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Decades of conservation have reunited three of Hawai'i's most endangered plants with birds coevolved to pollinate and disperse them

By Jessica Snyder Sachs, as originally appeared in National Wildlife

ON A MISTY MORNING IN SPRING 2008, federal biologist Jack Jeffrey was leading a class of middle schoolers up the eastern slope of Mauna Kea, beneath the towering koa and 'ōhi'a trees of Hakalau Forest National Wildlife Refuge on the Big Island of Hawai'i. The students had just spent two days in Hakalau's greenhouse, tending seedlings of endangered plants being readied for planting in the upper areas of the refuge's nearly 33,000 acres, which stretch from 2,500 to 6,500 feet above sea level.

The reward for their hard work was a morning birding adventure in the refuge, an ideal spot for such an outing. The U.S. government established Hakalau in 1985 specifically to protect 14 species of Hawaiian birds, most of them endangered, in one of the island's last large remnants of upland rain forest. During the next two decades, refuge staff and volunteers would expand this forest by around 5,000 acres by restoring mountaintop habitat that cattle grazing had devastated.

As was Jeffrey's habit, he led his young visitors to a cluster of small, candelabra-shaped trees, their upward-curving branches ending in sprays of strap-shaped leaves. Jeffrey liked to use this grove of flowering lobeliads as a backdrop for his talk on the 19 years of restoration efforts that followed the plant's rediscovery in the refuge in 1989.

Most North American gardeners know lobeliads as small flowering herbs commonly used in window boxes. But some 13 million years ago, one or more lobeliad relatives somehow reached the shores of Hawai'i. From these first colonists a spectacular array of 125 species evolved to include many flowering bushes and trees--none of them found anywhere else on Earth. Among their unique features, many Hawaiian lobeliads evolved long tubular blossoms and fleshy fruit designed to be pollinated and dispersed by Hawaiian birds, many of which likewise are found nowhere else.

But like much of Hawai'i's unique flora, many of its lobeliads were decimated by pigs-first introduced by Polynesians-and by cattle, sheep and goats presented by 18th-century European explorers as gifts to Hawaiian royalty. Today many native lobeliads are extinct or cling to survival in precarious perches such as cliffs, out of the reach of these voracious grazing animals.

The grove where Jeffrey took his visitors was the refuge's most mature planting of the endangered lobeliad Clermontia lindseyana. Nearby were plantings of its even rarer cousins: Clermontia pyrularia and Cyanea shipmanii. Each of these species' serendipitous rediscovery in and around Hakalau had been followed by years of hit-and-miss efforts to learn how to hand-pollinate its blossoms, germinate its seeds and find the right ecological niche for the plant to thrive, Jeffrey explained. Germination, for example, proved almost impossible for one species until a colleague had the idea of feeding the seeds to the critically endangered 'alalā, or Hawaiian crow, once an important forest-seed disperser that survives now only in captivity. The experiment worked, and the partially digested seeds produced hundreds of seedlings. Since then, refuge staff have planted these seeds across Hakalau's higher slopes to produce today's mature groves.

The hope, Jeffrey explained, was that the groves would attract Hakalau's population of 'i'iwi, a crimson honeycreeper whose long, sickle-shaped bill perfectly matches the trees' blossoms. When an 'i'iwi reaches through the tubular flower to get its nectar, the bird collects a smudge of pollen on its forehead and transfers the pollen to the next blossom it visits. By contrast, common birds such as the 'amakihi simply punch holes in the base of lobeliad flowers to steal nectar without pollinating the plants.

As Hakalau refuge supports one of the last healthy populations of 'i'iwi (around 100,000 birds), hopes were high that this ancient symbiotic relationship could be restored. But year after year, 'i'iwi ignored the plants, Jeffrey told the students. "They've forgotten their ancient nectar source." And without pollination, there was little hope for completing the second half of the plants' natural reproductive cycle: the dispersal of their seeds by the refuge's population of 'ōma'o, or Hawai'i thrush.

As a result, the aging groves of lobeliad plantings were gradually dying off instead of spreading. "So there I was, deep into my 'woe is me' speech," Jeffrey recalls, "when I see these kids start to grin. They're looking right past me, their eyes big as saucers, and I'm thinking, 'Hey, this is serious stuff I'm telling you!'"

