The activist's gaze sweeps over miles of dense fields, hunting for suspicious activity in the inky blackness.
He utters less than a whisper as the team seeks a place of cover in the grasslands. In the distance, the huge urban center of Beijing has yet to wake. During the vigil, the only sound is our own breath.
Suddenly, as the sky starts to lighten ahead of sunrise, there is the crunch of footsteps. The poachers are here.
Snared
Overhead, billions of birds, some tiny enough that they could rest in the cup of a hand, are migrating south 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 icy winds bring the early cold of winter, they journey to southern locales to find food and shelter.
The nation hosts more than 1,500 bird species, which is about thirteen percent of the planet's species – more than 800 of those are birds that migrate. Several of the major flyways they follow cross through China.
The area of meadow being monitored, on the edges 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 "fine nets", so delicate you can barely see them.
The trap we stumbled upon was strung across half the length of the field and held up with bamboo poles. At its center, a meadow pipit was struggling frantically to free his legs, but the more it struggled, the more its feet got ensnared.
It was a meadow pipit, a protected bird in China, and an important "bio-indicator" – which signifies if its numbers are thriving, so is its environment.
Tracking the Trappers
The conservationist, in his thirties, carries out this mission for free using his own savings. He has given up on many sleeping hours to set songbirds free, and he has spent the last decade convincing the police in Beijing to enforce the law.
"Initially, no-one cared," he states.
So he recruited volunteers who were concerned and formed a group known as the Beijing Migratory Bird Squad. He organized public meetings and brought in the leaders of the relevant authorities. These consistent and determined acts of persuasion have shown results. The police discovered that catching poachers also led to tracking down other kinds of criminal activity.
"We found our objectives became somewhat shared," Silva says, noting that implementation remains inconsistent.
His passion for avian life began during 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."
China's booming economy brought millions of rural workers to cities. This expansion meant grasslands were considered empty places to build, not sanctuaries to conserve.
The change stunned Silva. The grasslands receded, as did the habitats they supported.
"I decided back then to work in conservation and I chose this direction," he says.
This has not made for an easy life. A major Beijing's biggest bird dealers discovered he was being investigated by Silva and fought back.
"He assembled 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 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 treat it as a mission because if you want to address this major issue, you must give it your all. You cannot be half-hearted."
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 developed new ways to hunt the hunters.
He examines aerial photos to find the routes created by the poachers. He maps those against the birds' flight paths and looks for areas where they may stop for the night. The aerial views can even show lines of net traps which can catch hundreds of small birds during darkness.
"Siberian rubythroats and bluethroats sell for a premium," Silva says. "In big cities like Beijing and Tianjin, those who want to keep birds are now quite wealthy."
Although there are environmental regulations in place, Silva reckons the penalties to deter the activity do not exceed the financial benefits of catching and selling songbirds.
Owning a pet bird was – and for some generations in China, still is – a mark of prestige. This dates back to the imperial era. Nobles and elites 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 some elderly citizens may not understand they are committing a wildlife crime, or grasp that so many more birds had to die in a trap for them to purchase a pet.
"This generation didn't even have enough to eat growing up. Now with some disposable income, they have adopted the practice of keeping birds in cages," he says. "China developed so fast, there was little opportunity to raise awareness about ecology. Once people's attitudes are formed, they're really hard to change."
Apprehended
Along a riverside path in Beijing, a vendor 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 informs passers-by discreetly that his songbird is valuable, worth about 1900 yuan.
This offers a view of an old Beijing where small unofficial traders have created their own market.
The area by the river extends over several miles and on a sunny weekday morning, there were people looking at everything from vintage jewellery to dentures.
We were told that wild songbirds could be bought in a nearby green space. The location was not concealed.
Music was blasting from a speaker under the low trees where a group of elderly ladies were choreographing a fan dance. Nearby several men, all in their later years, had congregated with bird cages – some had two or three in their hands. Most were covered in black fabric.
But on this occasion there would be no sales because the police had arrived. They were interviewing the bird owners and recording details. Unyielding, one man claimed he was {taking his caged bird for a walk|simply exercising his
