This Bitter Earth
Rosa Lyster on salt lakes
The extraordinary qualities of salt lakes are not always evident at first glance—almost any description of them will contain the words “overlooked” or “misunderstood.” A rainforest announces its magnificence in a photograph, and thirty seconds’ worth of footage of a coral reef should be enough to make the case for its protection. Salt lakes are not so charismatic; it’s often difficult for the casual observer to understand how crucial they are to their ecosystems. To be fully appreciated, they need context, which the geographer and writer Caroline Tracey sets out to provide in Salt Lakes: An Unnatural History.
Unlike freshwater lakes, which drain through rivers or streams, salt lakes have no outlet to the sea. Some people call them “terminal lakes,” although scientists seem to prefer the less striking, and less menacing, “endorheic lakes” (from the ancient Greek for “internal flow”). They exist mainly in the driest parts of the world, forming where water gathers at the lowest point of closed basins. Rivers flow in, but they cannot get out: the only way for water to escape is to evaporate, leaving behind the dissolved minerals that were suspended in it.
Over time—tens or hundreds of thousands of years—the salts from these minerals become more and more concentrated, although salinity levels vary widely from lake to lake. Deep Lake, in Antarctica, is so saline that the water never freezes; should you find yourself in the area, you could row across it in the middle of winter. The Dead Sea, in the Jordan Rift Valley, has a salt concentration about ten times that of ocean water, and it is capable of supporting only highly adapted microscopic life: any fish that swim in on the Jordan River die immediately. The Caspian Sea, between Europe and Asia, is only about a third as salty as the open ocean and has a number of endemic species, including a little seal with no ears.
Around the world, birds flock to salt lakes, drawn by the flies and brine shrimp that live in them, and by the relative absence of predators. (I was exhilarated to learn that brine shrimp are the same creatures that American children were always tangling with in the sitcoms I watched as a kid: sea monkeys!) The lakes in the American West are major refueling points for more than three hundred different bird species, some of them endangered, along the Pacific Flyway, the migratory route extending from Alaska to Patagonia. A 2023 survey at the Salton Sea in Southern California counted 250,000 shorebirds on a single day in August: avocets, western sandpipers, black-necked stilts. Up to 90 percent of the world’s population of eared grebes—small waterbirds with golden feathers fanning out from behind their eyes, making them look like something you’d find on a coat of arms—stops at the Great Salt Lake in Utah every spring and fall.
Many salt lakes are what I would have to call ugly: gray alkaline flats whose most distinctive feature is their hellish smell, produced by the sulfurous gas that is released as bacteria break down organic matter. Others are luminously, freakishly beautiful, in ways that seem designed to appeal to beings from other solar systems. If you were an alien, you might choose the highlighter-pink Lake Hillier in Western Australia, its water colored by a type of salt-loving algae, as the place to set down your spaceship, or you might relax at the sight of the jagged white calcium-carbonate towers spiraling out of the water of Mono Lake, near the Sierra Nevada in eastern California, reassured that you could come to no harm in a place where such strangeness has been permitted to thrive.
Mark Twain might disagree. In Roughing It (1872), he calls Mono Lake “a solemn, silent, sailless sea” in a “lifeless, treeless, hideous desert.” No stream of any kind flows out of it, and “what it does with its surplus water is a dark and bloody mystery.” The only thing that lives beneath the surface of the lake, he writes, is “a white feathery sort of worm.... If you dip up a gallon of water, you will get about fifteen thousand of these.” He goes on at jubilant length about the flies that eat the worms as they wash up on the beach.
Because the water they contain is generally undrinkable and unusable for agriculture, salt lakes have been seen as expendable, somehow beside the point. As Tracey observes, Mormon settlers in Utah came to view the Great Salt Lake with something like indignation, even disgust. What was anyone supposed to do with it? All that God-given freshwater from the rivers and the rain, channeling improvidently into the brine. Tracey cites an 1870s article in the church-owned Deseret News that called the Great Salt Lake “worthless...for uses of navigation and commerce,” “worthless for irrigation purposes,” and, finally, “worthless for any purpose.”
As Tracey works hard to demonstrate, salt lakes must be viewed in more generous terms, not least because they are drying up. For decades the rivers that once fed them have been diverted for use in irrigation, and because of climate change, the water that does get to the lakes now evaporates more quickly. The Aral Sea, between Kazakhstan and Uzbekistan, was once the largest salt lake in Central Asia and the fourth-largest in the world. But since the 1960s, as a result of the Soviet Union’s demand for cotton, its water level has decreased so rapidly that the lake has just about vanished altogether—it’s barely visible on satellite images. Its disappearance is now a kind of shorthand for ecological catastrophe.
To the west, the Caspian Sea—the world’s largest inland body of water, covering about 149,200 square miles—is also shrinking. In the United States, the Salton Sea is rapidly disappearing, and Owens Lake in eastern California is nearly gone. The Great Salt Lake has lost 70 percent of its water. Tracey points out that “far more of us than we realize are implicated” in the disappearance of these ecosystems. “If you live in Los Angeles, your drinking water comes at the expense of two salt lakes, Owens and Mono,” she writes. “If you live in San Diego, your drinking water once fed the Salton Sea.”
We underestimate the consequences of losing them. For one thing, their disappearance represents a public health crisis, already well underway in some parts of the world. The lake beds exposed by the receding water contain residue from multiple pesticides, arsenic, mercury, and other industrial and agricultural toxins. They become poisonous deserts whose dust storms can lift thousands of tons of contaminated sediment into the air.* Women in the Aral Sea region are warned against breastfeeding because of the levels of toxicity in their milk, and cancer rates are exceedingly high. Children who live around the Salton Sea have reduced lung function and “a novel form of asthma.” Scientists are worried that the air in Salt Lake City could eventually become lethal to breathe.
For another, if the lakes go, then so do the birds. The species that depend on these “freakish habitats” have nowhere else to feed, molt, and double their body weight during migration. In the Great Basin—a 220,000-square-mile area that spans six states in the American West and contains more than twenty major salt lakes, including Mono, Owens, and the Great Salt Lake—waterbird populations have declined by 70 percent since 1973. Tracey describes mass death events in which “the carcasses of eared grebes...piled up dead on the shore, looking like deflated toys” at the Great Salt Lake and the bones of so many fish accumulated on the beaches of the Salton Sea that they could be mistaken for seashells.
Perhaps most significantly, their disappearance indicates that things have gone seriously wrong. The existence of salt lakes depends on a delicate balance between inflow and outflow—because they are the end point of larger water systems, changes in the volume of a river thousands of kilometers upstream, for instance, will have a profound effect on water levels and salinity. As Tracey observes, “When the strange, hidden salt lakes start dying, it means entire ecosystems are in bad shape.” The speed at which they are shrinking is a very loud warning about unsustainable water use. Think of salt lakes as the canary in the coal mine, or the alarm that goes off when a nuclear reactor starts melting down. Keeping watch over what is happening to these places is a good way of keeping watch over everything else.
Read the full article on the Review’s website here.
Join New York Review contributor and Pulitzer Prize-winner Marilynne Robinson for a four-part seminar on the New Testament. Sessions, to be hosted on Zoom, begin May 6. Purchase tickets here.