The students' teacher pointed over Jeffrey's shoulder. "Look, Jack," she whispered. The biologist turned to see an 'i'iwi insert its long bill into a curving lobeliad blossom and then into another and yet a third before flying away.

Partners in Evolution

Hawai'i is home to around 1,000 species of flowering plants that arose during millions of years of isolation and coevolution with the islands' native animals. More than 60 percent of these plants depend on birds for pollination, seed dispersal or both. And some of the most spectacular coevolved adaptations have taken place between native lobeliads and honeycreepers such as the 'i'iwi. "If Darwin had explored Hawai'i instead of the Galápagos, he might not have needed all those years to work out his theory of evolution," says University of Hawai'i ecologist Jonathan Price, referring to the striking match between native blossoms and beaks.

Tragically, two centuries of land development and a deluge of introduced animals--from disease-carrying mosquitoes to landscape-ravaging livestock--have wrought an ecological holocaust. Though the state of Hawai'i represents just 0.2 percent of the U.S. land area, it accounts for around

75 percent of the nation's plant and bird extinctions. Currently, more than 400  Hawaiian plant and animal species are listed as threatened or endangered by the U.S. Fish and Wildlife Service--nearly all found in the wild only on this small island chain.

At least half of Hawai'i's native birds (71 species) have become extinct since the arrival of Europeans, and half of all survivors are endangered, the 'akeke'e (Kaua'i 'ākepa) and 'akikiki (Kaua'i creeper) being the most recently listed. One of the greatest threats is the rapid spread of nonnative diseases such as bird pox and avian malaria, carried by nonnative mosquitoes that breed in the mud wallows created by nonnative pigs and in the hollowed-out trunks of tree ferns, which are knocked down and eaten by the pigs.

"So many bird pollinators, including the 'i'iwi, have largely disappeared from lower elevations," says Marjorie Ziegler, executive director of the Conservation Council for Hawai'i. "Upper-elevation forests at Hakalau--currently too cool for breeding mosquitoes--are essential to the survival of native forest birds." Yet as climate change drives temperatures up, she adds, mosquitoes likewise are expanding their range into higher elevations.

Indeed, virtually all of Hawai'i's wildlife faces the triple threat of invasive species, climate change and habitat destruction, says Bruce Stein, NWF's director of climate change adaptation and a lobeliad expert. The Federation recently adopted a special resolution recognizing the biodiversity conservation challenges facing Hawai'i and urging the federal government to increase funding for species recovery and habitat protection, strengthen measures to prevent further introduction and spread of invasive species, and collaborate with the state government to address climate change in its wildlife-action plans.

For many of Hawai'i's most spectacular plants and birds, hopes of recovery hinge on re-establishing age-old ecological partnerships such as that between the 'i'iwi and native lobeliads. But some of these symbiotic relationships are known or inferred only from historical records. Recently, Price and his students at the University of Hawai'i began harnessing technology to clarify some of these ancient relationships.

"We've photographed the rarest of our flowers and scanned in images of possible pollinators," he says. The team recently made its first positive match. It involved Kokia drynariodes, a tree of which there is just a handful of individuals in the wild (on the island of Hawai'i). Though most closely related to cotton, the tree sports giant red blossoms that resemble oversized hibiscus flowers.

"We knew it must have catered to a very long-billed pollinator," Price says. And in fact, overlaying images on a computer revealed a hand-in-glove match with the kioea, a giant honeyeater and the largest of Hawai'i's bird pollinators. "It was almost magical," Price says of the overlay of bill and blossom. "Like we were seeing this interaction emerge from the mists of time." For tragically, the kioea is known only from museum specimens, having gone extinct in the mid-1800s.

The search continues for matches between surviving Hawaiian birds and the rare plants they may have forgotten. The information could be used to guide replanting efforts like those at Hakalau. At present, the 'i'iwi is looking like the lynchpin for a number of endangered flowering trees, Price says. "The dilemma is that we don't have large populations of 'i'iwi outside places like Hakalau."

Already, such grim realities have inspired some of the world's most audacious conservation measures: Field botanists such as Kenneth Wood of Hawai'i's National Tropical Botanical Garden are renowned for rappelling down vertical cliffs to use pipe cleaners to hand-pollinate endangered plants clinging to existence out of the reach of feral goats, pigs and cattle.

