The six floods.

• Author: Durning, Alan Thein
• Position: Six great waves of resource extraction in the North American continent

In the Pacific Northwest bioregion of the North American continent, six great waves of extractive industry have brought enormous personal wealth - at the cost of ravishing ecological impoverishment. The region's history is a microcosm of the world's.

The first wave of resource extraction - the fur trade - hit the Northwest coast in 1784. For decades, China had been buying sea otter pelts from Russia - which stripped them from Siberia and the Aleutian islands. But in 1779, two ships limped into Canton from the Northwest coast, carrying a few hundred otter skins.

The ships were the remains of English mariner James Cook's last round-the-world voyage, absent the deceased Cook. The previous year, the navigator had been heading for Russian Alaska in search of the legendary Northwest Passage. During a stopover on Vancouver Island, crew members traded for otter furs from the Indians, preparing for the frozen North. These furs were still on board when Lieutenant James King went to visit the mandarins in Canton. He took twenty with him and came back with $800 in silver.

News of the price could travel no faster than the winds in those days, but other traders soon enough headed for the Northwest coast. Anchoring in Nootka Sound and other bays between Spanish California and Russian Alaska, they traded nails, blankets, and beads for the prized fur. Flotillas of canoes met the tall ships, full of Indians eager to do business.

The fur rush depressed otter populations, and prices spiraled. By the early 1800s, a good otter fur could sell for as much as $2,000 in Asia. Small wonder that the species was on the verge of extinction by 1810, after just 26 trading seasons. In that time, the human flood had energetically dispatched roughly a quarter million of the playful mammals' skins to market.

The otters' extermination likely tore a hole in the food web of the coastal waters. Recent studies show that otters eat spiny sea urchins from the ocean floor, keeping their numbers in check and preventing them from devouring the kelp forests that otters prefer. When the world economy siphoned the otters off, urchins likely proliferated. To this day, sea otters are rare on the Northwest coast, and hundreds of miles of coastline are what scuba divers call sea urchin barrens. No one knows for sure, but many ecologists suspect that in the centuries before the fur rush, an underwater jungle of kelp paralleled the coast-a mirror image of the onshore jungle of cedars, redwoods, and spruce.

As otters dwindled, the fur trade moved inland, responding around 1800 to demand for beaver fur. That is when beaver-felt hats came into fashion among the ruling classes of Europe. Once its skin won favor as headgear in London and Paris, the industrious beaver of the mainland Northwest was as doomed as its curious relative on the coast-and the major river valleys of the region were destined to be transformed by the near-eradication of these dam builders. In 1804, Meriwether Lewis and William Clark described the land they traversed as "richer in beaver . . . than any country on earth." Less than four decades later, in 1840, a traveller named Frederick Ruxton reported, "Not a hole or corner but has been ransacked."

The second wave of human industry was mining. It started small but grew into a juggernaut by the end of the 1800s. By World War I, it, too, had collapsed in all but a few places.

The geological poking and scratching began in 1852 when prospectors wandered up from the gold fields of California. There, the easily accessible gold was almost gone, and mining had turned into an industrial venture. From the tortuous ranges of southern Oregon the gold panners made their way north, chasing each other from one small strike to the next.

Up the Columbia into Canada they went, then down the Fraser to near present-day Vancouver. There, they found enough gold in 1858 to convince England that mainland British Columbia deserved Crown colony status. Next were strikes on Indian lands in Idaho, then in British Columbia's Cariboo district. This one occasioned the Northwest's first public works project - the construction of a road around the canyon of the lower Fraser River.

Prospecting peaked in the mid-1860s, then slowed despite the U.S. 1872 General Mining Act. This act granted miners rights to paydirt found on government land in exchange for a payment of $5 per acre. The mother lodes were deep underground and required big money to unearth.

Big money arrived in the 1880s. On the Coeur d'Alene River in northern Idaho, gold in 1881 turned out to be the appetizer for a feast of silver that lasted decades. Silver poured out of Milo Gulch near present-day Kellogg, and from other shafts sunk into what became known simply as Silver Valley. Other gold and silver mines opened to the north, birthing inland towns like Kimberly, Nelson, and Trail, British Columbia. For a few decades, Trail had a higher average income than almost any town in Canada.

Perched atop the Continental Divide, meanwhile, the mines of Butte were following chaotic veins of silver through the labyrinth of folds, fractures, and fissures that make up the Montana Rockies. Giant intrusions of copper mottled the lodes, annoying the miners greatly until the advent of electricity. Electric power for homes and factories needed wires to travel through, and copper was just the stuff. Butte converted itself from a second-rate silver town to the continent's greatest copper pit in the 1880s. By the turn of the century, Butte accounted for one fourth of all copper mined worldwide and had earned the nick-name "richest hill in the world."

The mining boom peaked again in the early Twentieth Century and began a long decline. In the 1980s, a new technique called heap-leaching allowed a minor resurgence: mountains of loose earth showered with a cyanide solution would yield profitable quantities of minerals. But it was nothing like the old days, and by 1993, mining employed just three-tenths of one percent of the region's workers. By then the regional economy depended more on the quality of life its natural amenities helped to make possible than on the bulky commodities it exported. And the mining past had become economic dead weight: the minerals and the money were gone, but the region was left with the holes in the ground - and the river-killing acid that drained out of them, and the acres of toxics-laced rock flour piled outside of them, and the sulphur-deadened landscapes downwind from their smelters.

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