Once an animal unique to the West, the coyote has expanded its range to become the most widely distributed wild dog in North America. In recent years, it has moved into city parks and green belts, establishing itself as part of the urban scene.
A red fox kit, only a few weeks old, explores the world around the den in which it and its littermates were born. (As a rule, both coyotes and red foxes bear litters of six to eight, while swift foxes average only three or four.)
After wolves were removed from the scene, the coyotes muscled in, and the balance of power among canids began to shift. Coyotes are versatile predators. Depending on the circumstances, they can band together in packs to take deer and compete with wolves, or they can hunt alone to catch rodents, rabbits, and other small prey much as foxes do. So just as wolves had once impinged on coyotes, coyotes now aggressively took steps to limit the populations of their smaller competitors. Red foxes, in particular, took a major hit, and by 1900 had essentially vanished from large areas of the grasslands. As the agricultural landscape changed, from the 1930s on, red foxes pushed back in from the east and reoccupied the region.
A super-abundance of coyotes may also have been a precipitating factor in the decline of the swift fox. The smallest of the wild dogs, these guileless little creatures were once common across the short- and mixed-grass prairies, from Canada to Texas and from the Rockies to the Dakotas. By the 1940s, however, the species had been extirpated from the northern plains, probably as a result of coyote predation, together with loss of prey (notably rodents), loss of habitat to the plow, and loss of life to poison baits intended for other predators. Thanks to decades of effort by conservationists, small populations of swift foxes have recently been reestablished on the Blackfeet Reservation in Montana, in southern Alberta and Saskatchewan, and in South Dakota. In Canada alone, the population has risen from zero to around 650 since 1983, when the first captive-bred animals were released. These days, the greatest impediment to the survival of swift foxes appears not to be direct predation by coyotes (though, of course, that still occurs) so much as competition with their canny red cousin. When red foxes are present, swift foxes make themselves scarce, though exactly why this happens, no one can say for sure.
Swift fox
One thing we can be sure of, however, is that Wile E. Coyote still reigns supreme as top dog across the prairies. After a century or more on agriculture’s Most Wanted list as livestock predators, coyotes are still out there everywhere you look, howling, breeding, birthing, going about their business. By any sensible measure, attempts to limit their numbers have been a complete flop, much like trying to empty the bathtub without turning the water off. To have any lasting effect, a coyote-control program must target at least 75 percent of the breeding animals in a given neighborhood, a goal that is seldom achievable in practice. Yet without such drastic reductions, “control” becomes merely a means of thinning the population and ensuring that the survivors have adequate food to put them in prime condition to reproduce. When food is abundant, mature females produce large litters, and even subadults under the age of two are likely to reproduce and make a contribution to the baby boom.
But if coyote “control” can’t be relied upon to achieve its intended results, it inevitably triggers a cascade of subtle, unseen, and unanticipated changes. For example, a reduction in the numbers of coyotes (however temporarily) provides an opening not only for red foxes but also for skunks, bobcats, and other middle-sized predators, many of which prey heavily on duck nests. Fewer coyotes thus translates indirectly into fewer ducks and a chain of unknown effects on wetlands.
Meanwhile, on the grassy uplands, the removal of coyotes can also cause unexpected shifts in the abundance of rodents. For instance, one study in Texas found that when coyotes were present in good numbers, the prairie was home to flourishing populations of a dozen species of microherbivores, including deer mice, pocket mice, harvest mice, and Ord’s kangaroo rat. But after half of the coyotes had been shot, the mouse populations crashed and the only species that remained was the kangaroo rat. (Presumably, predation by coyotes normally kept kangaroo rats in check and allowed the other, less competitive species to claim living space.) Since kangaroo rats are aggressive foragers that can push grasslands over the brink and encourage the invasion of desert shrubs, their dominance may have made the rangelands less hospitable for cattle. Meanwhile, with the coyotes held in abeyance, black-tailed jackrabbits multiplied to such an extent that they consumed any cattle fodder that was left. Thus, far from being dispensable animals (as one range manager described them in 1973), coyotes are a keystone species in rangeland ecology and the unlikely guardians of the cattle industry.