Completing the Cycle

At Hakalau in fall 2010, Jeffrey was leading a group of college students to his favorite patch of C. lindseyana, telling the story of how the middle schoolers had looked over his shoulder to witness the plant's historic reunion with the 'i'iwi. Soon after, 'i'iwi also rediscovered the other two endangered lobeliad species planted by refuge staff.

"I was relating how exciting it had been to see the pollination," Jeffrey recalls, "but that I was sad to be retiring soon without seeing the seed dispersed by the 'ōma'o to complete the cycle." A whirr of wings interrupted Jeffrey's lament. Looking up, he and the students saw a plump brown bird launch itself out of the bushes. Yes, an 'ōma'o.

"I'm thinking, 'Can this really be happening?'" Jeffrey recalls. He rushed into the grove that the bird had just exited and examined the lobeliad's small, round, green-yellow fruits. Several bore the 'ōma'o's distinctive triangular bill marks, exposing the bright orange seed pulp inside. "It was true!" Jeffrey says. "We had shown that 'if you plant it, they will come!'"

Three months later, Jack Jeffrey retired a happy man--or at least a hopeful one.

Jessica Snyder Sachs is a New Jersey-based writer and frequent contributor.

 

A DOSE OF DIVERSITY

Scientists are discovering that species extinctions fuel the rise and spread of infectious diseases and hinder medical research

ON A RECENT AFTERNOON, Laura Shappell followed a slender deer trail into a thicket of invasive Japanese knotweed. The plants towered over her head, and their deer-trampled stalks crunched under her boots as she vanished into the mass of pale green leaves. "If I'm not out in 10 minutes, send help," she called back.

A graduate student at Rutgers University, Shappell is a member of a research team exploring the link between biodiversity and human disease. Read more in the August issue of National Wildlife.

WILD ANIMALS may always be conservation's poster children, but without plants we would lose the very foundation of our terrestrial ecosystems. 

A rare form of black bear--that is actually white--faces threats to its survival in its British Columbia habitat

by Jessica Snyder Sachs

FROM THE DOCK of British Columbia's Hartley Bay, guide Marvin Robinson looks across the waters of the Douglass Channel to Gribbell Island. The 96-square-mile island--thickly forested in hemlock, cedar and fir--is home to the world's highest concentration of the rare "spirit bear"--a pale color variant of the American black bear. Long revered by the First Nations of British Columbia, scientists dubbed it the Kermode bear in 1905 after one of the first scientists to study the species, Francis Kermode. ... READ MORE at NATIONAL WILDLIFE.

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The editors of National Wildlife asked me to report on how wild animals are changing their diets, behaviors, and in a few cases, even their genetic makeup in their struggle to cope with global warming. It's in the December/January issue.

For this month's issue of National Wildlife magazine, I got to delve into some great environmental news. (Welcome change.) It's a feature-length roundup of newly discovered populations or rare and endangered animals--both here in North America and abroad. No random discoveries, these. Many are solid evidence that protective measures are working. 

Unbridled development and pollution threaten the Chattahoochee's ability to be all things to the millions who use and abuse the fabled river

Copyright Jessica Snyder Sachs, as originally appeared in National Wildlife magazine

GRIDLOCK seizes metro Atlanta by 8:00 am most weekdays, as traffic grinds to a halt along hundreds of miles of urban highway. Ironically, it's from this road-rage-inducing vantage point that millions have fallen under the spell of the river the Creek Indians called Chattahoochee--"the river of painted rocks." For as the waterway dips and weaves beneath dozens of the city's thoroughfares, an ethereal mist rises from its waters, broken only by the herons and kingfishers that dive from its wooded banks. Look long enough and you can imagine an ancient hunter in a dugout canoe slipping through the billowing vapor. Look again and imagine it's you, disappearing downriver, far away from the exhaust and blaring horns.

Ask anyone who lives in this sprawling metropolis of 3.5 million and you'll be hard pressed to hear a negative word about their beloved 'Hooch. They boat and fish in its waters, picnic and play on its banks, draw power from its dams and drink from its spigots. Even as the river passes through the most industrialized sections of this city, its banks remain cloaked in the river birch, sycamore and tulip poplar that inspired southern author Pat Conroy to describe Atlanta as "where they built a city and left the forest."

