The immigrant fish found an exceptionally hospitable home in the nearly ten thousand square miles of Erie. The lake was shallow throughout its 24O-mile length, averaging less than sixty feet in depth. A flat-bottomed central basin was separated from a shallow western basin by a rocky island chain. The deepest basin, in the east, was separated from the central basin by a ridge of sand and gravel. These basins were great places for spawning, and the fish gathered by the millions. Their eggs dropped into holes in the dolomitic and limestone rock or lodged amid the gravel at the bottom, secure from egg-hunters.

Unlike Lake Superior to the north, which lay in a tough bowl of very ancient rock, Erie sat uneasily in a shifting disintegration of its shores. Instead of rock strands, it was surrounded by silty clay, and much of its shoreline was so weak it was constantly collapsing. Quick-rising western winds whipped up waves that nibbled away fifteen hundred acres of land every year. But for the lake creatures this was ideal. The collapsing shores created marshlands and shoreline havens of wild rice and aquatic plants. Great plant growths choked estuaries and bays. Fish bred there, too, and wildfowl came to mate and rest. The fish bounty of Lake Erie and its environs was a legacy of the withdrawn ice. Ohio, in particular, abounded with springs, some bubbling from the tops of hills. From these springs spread a network of deep, narrow, clear-water streams and rivers winding away toward the Ohio and the Mississippi river systems, running into the Maumee and the Sandusky, the Vermilion and the Cuyahoga, and all the other rivers linked, one way or another, with Lake Erie.

The first Europeans watched, disbelieving, as the fish hordes rushed upriver to spawn, teemed in the lake shallows, and collected by the thousands in pools and lagoons. They hunted them with spears, pitchforks, axes, nets, guns. The soldiers of a fort built on the banks of the Maumee fished each afternoon, and it was a poor day when they did not get a thousand fish. The fish collected so thickly in pools below some rapids that it was said a blindfolded man could toss a spear and get a fish nine times out of ten.

So great was the abundance of fish and fresh water that land and lake were not at first affected by the flood of settlers from the East. These eager, impatient pioneers carved fortunes from the primeval landscape. They felled an estimated twenty-five million acres of forest in fifty years. They built hundreds of dams, placing them across any river strong enough to provide water-wheel power. An 8-foot-high dam, built across the St. Marys River in 1821, backed up such a crush of migrating yellow walleyes, muskellunge, pike, bass, and suckers in the race waters flanking the

The dams destroyed the runs of the spawning fish. Some fish took to spawning in the mouths of rivers or in the lake itself. The big muskies and sturgeon, often killed with axes and hayforks when they were caught in streams too narrow for them to turn around in, found all migration to spawn blocked and remained in the lake. There, fouled in fishing gear, they were slaughtered by the thousands to protect valuable equipment. The beaches of Erie were strewn with their abandoned bodies. The sturgeon that were not fed to hogs were stacked in upright piles on the lake shores by the fishermen and set on fire. The sturgeon did not breed until they were about twenty years old, but their extremely long life—about one hundred years—enabled them to remain in the lake until recently, when all their river spawning-routes were blocked off. The muskellunge, suffering a somewhat similar fate, were apparently able to spawn in the mouths of some rivers and perpetuate some semblance of their former numbers. But in the early twentieth century, men found these great fish milling together in Maumee Bay in futile gathering for a spawning run that could never begin. Between 1902 and 1905 the men caught up to one hundred muskellunge a day until the big fish were all but wiped out.

The lake and the land around it could accept the build-up of the men and their works to a fixed point. This point was reached by the middle of the nineteenth century. In 1800 there were forty-five thousand Ohioans and an estimated thirty thousand New Yorkers, Pennsylvanians, and Canadians clustered around the lake. By 1850 the number of Ohioans had swelled to nearly two million. A flood of silt began—farmers’ topsoil leached from hillsides or from under the tramping feet of hundreds of thousands of cattle. Clay was torn from stream banks and ripped from rivers made suddenly violent in their floods by the disappearance of the great spongy network of tree roots in the fallen forests.

Sewage from hundreds of towns and villages joined the silt flow, along with effluents from tanneries, breweries, chemical works, oil wells, and mines. They were joined by blizzards of sawdust from lumber mills. Flood waters ran yellow, gray, black. The fabled Ohio springs began to dry up.

By 1875 industrious Irishmen and then Germans had drained the Black Swamp and turned it into a huge vegetable garden. While they prospered, millions of tons of rich black earth began the journey into Lake Erie from the crumbling soft banks of the farmers’ drainage ditches and from the ceaseless activity of their plows.

It now scarcely mattered that many waterpowered machines lay idle in summer, when streams diminished to a trickle. Steam power now drove the machines. Steam power sent fishermen into

However, it soon became clear that brute power and ingenuity were not quite enough to bring this man-dominated world of lake and land to order. Unaccountably, the millions of artificially propagated fish never grew to fill the fishermen’s nets. The men theorized that perhaps there was something wrong with the propagation process, but the lake itself suggested another explanation.

In 1881, when the superintendent of the Ohio fish hatcheries was collecting whitefish eggs in the western basin reefs and rocks for propagation, he saw the spawning whitefish driven away by a vast blanket of silt flushed into the lake by a cloudburst on land. The silt settled, in places covering the spawning reefs and gravel completely.