Long honored as the Trickster, Coyote still walks the prairie with us, calling us to look beyond the obvious.
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> STRANGE COMPANIONS
Coyotes and American badgers are middle-sized carnivores that share a taste for ground squirrels, prairie dogs, and other middle-sized prey. One might expect, then, that prey taken by one species would be a loss to the other. The fact that badger populations increase when coyotes are removed suggests that this kind of competition actually does occur and that badgers are typically the losers.
Under certain circumstances, however, the rules of engagement appear to shift from winner versus loser to win-win. If the two species find themselves working the same rodent colonies, and if such prey is scarce, the hunters may form an unlikely alliance. As the badger pursues its prey by burrowing underground, a coyote stands guard up top, ready to pounce on any rodent that makes a run for it. Meanwhile, down below, panic ensues, and the hardworking badger takes advantage of the confusion to make its kill.
Although hunting partners never share food with each other, they sometimes take time out to play— even to wrestle like pups—or simply to touch noses or lie down with each other. One observer described an encounter in which a coyote laid its head on the badger’s neck, licked its face, jumped in the air, and made “other expressions of unmistakable joy.” No wonder the two predators are often described in Native stories as neighbors and friends and are even said to address each other as cousins.
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WATER OF LIFE
Here is a land where life is written in water.
THOMAS HORNSBY FERRIL, COLORADO, 1940
IT WAS LITTLE more than a puddle at the side of the road, the kind that appears in spring and is gone by midsummer. Two days earlier, it had lain frozen, burdened by a freak spring storm. But in the sudden warmth of late April, the tide of the seasons had turned and the hollow was filled with sunlight and the bright creaking of frogs.
The far bank bristled with willows and wild roses and, poking up out of their midst, a single, stunted aspen that carried two large masses of twigs. One was flat topped, like a crow’s nest, and did not appear to be in use, but the other was massive and messy and comically overbuilt for the meager tree that supported it. It had to be a hawk’s nest. And, yes, there was a bird on this one, a large, dark form with a knob of a head that popped up above the rim. Do you suppose that it’s a Swainson’s hawk—the kind with the rich chestnut-brown bib—or its rarer cousin, the pale-fronted ferruginous hawk? Out come the field guides and binoculars. But wait: the shape that is sprawled on the hawk’s nest doesn’t look like a raptor at all. It’s some kind of gray-backed bird with a sinuous black neck, a bar of white on its cheek and a stubby, ducklike bill that extends languidly over the rim of the nest. Could it be—what else could it be? A Canada goose!
I can’t tell you if that goose had merely settled on the nest to sunbathe or if it had inexplicably taken a notion to lay and incubate its clutch at the top of a scrubby aspen. Strange as it may seem, this turns out to be a credible possibility. Although Canada geese usually nest on the ground near water or, at most, on slightly elevated surfaces such as grassy hummocks and beaver lodges, they actually take over abandoned hawk nests as much as 6 yards, or meters, above ground. Wh
en the goslings are ready to leave, they step off the nest platform and flutter their tiny wings toward what will hopefully be a soft landing. Be that as it may, there is one thing I do know for sure. Even the most unprepossessing prairie puddle is a site of wonderment, a place where the unexpected happens daily and where nothing can safely be taken for granted.
It isn’t just the life of watery places that is so interesting. Water itself is amazing. For instance, the droplets that collect in a roadside ditch, or that rain down on our heads, may have been in existence for billions of years, perhaps since the earliest beginnings of the universe. Originally derived from the cloud of roiling, boiling gases that gave rise to the sun and stars, water is a fusion of hydrogen and oxygen into a compound, H2O, that still participates in the restless energy of creation. It is constantly in a process of transformation. That raindrop on your nose was, until recently, a cloud. And before that, those same molecules of water may have gone through countless passages from snowfall to spring runoff, groundwater to marsh, marsh to river, river to ocean, ocean to wind, wind to cloud, in an endless, cyclic journey through the physical world.