But despite its serene appearance, this same river also flushes metro Atlanta's toilets and silently accepts the equivalent of a major oil spill in polluted runoff each year. As a result, the 70-mile section of river south of Atlanta ranks among the five most polluted waterways in the nation. Meanwhile, the metro area's breakneck growth continues to devour the Chattahoochee's watershed--the smallest to supply a major American city--at the unprecedented rate of 50 acres a day.

Not that Atlantans stand alone in loving the Chattahoochee to death. Over the last decade, the state governments of Georgia, Alabama and Florida have remained locked in a water war over their competing rights to use the river as both water source and sewer. So great are the demands that not only water quality but water quantity--an issue more often associated with the arid West--has become a severe regional problem. So much water is being drawn from the Chattahoochee along its 540-mile journey to sea that its declining volume threatens one of the world's most productive estuaries: Apalachicola Bay in the Gulf of Mexico.

"We are at the crossroads," says Sally Bethea, director of the Upper Chattahoochee Riverkeeper, a river advocacy group founded in 1994 by Laura and Rutherford Seydel, daughter and son-in-law of Atlanta media mogul Ted Turner. "We have already changed this river forever, with 15 dams from one end to the other," adds Bethea. "But it still supports an immense diversity of wildlife. The crucial issue now is whether our leaders will insist the river be protected as a healthy ecosystem or whether we continue using it as a toilet and dump."

This workhorse of a river begins as a weeping-rock spring in the Blue Ridge Mountains, 80 miles north of Atlanta and a stone's throw from the Appalachian Trail. Surrounding the headwaters is the lush, 750,000-acre Chattahoochee National Forest, home to some 500 species of animals.

Several miles downstream, after the river tumbles out of federal land, it flows south through poultry farms and fertilized fields, picking up a heavy load of agricultural runoff. This section of the upper Chattahoochee is a magnet for construction of new, luxurious retirement communities. The development increases downstream as the river widens to form the aquatic playground of Lake Lanier, created with the completion of Buford Dam in 1956. By releasing water from the chilly bottom of its reservoir, the dam transformed the section of river below its turbines into the nation's southernmost cold-water trout stream.

Lanier itself has become the country's most-visited federal reservoir. As a result, the 38,000-acre lake is now visibly filling with tons of silt. Add to this mix the discharge of high-phosphorus wastewater from poorly regulated treatment plants and the tainted runoff from oil-slicked roads and chemically pampered lawns.

Concluding that the lake can cope with the onslaught, Georgia's Environmental Protection Division last year signaled a willingness to permit the rapidly growing counties bordering the lake to increase their wastewater discharges, contingent on enforcement of water-treatment standards. "That the state is finally setting water-quality standards for the lake is a step in the right direction," says Russ England, assistant chief of fisheries with the Georgia Department of Natural Resources. But the environmental pressures on Lanier won't abate as long as the region's unbridled growth continues, he cautions. "If they halfway try, a lot of upstream communities can learn from Atlanta's mistakes," adds England. "But their interests remain with rapid growth and against anything that would drive up the cost of that growth."

Existing regulations include a prohibition on disrupting a 25- to 50-foot buffer zone along the riverbank and requirements for erosion-control barriers on construction sites within the watershed. But enforcement is lax, claims Bethea. Part of the problem is lack of manpower. Though Georgia is the largest state east of the Mississippi River, its Environmental Protection Division staff is disproportionately small.

Between Lake Lanier and Atlanta, the Chattahoochee winds for 48 miles through the metro area's affluent suburbs. The riverfront here lies protected from further development by dozens of municipal parks and the 4,000-acre Chattahoochee River National Recreation Area, a string of 13 riverfront units. Even private homes on this stretch of the river remain largely hidden by the resilient vegetation that typifies Georgia's Piedmont region.

But just 50 feet back from the river begins a sea of impervious pavement and brick. During rainstorms, runoff that would naturally filter through vegetation-bound soil instead collects on hot surfaces and slaloms down streets to pour into the river and its tributary creeks. The unnatural wallop of sediment and heated water has already exterminated the Chattahoochee's native shellfish and now endangers temperature- and sight-sensitive fish such as trout, says naturalist Henning von Schmeling of the Chattahoochee Nature Center, a 130-acre riverfront educational facility north of Atlanta.

