On the Trail Illegal Hunters Who Illegally Snare China's Endangered Singing Birds.

The conservationist's gaze sweeps across vast expanses of dense fields, hunting for signs of life in the pre-dawn darkness.

He speaks in less than a whisper as the team seeks a concealed position in the grasslands. Behind us, the sprawling city of Beijing slumbers on. As we wait, we hear only the quiet of the morning.

Suddenly, as the sky turns a shade lighter with the approaching day, we hear footsteps. Illegal trappers are present.

Trapped

Overhead, billions of birds, many so small that they can fit in the cup of a hand, are traveling to the south for winter.

They have taken advantage of the warmer months in Siberia, or Mongolia, feasting on insects and fruit. As the year comes to a close and icy winds bring the first frosts of winter, they journey to more temperate climates to find food and shelter.

The nation hosts more than 1,500 bird species, accounting for 13% of the global population – over eight hundred of those are migratory birds. Four of the nine major migration routes they follow converge in China.

The area of meadow where we were, on the outskirts of the Chinese capital, is an haven for small birds – farther in and the city skies offer little opportunity to rest among towering rows of concrete.

It is also an oasis for the poachers and their "barely visible nets", so thin you can hardly spot them.

The one we nearly walked into was strung across half the length of the field and supported with wooden sticks. In the middle, a meadow pipit was desperately trying to free his legs, but the more it moved, the more its feet got ensnared.

It was a protected songbird, a species under protection in China, and an important "indicator species" – meaning if its numbers are thriving, so is its environment.

Tracking the Trappers

Silva, who is in his 30s, carries out this mission for free using his personal funds. He has sacrificed many sleeping hours to set songbirds free, and he has spent the last decade persuading the police in Beijing to enforce the law.

"In the early days, no-one cared," he says.

So he gathered a team who did care and launched a group called the Bird Protection Unit. He held community gatherings and brought in the leaders of the relevant authorities. These small and persistent acts of advocacy have shown results. The police found that apprehending illegal hunters also helped in tracking down other kinds of criminal activity.

"We found our goals were partially aligned," Silva says, adding the caveat that the response is not uniform.

This fascination with birds began during childhood. He was raised in the nineties in a distinct era for the city.

He remembers exploring the fields on the city's edges where he found birds, frogs and snakes. "But starting from the 2000s, the transformation was dramatic."

China's booming economy brought millions of rural workers to cities. This expansion meant grasslands were viewed as areas for development, not sanctuaries to conserve.

This shift shocked him. The grasslands receded, as did the wildlife they housed.

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

This has not made for an easy life. A major Beijing's biggest bird dealers found out he was being investigated by Silva and retaliated.

"He gathered several of his accomplices who surrounded me and assaulted me," Silva remembers. He says he went to the police but those responsible were not held accountable.

He has also lost his army of volunteers over the years. This work demands stealth and sleepless nights. Silva says not many are willing to take on the difficult – and sometimes dangerous job.

"My life is devoted to this," he says. "I made it a project because if you want to tackle this challenge, you must devote yourself wholeheartedly. You can't do it part-time."

He says fundraising covers some of the costs – over 100,000 yuan a year – but funding has declined because of the economic situation.

So he has adopted new ways to track the poachers.

He analyzes aerial photos to find the trails worn away by the poachers. He maps those against the birds' migratory routes and looks for areas where they may rest. The aerial views can even show lines of net traps which can catch hundreds of small birds during darkness.

"Certain prized species command a high price," Silva says. "In urban centers like Beijing and Tianjin, those who want to own songbirds are now often affluent."

Although there are environmental regulations in place, Silva reckons the penalties to punish the crime do not exceed the potential profits of trapping and trading songbirds.

Keeping a caged bird was – and for some people in China, still is – a status symbol. This dates back to the Qing dynasty. Nobles and elites would build ornate bamboo cages for their birds.

It's a tradition that continues mainly among older individuals in their later years. Silva says older Chinese people don't realise they are committing a wildlife crime, or grasp that numerous birds were killed in a trap so they could buy a caged bird.

"These individuals didn't even have enough to eat growing up. Now with a little money, they have adopted the practice of caging birds," he says. "The nation progressed so fast, there was no time to raise awareness about the environment. Once adults' values are formed, they're really hard to change."

Apprehended

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

A separate individual stands outside a nearby market holding a bird cage covered by a black veil. He tells passers-by discreetly that his songbird is valuable, worth about 1900 yuan.

This offers a view of an traditional side of the city where informal vendors have established a niche trade.

The area by the river stretches for several miles and on a sunny weekday morning, there were people looking at everything from old trinkets to dentures.

Information suggested that wild songbirds could be purchased 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 traditional dance. Close by several men, all over 50, had gathered with bird cages – some had multiple in their hands. Most were covered in black fabric.

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