And that is still not the whole picture. For not only is water capable of shifting from solid to liquid to gas—making it the only substance to exist in all three states under normal conditions on Earth—it also routinely makes the unfathomable leap from nonliving to living. The miracle of life derives from a thin, protoplasmic soup that, depending on the function of the cell, consists of between 50 and 90 percent water. (Our own tissues average out at about 50 percent.) So that same raindrop, which by now is dribbling off your chin, has likely also made a journey through the living world. From rain to soil, root to leaf, leaf to goose, goose droppings to soil, soil back to air, it has flowed through the food web, moving freely from organism to organism. Has it experienced life as an amoeba? An earthworm? A brontosaurus in a swamp? In the shape-shifting world of water, stranger things have happened.
Even in midwinter, a film of algae brings color and life to this pond in the Black Kettle National Grassland, near Cheyenne, Oklahoma.
Water is the medium of life, so it is not surprising that aquatic habitats— including oceans, rivers, lakes, ponds, and marshes—are among the richest and most productive environments on Earth. But it may be surprising to discover that this generalization holds true for the landlocked Great Plains, a region that we typically associate with drought, dust storms, and water shortage. On a planet where two-thirds of the surface is covered by water, the wide expanse of the prairies is a sea of dry land, broken here and there by small islands of aquatic habitat. Broadly speaking, the area covered by water is greatest in the eastern, tall-grass country and diminishes toward the west, following the logic of declining precipitation. Thus, in parts of central Manitoba, the inrush of moisture-bearing air from both west and south produces lush meadows and extensive, reedy marshes that occupy as much as 25 percent of the landscape. But on the prairies of Alberta, where the mountains block out the rain, wet meadows and marshes cover a mere 5 percent of the range. Similarly, if you cross the border into the States and head for the southern plains, the area of surface water declines incrementally. In Nebraska and Texas, for example, where the summer sun has the power to suck whole rivers out of their beds, the coverage of water declines to a fraction of a percent. Yet, though limited in physical area, the aquatic habitats of the prairies are biologically immense, capable under ideal conditions of producing more life in less space than almost any other environment on the planet.
The rising trill of the red-winged blackbird is as bright, in its own way, as the epaulettes on the wings of breeding males. Redwings are found in wetlands across the Great Plains, where they build and defend nests in dense stands of cattails.
Arthur Savage photo
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> TURTLE ISLAND
There was a world before this world, the Lakota storytellers say, but the Creating Power was not pleased with it. He said to himself, “I will make a new world.” So he took his sacred pipe and his pipe bag, and he sang four songs. When he sang the first song, it started to rain. When he sang the second and third songs, it poured, and the rain-swollen rivers overflowed their beds. When he sang the fourth song and stamped on the earth, it split open in many places like a shattered gourd, and water flowed from the cracks until it covered everything.
By the time the rain stopped, all the people and animals had drowned. The Creating Power thought: “It’s time to unwrap the pipe and open the pipe bag.” The wrapping and the bag contained all manner of animals and birds, from which he selected four animals known for their ability to stay under water for a long time.
First he sang a song and took the loon out of the bag. He commanded the loon to dive and bring up a lump of mud. The loon did dive, but it brought up nothing because the water was too deep. The otter and the beaver tried in their turn, but they too brought up nothing.
At last the Creating Power sang the fourth song and took the turtle out of the bag. “You must bring the mud,” the Creating Power said. The turtle dived into the water and stayed below so long that the other three animals were certain it was dead. But when it finally surfaced, its feet and claws—even the space between its upper and lower shells—were filled with mud.
