Endangered Species Handbook

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Aquatic Ecosystems

Preserving Aquatic Ecosystems

     Only recently have some aquatic environments received protection in some parts of the world.  New marine sanctuaries that protect coral reefs and other sea life have been set aside in a growing number of countries.  In 1994, Australia, the United States and six other nations founded the International Coral Reef Initiative to encourage preservation of reefs endangered by pollution, overfishing and other causes.  In the future, sanctuaries and international agreements will provide major means of conserving these ecosystems.  Unfortunately, many of these sanctuaries allow commercial fishing and the collection of mollusks.  The value of aquatic ecosystems in preserving biodiversity is only beginning to be appreciated, aided by the growing popularity of bird-watching, scuba diving and coral reef tourist visits that are educating many people about the importance of protecting these fragile ecosystems.
     Private organizations and universities are playing important roles in monitoring and conserving delicate aquatic habitats.  The International Marine life Alliance, based in the Philippines, is convincing fishermen to catch fish in hand nets, rather than poison or dynamite reefs.  The Global Coral Reef Alliance is investigating diseases that are afflicting reefs through scientific research, and Greenpeace International has been active in conducting worldwide surveys of the deterioration of coral reefs.  Depletion of species by overfishing and consequent imbalances in reef ecosystems and biodiversity are being undertaken in various parts of the world.  A Canadian researcher, Amanda Vincent, who documented a dramatic decline in seahorses as a result of over-harvest for Chinese Traditional Medicine, has been working with Philippine fishermen to limit catch and set aside sanctuaries where stocks can increase.  Woods Hole and Scripps Oceanographic Institutes are conducting important research in marine environments, studying subjects as diverse as the effects of US Navy sonar testing on whale behavior and deep- sea environments.  Small and maneuverable submarines are now exploring deep- sea ecosystems, taking samples of new species and filming these extraordinary habitats.  Almost all such research is funded by non-governmental organizations, since governments have yet to realize the importance of funding such research.
     International efforts began as early as 1973 to control Marube debris and pollution when the International Maritime Organization, a United Nations agency responsible for shipping, formed an agreement known as MARPOL. This agreement regulated the disposal of oil and hazardous chemicals.  In 1978, it was amended to include annexes on the disposal of hazardous materials, sewage, fishing nets, ropes, bags and trash.  In 1988, the Marine Plastics Pollution Research and Control Act was enacted by Congress, prohibiting United States ships from dumping plastic items into the sea, and prohibiting foreign ships from disposing of plastics within 200 miles of the United States.  Plastics include such items as nylon fishing nets.  As of 1994, all US government-owned ships had to comply with all regulations, disposing of plastic waste at port.  The National Oceanic and Atmospheric Administration (NOAA) has an interagency task force on marine debris, which has attempted to coordinate other federal agencies to reduce marine debris.  The Environmental Protection Agency, with the Center for Marine Conservation, and NOAA coordinate annual beach cleanups, which are now being carried out in some European countries as well as in the Middle Eastern country of Bahrain.  Thousands of tons of plastic bags and fishing lines that might have washed back out to sea have been removed by these cleanups.  The Marine Entanglement Research Program was established by NOAA in 1984 to study this problem.
     As a result of international concern about the disappearance of irreplaceable wetlands, the Ramsar Convention was adopted in 1971.  Each member country designates and accords legal protection for at least one wetland to be included in the List of Wetlands of International Importance.  More than 600 Ramsar sites have been designated, covering 100 million acres.  Some of these wetlands, in spite of designation, are threatened by government-sponsored plans.  The Acheloos Delta in southwestern Greece may be diverted to produce electricity, and a huge flood-control plan threatens Lake Utonai in Japan.  The Ramsar Convention has been instrumental, however, in protecting wetlands through international cooperation.  The Wadden Sea, a wetland on the coasts of the Netherlands, Germany and Denmark with up to 12 million birds wintering, breeding or migrating through its land, is being protected through cooperative agreements among the three countries (Dugan 1993).  These wetlands are not in their natural state after centuries of diking, filling and other man-made changes, but efforts are being made to maintain large areas of marshland and other wetland habitat.
     The North American Wetlands Conservation Act of 1989 created funding to preserve wetlands in Canada, the United States and Mexico; since 1989, hundreds of projects have protected more than 1 million acres of wetland ecosystems in the United States and Canada alone.  A prime area preserved by this act is Cheyenne Bottoms, the last sizeable wetland in Kansas, designated as a "Wetland of International Importance" by the Ramsar Convention, a Hemispheric Reserve by the Western Hemisphere Shorebird Network, and Critical Habitat for the endangered whooping crane (Grus americana).  To date, 6,000 acres have been protected, 35,000 restored and another 13,000 acres of Cheyenne Bottoms enhanced (Graziano 1994). 
      Another important aquatic environment, the lagoons of Baja California, has been designated a Biosphere Preserve.  Under great threat from a proposed salt factory to be constructed by Mitsubishi Corporation in the prime wintering lagoons of gray whales, conservationists succeeded in stopping the project in late 2000.  This preserve also shelters sea turtles, many sea birds and other marine mammals.  Mexico's laws did not permit such damage to an officially declared Biosphere Preserve, but it nevertheless took years of legal wrangling and the participation of many conservation organizations to achieve this victory.
