Laura Erickson's For the Birds

Saturday, October 20, 2007

Conserve Water!

This has been a strange year in Duluth, with Lake Superior reaching its lowest level ever recorded in August, and now basements flooding from the saturated ground after weeks of LOTS of rain. But the drought in the Southeast continues unabated. Most predictions about climate change involve wildly fluctuating weather conditions and flooding in some areas and droughts in others. Atlanta is expected to run out of running water within months if there isn't significant rain there.

Water conservation is obviously critical for us humans, and as usual, what's truly good for us is also good for birds. Here's what I wrote in 101 Ways to Help Birds about water conservation:

13) Conserve water.

Water is a truly renewable resource, evaporating and returning to the air and forming clouds, then raining down on us, with the cycle repeating over and over. The amount of water on the planet remains constant. What changes is the amount of clean, drinkable freshwater for humans and wildlife.

Humans need only 1 to 2 quarts of water per day to stay alive, but we use much more. According to Cornell University’s Science News (January 20, 1997), Americans use about 100 gallons of water per person per day for drinking, cooking, washing, disposing of wastes, and other personal purposes—much higher than the world average of about 22 gallons per person per day. Not only do we use a lot of water in our homes, but agricultural and industrial water use is even more intensive. Farm policies in the United States subsidize the costs of irrigation, exacerbating the problem. As our population increases, the amount of clean water available in lakes, rivers, streams, and our uncontaminated groundwater supply is becoming depleted. Much of the groundwater that provides water used by agriculture, industry, and municipalities is being depleted far more rapidly than it’s being recharged.

How critical is water conservation for birds? Let’s consider just one situation: that of the Aransas National Wildlife Refuge, along the Gulf of Mexico on the Texas coast. People have known for a long time that the fresh water flowing into the refuge is critical for Whooping Cranes and other species that live in the estuary. Cranes, like humans living in San Antonio and other Texas cities, depend on water from the Edwards Aquifer, a source of spring water that feeds the Guadalupe and San Antonio Rivers. Of course, rainwater and runoff also provide fresh water for the rivers, but during dry spells, aquifer springs may contribute more than 80 percent of the fresh water entering the bay. When people remove this water from the aquifer for drinking, bathing, irrigation, feeding livestock, manufacturing, and other uses, the fresh water entering the estuary from the rivers declines, salinity goes up, and the ecosystem changes.

During years when not enough fresh water flows from the rivers into the estuary, marsh salinities increase and blue crab populations decline. Blue crabs are the primary food source for wintering Whooping Cranes, so a scarcity of crabs in the marshes hurts the cranes. In years when salinities are high and blue crabs are few in number, more Whooping Cranes die over the winter. “We found when salinity in the marshes reaches 23 parts per 1,000 (sea water is 35 parts per 1,000), the Whooping Cranes have to fly to fresh water to drink at least twice a day. This forces the cranes to use up more energy reserves, and increases the risk of predation whenever the birds leave the marsh,” Tom Stehn, Whooping Crane coordinator at the Aransas National Wildlife Refuge, told me. The cranes that survive have less to eat and are forced to use up fat reserves rather than putting on fat. Fat reserves are necessary for the cranes to survive their 2,400 mile migration in the spring with enough energy left over to nest successfully. Stehn notes that there is a direct correlation between Whooping Crane breeding success in summer and the population level of blue crabs they fed on the previous winter.

It’s not only Whooping Cranes that depend on fresh water inflows to the estuary. Other endangered or threatened species that live in the bay include Brown Pelicans, Reddish Egrets, and Piping Plovers. The human population of Texas is expected to double in the next 50 years. How will it be possible for us to meet our own needs and those of Whooping Cranes and other birds, especially as changing weather patterns exacerbate the degree and duration of droughts?

The heavy needs of water for the burgeoning development of central Florida have put Everglades National Park in jeopardy, the flow of the Platte River through Nebraska, where migrating Sandhill Cranes stop over every spring, is a fraction of its historical level; and much of the arid West is becoming ever more arid.

In the Southwest, the exploding human population has depleted already limited freshwater supplies, with international implications. Millions of acres of jungle-like wilderness in northern Mexico are now sterile salt flats because of heavy water use in the United States. In the days before the Hoover Dam was completed in 1936, Aldo Leopold recorded clouds of waterfowl in the Sonoran Desert’s largest wetland, the Cienega de Santa Clara. Leopold traveled the Cienega by canoe with his brother in 1922, calling it a “milk and honey wilderness.” “The river was nowhere and everywhere, for he could not decide which of a hundred green lagoons offered the most pleasant and least speedy path to the Gulf,” Leopold wrote. "So he traveled them all, and so did we.” The Cienega is but a shadow of what it once was, and is under threat of more damage from the Yuma desalting plant which, if it goes into production, will feed its toxic saline dregs directly into the Cienega.