During the late nineteenth century, in every spring and fall downpour, the silt became an enveloping submarine blizzard that rolled out into Lake Erie from every river and stream. In the original balance of the lake, the spring blooming of plankton came just when trillions of fish eggs were hatching, and the young fish fed on the plankton. But the sun could not penetrate these murky waters. Great spring crops of diatoms, single-celled globular plants, once a mainstay fish food in the western basin, were obliterated. Plankton-loving ciscoes were driven east. Whitefish eggs smothered in the reef refuges. Yellow walleyes, which used to rush upriver as soon as the ice had gone, were checked and driven back into the lake without spawning.

Gradually the silt storms smothered most of the shoreline aquatic vegetation that had been a refuge for all kinds of wildlife—waterfowl, aquatic insects, amphibians, and spawning fish. The lake’s western basin held between three hundred and five hundred thousand tons of silt in suspension at almost any time. The eggs of some yellow walleyes that spawned on gravel bottoms were smothered by the silt. Others, which still sought spawning grounds up rivers, were stopped by chemicals or by sawdust that compacted in their gills, and they were driven back into the lake to wander in search of new places to spawn.

But even in the lake there was little chance to escape the rush of displaced earth into the water. The yellow walleyes had spent generations habituating themselves to dim light. They would eat only at sunrise and sunset when the light was soft enough for them to hunt. Then they

Hit by the sun, the particles of silt absorbed and retained heat, turning large areas of the lake into a kind of vast heat sponge. Some particles, decaying, actually produced heat. At the same time, heavily wooded streams lost their shade, and aquatic meadows everywhere were stripped away. The sun poured down on unshaded water everywhere. In the 1920’s an extremely hot summer drove the ciscoes into the deepest part of the central basin, and there they concentrated in immense numbers. There, also, the fishermen found them, and their eager nets caught ciscoes by the billions.

The fish and their wrecked spawning beds and the rivers of silt and chemicals were set pieces in a gradually enlarging drama. In the primeval days of the lake, about one million algae lived in every quart of water in the western basin. These tiny plants were the genesis, the starting point, for all the lake’s life systems. They had undergone delays and diversions in their life cycles during the silt blizzards, but the surface water always clarified enough to allow them to reproduce. In the 1930’s they began to proliferate in areas beyond the drifting silt.

They responded to the amount of phosphorus from fertilizers, detergents, and organic sewage flushed into the lake from men’s sewers and washed from their artificially managed fields. Within twenty-five years the algae had grown until there were almost four million of them in every quart of water. A special kind of algae, the bluegreen, came into dominance. They did not photosynthesize as much oxygen as did the others, but they demanded a greater share of the oxygen at night. The bluegreen algae reproduced at high speed, died in enormous numbers, and thus stimulated the omnipresent bacteria waiting for their deaths at the bottom of the lake. The bacteria, themselves now boosted in population, also demanded their share of the oxygen.

The blue-green algae were so well stimulated in their artificially ideal world that they displaced other plants that could not capitalize on the sewer bounty so well. Everywhere they encroached into the territories of the diatoms, suppressed their growth, and so set up a chain reaction that ended with young fish starving to death.

This was a preamble to looming catastrophe. The great submarine meadows of mayfly larvae, which in places consisted of several thousand creatures for every square yard of the lake bottom, were able to thrive through these changing conditions. They remained the great storehouse of food for all bottom-prowling fish. They could live on muddy bottoms. But gradually, oxygen became scarcer and scarcer during summers. The blue-green algae used it, the bacteria needed it; when the lake stratified into layers of different temperatures during hot, calm

In the early suffocations fish fled, and the mayflies and midges died in large numbers; but there were always enough survivors to quickly build up populations again. However, in 1953, with the winds light and the abovewater temperatures in the 8o’s, the depletion of oxygen in the western basin became complete. The loss spread over hundreds of square miles, then thousands. The lake choked, then strangled. Every living creature on the bottom that needed oxygen was killed. The midges were gone. The mayflies, those ancient successes of evolution, were wiped out.

All during the twentieth century the lake demonstrated to the men that before nature could be tamed, nature must be known. But the understanding of such things came slowly to the men. Their ignorance was a shield against the paralyzing verities of the earth. Sometimes they fluked a profit from the lake. In 1940 a group of smelt established themselves in a drainage ditch at the western end of the lake, descendants, perhaps, of sixteen million smelt eggs planted in Lake Michigan in 1912. With dazzling speed they developed in the lake and became, along with the yellow perch, the most common fish there. At least the smelt were edible—unlike the sea lamprey, which had gotten into the upper three Great Lakes and destroyed their trout and other species. The smelt made good cat food, so they might be considered successors to the long-gone ciscoes.

Meanwhile, the yellow walleye that, with the blue pike, had withstood the relentless fishing, changing temperatures, and silt and sewage, quite suddenly went into an inexplicable decline. Both the yellow walleye and the blue pike were each yielding thousands of tons of flesh to fishermen in the mid-i 950’s. Then, in ten astonishing years, they crashed. The blue pike became too scarce to be worth fishing. The yellow walleye faded to a shadow of its former abundance. This left the yellow perch, which continued to yield good crops of flesh until the 1960*8, when it, too, began to decline in number. It spawned amid vegetation, its one great weakness in a lake where rooted plants were having a tough time surviving silt, sewage, and industrial poisons.

The early silt storms had suffocated and smothered, but they did not poison. After an estimated two billion tons of silt had reached the lake from 1850 onward, the silt changed in character. Not only was it laden with phosphates and nitrates—essential chemicals in the works of man—but it also contained hundreds of other chemicals, notably DDT . This last chemical, a few men knew, influenced the hormone estrogen, which, in turn, controlled reproduction in all mammals. DDT could cause mass sterility. Buried in bottom silt, suspended in the water, the