 

Over the next ten miles, as the river flows through Atlanta proper, it absorbs more than 250 million gallons of treated sewage and nearly a billion gallons of heated power-plant discharge a day. Even worse are the millions of gallons of raw sewage that spill into the river when rainstorms swamp the city's overburdened treatment plant.

From 1995 to 1997, the Riverkeeper spearheaded a lawsuit against the city for its sewer system's long-standing violations of the federal Clean Water Act. As a result, Atlanta was forced to pay $2.5 million in fines and comply with a strict eight-year timetable for improving water quality that included spending $360 million to upgrade its main sewage plant and committing another $25 million for watershed restoration.

A greater problem remains in polluted runoff from roads, construction sites and other nonpoint sources. The longstanding provisions of the federal Clean Water Act require the state of Georgia to reduce such pollution to a level that the river can absorb without threatening wildlife. "But the state has yet to determine the level of pollutants going into the river, let alone what it can safely handle," says biologist Andrew Schock, director of NWF's Southeastern Natural Resources Center. NWF has become particularly involved in training community activists in Atlanta's poorer neighborhoods to lobby for the restoration of the heavily polluted waters where their children fish, swim and play.

 

"Success," adds Schock, "means having the people who live in those neighborhoods involved in the decisions that affect their daily lives."

South of the city, the Chattahoochee opens up for a slow, 40-mile meander through floodplain farmland to West Point Lake on the Georgia-Alabama border. West Point's quiet waters--a stark contrast to Lanier's buzz of activity--have become a settling pond for Atlanta's tainted runoff. But even as pollution levels dampen the lake's popularity for swimming, the high load of nitrogen and phosphorous has made West Point one of the nation's most fertile bass hatcheries. Bald eagles, osprey, and heron share the world-class fishing with sports anglers, though the humans know better than to eat what they catch.

After West Point, the Chattahoochee continues south along the state border and over the fall line, where the hard rock and red clay of Piedmont Plateau give way to the soft sandstone of the coastal plain. Wildlife becomes even more abundant as the river fills its last reservoir, the shallow and reedy Lake Seminole. There, the waters of the Chattahoochee mingle with those of the Flint River before entering the Florida Panhandle under a new name: the Apalachicola. Over its final 100 miles, the meandering stream nourishes millions of acres of hardwood swamp, including the world's largest stands of tupelo trees.

The river's final act is to deliver some 16 billion gallons of fresh water a day into Apalachicola Bay, a protected estuary where fresh and salt water mix slowly to produce a world-class harvest of oysters, shrimp and fish valued at more than $100 million a year. Imperative to the health of this breeding ground is the massive influx of fresh water that keeps deep-ocean predators at bay. Declining volume and pollution have already begun to take their tolls.

"A lot of hip Atlantans love to eat Apalachicola oysters at the city's finest restaurants," comments von Schmeling. "They need to realize that the road grease from their commutes and the chemicals from their over-fertilized yards are ending up on their plates." In many ways, Atlanta's appreciation of fine Apalachicola oysters epitomizes the larger issues facing the Chattahoochee. The millions of Southeasterners who benefit from this river must now face the cost of ensuring its long-term welfare.

"The answers must come from a sense of wise stewardship," says Lindsay Thomas, the federal commissioner appointed to oversee the ongoing negotiations between the three states for the Chattahoochee-Flint-Apalachicola River Basin. But solutions have not come easily. Over the last three years, state negotiators have failed to meet four deadlines for a mutually satisfactory water-management plan. Georgia and Alabama want enough water to sustain another 50 years of booming development, without sacrificing irrigation for agriculture or river levels for commercial navigation. Florida remains desperate to stem the dwindling flow that threatens Apalachicola Bay and 90 percent of its oyster harvest.

Fighting to be heard above the fray is the 17-member TriState Conservation Coalition, which includes the Riverkeeper and two NWF affiliates, the Georgia Wildlife Federation and Florida Wildlife Federation. Lobbying for negotiators to go beyond sheer quantity, the coalition is raising complex "flow" issues that directly impact the wildlife that make southeastern rivers among the most biologically diverse on Earth. Many of the Chattahoochee's 170 species of fish, for example, rely on spring floods to reach their spawning grounds in surrounding wetlands. As withdrawals lower the river's flow, the careful timing of dam releases becomes crucial to these natural cycles. Cyclic flooding is even more pivotal to the Apalachicola Bay system, with its vast fishery nurseries.