The ever-increasing voraciousness for fresh water ensures that problems such as this become more and more prevalent, as we lose more and more of the freshwater reserves we should be protecting for our children and grandchildren as well as for birds and other wildlife.

The worst water use problems in the nation are centered in the West, where water conservation is urgent for humans as well as birds, yet flying over major cities, one can’t help but notice swimming pools sparkling in the sun. Squandering limited water supplies in arid areas increases the likelihood of wildfires and concentrates toxins that run off into rivers and ground water supplies. And even in areas of the country that have much more fresh water, such as the Great Lakes region, ground water and drinking water supplies are becoming more and more contaminated due to intensive agricultural practices and toxins from industry and people. When sewage plants carry too heavy a burden, managers sometimes hasten the treatment process by releasing blended contaminated and cleaned water together, which increases the dangers of disease for both humans and birds. One dangerous organism, Cryptosporidia, got into Milwaukee's drinking water in 1993, causing illness in about 400,000 people and killing more than 100. In the face of that, little attention was paid to the loss of birds and other wildlife.

Chemicals are so pervasive in the environment that one study found 287 different contaminants in human umbilical cord blood. These contaminants included pesticides, fire retardants, and mercury. And a June, 2005 Washington Post article reports on the alarming amount of pharmaceuticals in our nation's waterways, the result of drugs being tossed down the drain and flushed down the toilet. These chemicals, including hormones found in birth control pills, may have human health risks, since water treatment plants only remove a fraction of pharmaceutically-active compounds. Nobody is sure what the effects are, how these substances interact, or the full seriousness of their impacts on wildlife. Nonetheless, most government officials don't seem particularly interested in the issue.

When I was in graduate school, one of my friends who became a biologist for Exxon liked to say, “Dilution is the solution to pollution.” This may be true to a point, but year after year as our freshwater supplies stay constant or even dwindle, the amount of toxins we release steadily increases, making them ever more concentrated rather than diluted. On the shores of the largest, and ostensibly one of the cleanest, lakes in the world, in Duluth where I live, a series of storms in September, 1990, caused storm sewers to overflow and led to a sanitary sewage spill, washing raw sewage and even some medical wastes into Lake Superior. Birders and Duluthians found sick and dead birds all along the shore. One birder brought me three sick Sanderlings, little shorebirds that she found, weak and emaciated, along a popular beach. Parasites multiply rapidly on birds too sick to preen, and these birds were covered with lice and mites. I dusted them with a mild insecticide, but meanwhile, when I first examined the birds, a louse on the sickest bird bit me, apparently transferring to me whatever pathogens were in the bird. A couple of days later I became seriously ill, with a high fever, hallucinations, and difficulty breathing. My symptoms were similar to psittacosis (parrot fever), but blood samples proved negative for that and every other disease the blood was tested for. Meanwhile, my doctor laced me with a broad-spectrum antibiotic and I recovered. But the Sanderling died, and a Common Nighthawk I was caring for at the same time also succumbed. We Duluthians swim and boat in Lake Superior, and draw our drinking water from it, all the while leaking our wastes into the water and trusting that human beings will prove a bit sturdier than little sandpipers.

As public utilities become increasingly burdened with our growing population, and as the anti-tax movement makes it harder to maintain them, we can expect this kind of dangerous situation to happen with increasing frequency, hurting all of us. Even simple sewage backups and overflows can contaminate lakes and rivers. Conserving and using our precious water resources responsibly helps birds and humans both.

How can we make a difference? First and foremost, don’t waste water. The Environmental Protection Agency and many municipal water providers suggest on their websites a great many simple ways we can save water at home. And don’t place extra burdens on your sewer system and wastewater treatment plant. Remember, anything that goes into the sewer system is flushed with water which must be cleaned and the debris removed before it can be returned to open water. In addition, hazardous materials and medicines may not be removed and will increase water pollution. Try not to wash down drains or flush any of the following items:

  • Paper products. These do not dissolve, and add to the burden of sludge.
  • Lint and hair. These may clog your drain or the sewer system.
  • Condoms, underwear, and other non-biodegradable solids.
  • Oil, paint, and other toxins. Know where your local toxic waste disposal site is, and use it.
  • Cat litter. The sand and gravel can block a sewer line.