Scooping mud from the turtle’s feet and sides, the Creating Power began to sing. He sang as he shaped the mud in his hands and spread it on the water to make a spot of dry land. Eventually, he made so much land that the water was replaced by earth. “Water without earth is not good,” thought the Creating Power, “but land without water is not good either.” Filled with pity, he wept for the earth, and his tears became oceans, streams, and lakes. “That’s better,” he thought . . .
He named this new world Turtle Island because it was made from the mud that the turtle had brought from under the water. (This is an abbreviated version of the story as it was told in the early 1900s.)
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Putting Marshes on the Map
For the purposes of discussion, it is useful to divide the aquatic habitats of the Great Plains into two categories: wetlands, or marshes, and rivers and lakes. Scientifically speaking, the term “wetland” refers to any shallow depression—less than 6 feet (2 meters) deep—that is capable of holding water for long enough to permit the growth of sedges, cattails, and other nonwoody, semiaquatic vegetation. In other words, it is basically a puddle filled with water-loving plants. Yet this deceptively simple definition leaves room for almost infinite variability in water depth, temperature, permanence, chemistry, soil type, fertility, life history, and just plain chance, so every prairie wetland is, to some extent, a unique habitat that supports a unique community of organisms.
Mayflies, genus Ephemera, spend most of their lives in the water, first as eggs, then as herbivorous larvae that scuttle and scurry along the bottoms of streams. The airborne adult form survives for no more than a day or two, just long enough to reproduce.
Millions of these mostly small, self-contained marshes are dotted across the Great Plains, providing resource-rich refuges for a remarkable diversity and number of insects, reptiles, amphibians, mammals, and—most spectacularly—birds. For example, the Llano Estacado, or High Plains region, south of Amarillo, Texas, is so emphatically dry and flat that it cannot sustain the flow of a permanent river. Once described as the “great Zahara of North America,” the region is now essentially a wall-to-wall expanse of cotton fields under irrigation. Yet this dreary prospect is redeemed by the presence of around 20,000 shallow, saucer-shaped depressions known as playas, or playa lakes, that serve as havens for wildlife. (An additional roughly 6,000 playas occur farther north in the Texas Panhandle, as well as in adjacent parts of New Mexico, Colorado, Kansas, and Oklahoma.) Scoured out by some still-mysterious interaction between wind, water, and underlying geology, these clay-lined basins have been in existence for at least ten thousand years and, judging from remains found buried in their beds, once served as watering holes for both Columbian mammot
hs and the Folsom-era humans who hunted them. Somewhat more recently, in 1541, when Francisco Vásquez de Coronado marched across these plains, he was as impressed by the playas—“round like plates, a stone’s throw wide”—as he was by the bison that he encountered near them.
Throughout their long history, playas have presumably functioned in the same way as they do today: as catch basins for runoff and rain. As a rule, they fill up during spring cloudbursts, reach peak levels in June, and thereafter (through evaporation and slow seepage) gradually disappear. The deeper the depression and the more water it holds, the longer the playa persists through the season. Since most playas are flat bottomed and less than a yard in depth, they are generally dried out by December, at the latest. Only the deepest basins— including the increasingly large number that have been modified to retain water for irrigation—hold moisture year round and during periods of drought. Yet despite their ephemeral nature, playas sustain an abundance of life, including not only semiaquatic plants such as barnyard grass, curly dock, and pink smartweed but also a mix-and-match selection (differing from pond to pond) of up to six species of waterboatmen; five types of dragonflies; fifteen kinds of small marsh flies, or midges; nineteen kinds of freshwater shrimp; and dozens of other squirming, swimming, and flying invertebrates. This living soup, in turn, sustains populations of larger organisms, including amphibians (up to fourteen species of salamanders, frogs, and toads), reptiles (especially yellow mud turtles), and mammals (deer mice, cottontails, badgers, striped skunks, coyotes, and raccoons, among others).
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