The coalition's demands are bolstered by such federal laws as the U.S. Fish and Wildlife Coordination Act, which requires federal negotiators to consider ecological impacts; and the Clean Water Act, which mandates that waterways be kept clean enough to maintain wildlife.

Meanwhile, water-quality issues remain largely in the control of local communities, particularly metro Atlanta and its northern neighbors. Sensing the shift in mood, some of the region's developers have begun to go beyond the letter of the law to protect the Chattahoochee. "More developers are approaching us with a sincere attitude of wanting what's best for the community," says Bethea. "Other times, they're forced to work with us."

A recent case involved construction of the massive Mall of Georgia, the centerpiece of a sprawling retail complex that laid bare some 500 acres of red Georgia clay south of Lake Lanier. "The developers needed a variance to build within stream buffers and knew we could raise holy hell about it," explains Bethea. "As result we got a seat at the planning table." Specifically, the mall's developers consulted closely with Riverkeeper engineers to keep construction runoff from rolling into bordering creeks.

On the public side, Georgia Governor Roy Barnes recently budgeted 60 new positions in the state's Environmental Protection Division, primarily in programs focusing on water quality, with a promise of 140 more over five years. Barnes also vetoed a bill that would have allowed the state legislature to strike down environmental regulations set forth by the agency. Perhaps the most exciting opportunity on the horizon is the creation of a 180-mile greenway protecting riverbank from Helen to Columbus. Though it would leapfrog privately held land, the proposed Chattahoochee Riverway would become the longest river park in the nation--a project that will require $180 million to complete.

Clearly, the momentum for saving the Chattahoochee has never been greater. "What makes this river so remarkable is the fact that there are so many people who love it and depend on it," concludes England. "But the same environmental issues are being faced by great rivers across the nation." What happens here in the next few years, environmentalists agree, will largely determine whether the Chattahoochee becomes a national paradigm or a legacy lost.

Writer Jessica Snyder Sachs is the author of Good Germs, Bad Germs: Health & Survival in a Bacterial World (Hill&Wang/FSG) and Corpse: Nature, Forensics, and the Struggle to Pinpoint Time of Death (Perseus/Basic Books).

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A fragile linkage exists between the nation's water supplies, the wild places where they come from, and the life that the two support together

copyright Jessica Snyder Sachs, as first appeared in National Wildlife

FOR TENS OF MILLIONS of years, a corps of natural hydrologists ensured the continuous cleansing of our continent's water supplies. In woodlands across North America, some 200 million beavers slowed rivers and streams to a silt-dropping crawl with their semiporous dams. Moreover their relentless logging created an elaborate network of wetland meadows that absorbed and cleansed surface runoff.

Beyond the forests, tens of millions of bison and elk worked in tandem with wildfires to sustain the short-grass and tallgrass prairies that soaked up the torrential downpours of seasonal thunderstorms. Beneath these same grasslands, hundreds of thousands of prairie dogs dug vast networks of tunnels that channeled groundwater deeper, to feed and refresh underground rivers that, in turn, continually recharged the continent's lakes and above-ground streams.

In these ways, a network of keystone species helped maintain a clean supply of the continent's most vital, life-sustaining substance. For while many forms of life can survive without oxygen, none can do so without water. Indeed, 60 to 80 percent of every living cell consists of water, and all vital biological processes begin or end with this simple molecule.

So far as science can discern, life on this planet began in a watery cradle. And when astronomers scan other planets for the potential to support life, they look first for signs of the molecule H20.

As seen from space, the sparkling blue ball that is Earth reveals itself to be a paradise of wetness. Above the oceans and lakes that cover more than 70 percent of the planet's surface drifts an ever-shifting lace of water-vapor clouds. Water pours from our skies, courses down our mountains and flows across every continent, back to the seas where the warming sun sends it skyward again. In this manner, our planet continually recycles an estimated 370 quintillion gallons (18 zeros), most of it older than the oldest fossils.

