SHUANGLIU, CHINA — IT is still morning on the Yangtze River, but Wang Jiushan paddles his slim wooden boat from midstream, anchors it on the river bank, and sits in the bow coiling his fishing lines.
The river quietly slaps the hull as Mrs. Wang emerges from a low wicker canopy and kindles a fire in a brazier on the stern. A son and daughter, two of the couple's four children, leap onto the high bank, tumbling and laughing on a purple blanket of safflower blossoms.
Although poor, the Wangs can afford to pull in their hooks and wait out a stiff breeze in the lee of the riverbank. It is the eve of the most plentiful fishing of the year.
Spring rain soon will bring the floods that beckon carp, bream, and other fish upriver to spawn. Like countless generations of their ancestors, the Wangs will ply the river from dawn to dusk and haul in fish to the gunnels.
This will probably be one of the last abundant spring catches for the Wangs and the more than 137,000 people in fishing families on the Yangtze and its two natural reservoirs, Lakes Dongting and Poyang.
China's nominal parliament last month approved the construction of a giant dam that will greatly reduce the number of fish and imperil the Wangs' ancient way of life.
The dam threatens not only Mr. Wang's calling, but also the wild fishermen's outlook nurtured over the centuries by the rhythms and whims of the Yangtze.
Wang and other family fishermen sustain a free riverine spirit that prevailed in the far less regimented society before the Communist Party seized power in 1949.
For now, Wang and his colleagues come and go from a gathering of boats tied thwart-to-thwart. With wide sterns tapered to upswung bows, their boats resemble river fowl clustered against the breeze.
Essentially, the Three Gorges Dam will deprive Wang of a living river.
The dam will discourage spawning by curtailing spring floods and by maintaining the water at a temperature too cool for egg laying by many kinds of fish, says Chen Yiyu, director of the Institute of Hydrobiology in Wuhan.
The dam is likely to wipe out the spawning grounds all the way downriver to Dongting Lake for several fish, including bream, grass carp, black carp, big-head carp, and silver carp. The river's total spawning area will shrink by 60 percent, according to Dr. Chen.
The numbers of both Yangtze fish and subsistence fishermen have already declined 90 percent in the past three decades.
Overfishing, pollution, and construction of sluices that separate fish from their spawning grounds have caused the dramatic fall in Yangtze fisheries, says Chen.
Wang had to abandon his ancestral fishing grounds in Hanquan County on the Han River in the early 1970s after the government built sluices where the Han meets the Yangtze.
Since then, the numbers of black carp, grass carp, "huiyu," and other commercial fish have severely declined in the Yangtze, say Wang and several of his colleagues.
"Our way of life is declining because the number of fish is declining," Wang says, tugging up the sleeves of a baggy brown sweater made of homespun wool. He estimates that the number of subsistence fishermen has fallen to half the figure of five years ago.
"There will definitely be even fewer fish and fishermen after the dam is built," says Wang.
The government in the past three decades has accelerated the decline in Wang's way of life by investing far more in fixed fish farms than foot-loose family fishing boats.
Wang is trying to guide his children toward stable work on shore, but fish farming is not an option. He says he prefers vigorous Yangtze fishermen and wild fish to sedentary fish farmers and their flavorless stock.
"River fish are much tastier than those grown on farms," Wang says, reaching into the water and pulling out a wriggling, five-pound carp tethered through the gills.
"River fish swim in clean, abundant water, and they get a lot of exercise; they're fresher than farm fish, which just rot in the same stagnant water," he says, poking his waggling catch. And like their prey, fishermen benefit from a roving Yangtze life, Wang says.
"The air is fresh, and we're freer than farmers," he says. Comparatively unhampered by officials on land, Wang is raising four children, three more than officially sanctioned.
Yet fisherman Yuan Dahai says after tying up alongside Wang that life ranging on the river just satisfies a basic need.
Reciting an old addage of Yangtze fishermen, Mr. Yuan says, "Without fish, we'll go hungry; when the boat stops, we'll go hungry."
Although they face the prospect of life without fish, the fishermen view the dam with chins decidedly up.
"The construction of the dam is a big goal for the government, so our future is really just a minor problem," Wang says.