hushed tone as they attempt to locate a place of cover in the fields. In the distance, the huge urban center of Beijing remains asleep. As we wait, we hear only our own breath.

And then, as the sky turns a shade lighter with the approaching day, there is the crunch of footsteps. Illegal trappers are present.

Trapped

In the skies above us, billions of birds, some tiny enough that they can fit in the cup of a hand, are journeying southward for winter.

They have taken advantage of the extended daylight in Siberia, or Mongolia, consuming bugs and berries. As the year comes to a close and cold breezes bring the early cold of winter, they head to warmer places to breed and eat.

The nation hosts 1500-plus bird species, representing roughly 13% of the world's total – over eight hundred of those are migratory birds. Several of the major migration routes they follow converge in China.

This particular field where we were, on the outskirts of the Chinese capital, is an haven for small birds – farther in and the city skies offer scant chance to rest among forests of concrete.

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

The one we nearly walked into was strung across a large section of the field and supported with wooden sticks. At its center, a meadow pipit was desperately trying to free his legs, but the more it struggled, the more its claws became tangled.

It was a protected songbird, a protected bird in China, and an important "indicator species" – which signifies if its population is healthy, so is its ecosystem.

Tracking the Trappers

Silva, who is in his 30s, does this work for free using his personal funds. He has given up on many nights of sleep to set songbirds free, and he has spent the last decade convincing the police in Beijing to prioritize this issue.

"Initially, authorities were indifferent," he remarks.

So he enlisted helpers who did care and formed a group called the Beijing Migratory Bird Squad. He held public meetings and brought in the officials of the local police and forestry bureau. These consistent and determined acts of advocacy appear to have worked. The police realized that apprehending illegal hunters also led to uncovering other kinds of illegal operations.

"It became clear our objectives became somewhat shared," Silva says, noting that implementation remains inconsistent.

His passion for avian life started in childhood. He grew up in the nineties in a very different Beijing.

He recalls wandering in the grasslands on the city's edges where he encountered birds, frogs and snakes. "But starting from the 2000s, the transformation was dramatic."

Rapid economic growth brought a huge influx of rural workers to cities. This rapid urbanisation meant grasslands were viewed as areas for development, not conservation areas to conserve.

The transformation was alarming. The grasslands receded, as did the wildlife they housed.

"I decided back then to dedicate myself to preservation and I took this path," he says.

This has not made for an simple journey. One of Beijing's biggest bird dealers discovered he was being investigated by Silva and retaliated.

"He gathered several of his associates who confronted me and assaulted me," Silva remembers. He says he reported to the police but the perpetrators were not brought to justice.

He has also seen the departure of his army of volunteers over the years. This work demands covert operations and lost sleep. Silva says few people are willing to take on the difficult – and sometimes dangerous job.

"This is my full-time commitment," he says. "I treat it as a mission because if you want to solve this big problem, you must devote yourself wholeheartedly. You can't do it part-time."

He says donations pays for some of the costs – more than 100,000 yuan a year – but funding has declined because of the economic situation.

So he has developed new ways to hunt the hunters.

He studies satellite imagery to find the paths worn away by the poachers. He charts these against the birds' flight paths and looks for areas where they may rest. The aerial views can even show netting setups which can catch hundreds of small birds at night.

"Certain prized species command a premium," Silva says. "In big cities like Beijing and Tianjin, those who want to own songbirds are now often affluent."

While there are environmental regulations in place, Silva argues the fines to deter the activity do not outweigh the financial benefits of catching and selling 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 ornate bamboo cages to display their birds.

It's a tradition that persists mainly among older individuals in their 60s or 70s. Silva says older Chinese people don't realise they are breaking the law, or understand that numerous birds were killed in a trap for them to purchase a pet.

"These individuals didn't even have enough to eat in their youth. Now with some disposable income, they have adopted the habit and custom of keeping birds in cages," he says. "China developed so fast, there was little opportunity to educate people about the environment. Once adults' values are formed, they're really hard to change."

Busted

On a long low wall in Beijing, a trader has several small cages with tiny twittering birds.

Another man stands outside a nearby market holding a bird cage covered by a dark cloth. He tells passers-by quietly that his songbird is valuable, worth about 1900 yuan.

This offers a view of an traditional side of the city where small unofficial traders have established a niche trade.

The path by the river stretches for several miles and on a typical day, there were shoppers browsing everything from vintage jewellery to false teeth.

Information suggested that protected birds could be bought in a nearby green space. It was easy to find.

Loud music played from a speaker under the low trees where a group of elderly ladies were performing a fan dance. Nearby several men, all in their later years, had gathered with bird cages – some had multiple in their hands. Most were concealed by dark cloth.

But on this occasion there would be no sales because the police had arrived. They were questioning the bird owners and taking names. Unyielding, one man said he was {taking his caged bird for a walk|simply exercising his