As life in North America and elsewhere evolved around water's unique properties, elaborate ecosystems developed to ensure continual recycling and purification. In Water: A Natural History, environmental engineer Alice Outwater describes the consequences of disrupting these ecosystems, particularly the large-scale decimation of North America's pre-Columbian populations of beaver, bison, elk and prairie dogs. "By tampering with and in some cases eliminating the ecological niches where water cleans itself," she says, "we have simplified the pathways that water takes through the American landscape, and we have ended up with dirty water."

Without wetlands and prairie grasslands to absorb rainfall, water slaloms across the landscape, picking up and dumping sediment into streams and lakes. Without beaver dams to brake their flow, streams frequently deepen into brown-water gulleys, continually eating away at their own banks. In an even more dramatic manner, development that clears natural vegetation speeds sediment-laden runoff during rainstorms, while adding a potentially toxic load of pesticides and other chemicals. The U.S. Geological Survey's recently completed ten-year assessment of the nation's water resources found multiple pesticides and unnaturally elevated levels of phosphorus and nitrogen in virtually all streams and groundwater sampled outside undeveloped wilderness. The majority of these streams contained pesticides at levels that exceeded--and often far exceeded--federal guidelines for the protection of aquatic life. These same chemicals can likewise endanger humans if they enter the drinking water supply.

"Scientific studies have repeatedly shown that our ability to protect our water sources from pollutants--and there are many of them--relates closely to our ability to safeguard our own health, especially that of our children, with their growing bodies," observes Monty Fischer, National Wildlife Federation policy director of water resources. "As conservationists, we're also keenly aware of the crucial role an untainted and abundant water supply plays in sustaining wildlife."

Certainly, Fischer points out, part of the solution is increased water efficiency--from turning off the faucet when we brush our teeth to making sure that our municipalities repair leaky water mains and otherwise invest in efficient water-delivery systems. But more important, he says, "is a public understanding of the linkage between the water flowing out of your tap and the wild places where it comes from, both in terms of the quantity and quality of that water, and the commitment it takes to protect those water sources."

Outwater agrees, adding: "An undeniable symbiosis exists between our country's water, the land from which it springs and the life that the two support together. Safeguarding that symbiosis is a responsibility all of us must share."

New Jersey journalist Jessica Snyder Sachs wrote about the effects of pesticides on endangered species in the December/January issue.

SIDEBAR:

H₂O: The Incredible Molecule

What is it that makes H₂O the liquid of life itself?

In chemical structure, the water molecule could hardly be simpler: two hydrogen atoms stuck like Mickey Mouse ears onto a single atom of oxygen. But in that simplicity can be found water's unique properties.

In essence, every water molecule is a tiny magnet, and its strong polar nature gives it the ability to dissolve an unparalleled range of substances, including a wide range of salts. In addition to the familiar sodium-chloride molecule we know as table salt, these include scores of biologically important substances such as potassium chloride, magnesium chloride and calcium sulfate. Indeed, all living beings--from plants to humans--depend on water to release the life-sustaining minerals contained in these salts.

Water's remarkable solvent powers provide the perfect medium for virtually every biological reaction that occurs inside a living cell--from energy-storing photosynthesis to energy-consuming respiration. And water has the remarkable ability to dissolve gases--most importantly, oxygen and carbon dioxide. It is water's oxygen-carrying capacity that sustains aquatic animal life.

A water molecule's mini-magnet configuration generates a host of other queer qualities, as well. Given its simple structure and small size, it should fly apart into gaseous form at extremely low temperatures. But water molecules cluster into tight groups, with each molecule's negatively charged oxygen atom lining up with the positively charged hydrogen on its neighbors. The considerable amount of energy needed to break these "hydrogen bonds" gives water the unusually high boiling point of 212 degrees F (100 degrees C). As a result, the planet's surface water never completely evaporates under the beating sun. Instead, oceans and lakes act as impressive energy sinks for storing and slowly releasing solar energy to temper seasons, and smooth out temperature differences between day and night.

As temperatures drop toward freezing, the hydrogen bonds between water molecules perform another impressive trick. They preassemble into the open-lattice structure that gives snowflakes their beautiful patterns and makes ice lighter than water. This bizarre quality of water being lighter as a solid than as a liquid has a huge consequence: It is the reason that lakes and oceans don't freeze from the bottom up, solidifying into a global ice block that even the hottest summer would never melt.--Jessica Snyder Sachs

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