Tracking Illegal Hunters Who Illegally Snare China's Protected Singing Birds.

The activist's vision darts over vast expanses of open meadows, hunting for signs of life in the pre-dawn darkness.

He utters less than a whisper as they attempt to locate a place of cover in the grasslands. In the distance, the vast metropolis of Beijing has yet to wake. As we wait, we hear only our own breath.

Suddenly, as the sky begins to brighten before dawn, we hear footsteps. The hunters have arrived.

Caught

Across the heavens, billions of birds, some tiny enough that they could rest in the cup of a hand, are traveling to the south for winter.

They have utilized the warmer months in Siberia, or Mongolia, eating insects and fruit. As the year comes to a close and icy winds bring the first frosts of winter, they journey to warmer places to find food and shelter.

The nation hosts more than 1,500 bird species, representing roughly thirteen percent of the world's total – more than 800 of those are migratory birds. Several of the major flyways they follow cross through China.

This particular field in question, on the edges of the Chinese capital, is an haven for small birds – any further and the city skies offer little opportunity to rest among towering rows of concrete.

It is equally attractive for the poachers and their "barely visible nets", so delicate you can hardly spot them.

A net we almost encountered was extending over a large section of the field and supported with wooden sticks. In the middle, a tiny bird was struggling frantically to free his legs, but the more it moved, the more its feet got ensnared.

It was a meadow pipit, a species under protection in China, and an important "indicator species" – which signifies if its population is healthy, so is its habitat.

Hunting the Hunters

The conservationist, in his thirties, carries out this mission for free using his personal funds. He has forgone many nights of sleep to set songbirds free, and he has spent the last decade persuading the police in Beijing to take this crime seriously.

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

So he recruited volunteers who did care and formed a group known as the Beijing Migratory Bird Squad. He organized community gatherings and invited the officials of the relevant authorities. These consistent and determined acts of persuasion appear to have worked. The police discovered that apprehending illegal hunters also helped in tracking down other kinds of criminal activity.

"It became clear our objectives became somewhat shared," Silva says, while pointing out that enforcement is still patchy.

Silva's love of birds began during childhood. He grew up in the nineties in a very different Beijing.

He remembers roaming through the fields on the city's edges where he encountered birds, frogs and snakes. "But starting from the 2000s, everything changed."

Industrialization brought a huge influx of rural workers to cities. This expansion meant grasslands were considered land for construction, not sanctuaries to conserve.

The transformation was alarming. The grasslands started disappearing, as did the ecosystems they sustained.

"I made the choice back then to pursue environmental protection and I took this path," he says.

It has not been an easy life. A major Beijing's biggest bird dealers discovered he was under scrutiny by Silva and retaliated.

"He assembled several of his associates who surrounded me and assaulted me," Silva recalls. He says he reported to the police but the perpetrators were not held accountable.

He has also seen the departure of his team of helpers 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.

"I do this full-time," he says. "I made it a project because if you want to tackle this challenge, you must commit completely. You cannot be half-hearted."

He says donations pays for some of the costs – over 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 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 capture scores of small birds at night.

"Siberian rubythroats and bluethroats 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 believes the penalties to punish the crime do not exceed 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 originates from the Qing dynasty. Nobles and elites would build ornate bamboo cages for their birds.

This custom that persists mainly among older individuals in their later years. Silva says some elderly citizens don't realise they are committing a wildlife crime, or understand that so many more birds had to die in a trap for them to purchase a caged bird.

"This generation didn't even have enough to eat in their youth. Now with some disposable income, they have inherited the habit and custom of keeping birds in cages," he says. "The nation progressed so fast, there was no time to raise awareness about the environment. Once people's attitudes are set, they're extremely difficult to change."

Disrupted

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

A separate individual is positioned near a nearby market holding a bird cage shrouded in a dark cloth. He informs passers-by discreetly that his songbird is valuable, worth about 1900 yuan.

This is a glimpse of an old Beijing where small unofficial traders have created their own market.

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

We were told that wild songbirds could be purchased in a nearby green space. The location was not concealed.

Loud music played from a speaker under the low trees where a troop of elderly ladies were performing a traditional dance. Close by several men, all over 50, had gathered with bird cages – some had two or three in their hands. Most were covered in dark cloth.

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