     National anti-pollution legislation in many countries is making some progress in bringing back rivers and wetlands that had become lifeless from heavy pollution.  International treaties have also been negotiated for individual rivers.  The Danube River flows 1,770 miles from its source in Germany to the Black Sea, and along its entire length, it has been diked, dammed and channeled to accommodate barge traffic (Cowell 1995).  In Hungary, the river inspired the famous waltz of that name and has been severely damaged by dams and diversion on the Slovak side, which have shunted most of the water from one of Europe's wildlife havens.  This 200 square mile area is one of Europe's last wetlands, sheltering some 5,000 species of flora and fauna, and Hungary continues to negotiate its return. 
     The Danube Delta on the Black Sea lies mainly in Romania and is considered one of the world's great wetlands, covering 2,200 square miles (Simons 1997).  In the mid-1980s Romania's dictator, Nicolae Ceausescu, decreed that the entire delta be transformed into grain fields (Simons 1997).  He succeeded in destroying about one-fourth of the delta, or 240,000 acres, converting the land into wheat and rice fields.  Not only was massive wildlife habitat lost, but his men shot pelicans and cormorants because they were eating too many fish (Simons 1997).  The drainage plan did not succeed because the delta soil was not conducive to these crops, and by the time Ceausescu was executed by firing squad in 1989, it had been abandoned (Simons 1997). 
     In 1991 the Danube Delta was declared a Biosphere Preserve, and a conservation plan was set in place; as a first act, dikes and dams were breached, allowing the flooding of more than 9,000 acres (Simons 1997). As a feeding and resting area for millions of migratory birds of 325 species, the delta is of global importance (Simons 1997).  It is also a major nesting area for many threatened birds, including the Dalmatian pelican (Pelecanus crispus), a bird that was once abundant throughout Western Europe (Hoyo et al. 1992).  Today, it is confined to eastern Europe and east-central Asia, with approximately 4,000 to 5,000 breeding pairs; fortunately, as a result of strong conservation programs, massive declines have been stopped or slowed (BI 2000).
     An ecotourist industry has sprung up in the Danube Delta, helping to fund further restoration (Simons 1997).  Anti-pollution work will be needed to cleanse the waters of an overload of contaminants poured into the river by the eight countries through which it flows (Simons 1997).  This is the world's first example of the restoration of a delta and is founded on the philosophy that land valuable as flood protection and wildlife conservation is worth more in its natural state than converted for human use (Simons 1997).  Experts involved in Mississippi and Rhine River restoration have been interested in the Danube restoration, which may herald a new approach to this crucial habitat.
Sections of rivers have received protection under the Wild and Scenic Rivers Act.  This law and the actions private organizations such as American Rivers have succeeded in altering the pro-dam and channeling viewpoint that long has dominated America.  The International Rivers Network has also worked to oppose dams around the world, often with great success.  On the local scene, River Network, an organization founded in 1988, works at a grassroots level to encourage citizens to help clean up and preserve rivers and watersheds.  Its book, How to Save a River: A Handbook for Citizen Action (Bolling 1994), provides a blueprint for individual conservationists. The Water Keeper Alliance, first launched to save the Hudson River from heavy pollution, works on many rivers in the United States to test water for pollution and works through activists and lawyers to stop pollution problems (Cronin and Kennedy 1997).  Teachers and their students in countless school districts have adopted streams and rivers, removing trash and debris, and restoring them to their original states, even reintroducing native fish. 
     Progress is also being made in the United States in restoring wetland ecosystems. The Everglades is America's largest wetland.  It was a vast, unspoiled marsh, a wilderness of sawgrass, groves of Bald Cypress trees and vegetated hillocks until only a century ago.  Fresh water flowed through the 7 million acre Everglades from the enormous, 733 square mile Lake Okeechobee and its feeder rivers to the north, ending in Florida Bay (Levin 1996).  During the dry season, rivers threaded their way through the wetland, and in spring wet seasons, the entire region would turn into a shallow river of grass.  At one time, more wading birds nested here than anywhere else in the country.  Four hundred species of birds, 60 species of amphibians and reptiles, and 25 species of mammals have been recorded in the southern Everglades alone, and at least 120 species of trees and 1,000 species of seed-bearing plants are native (Rex 1996). 
Giant century-old alligators (Alligator mississippiensis) prey on a diversity of fish, turtles and snakes.  River otters (Lutra canadensis) and tiny white-tailed deer (Odocoileus virginianus seminola) are also native.  The round-tailed muskrat (Neofiber alleni) is found nowhere else.  This rodent, dependent on shallow, freshwater marshes, has been affected by the invasion of exotic plants that have taken over much of the Everglades (Layne 1978).  The Everglades mink (Mustela vison evergladensis) lives south of Lake Okeechobee, far from other races of mink.  These animals are aquatic, utilizing much the same type of habitat as the round-tailed muskrat, although they are far more restricted in range (Layne 1978).  Both species have declined as a result of development, water pollution and reduction of acreage of the freshwater marshes (Layne 1978).
     Settlers arriving in Florida in the 19th century saw only a "pestilence-ridden swamp."  The US government drained the entire wetland for development and agriculture, building the first federal canal in 1881 with enthusiastic state support.  In 1905, the Governor of Florida vowed to wring the last drop of water out of the Everglades, and state drainage programs supplemented federal projects.  Congress passed legislation in 1947 that authorized a massive program to control the flow of the Everglades, ostensibly to prevent flooding; 1,400 miles of canals, dikes and levees were built to straighten and channel the meandering Kissimmee River, the major feeder of Lake Okeechobee, in order to divert water for sugar growers south of the lake (Levin 1996).  Four canals drained the lake and lowered water level by 5 feet; 3 to 4 million acres of its water were diverted toward the Atlantic every year, water that once fed the Everglades (Levin 1996).  South of the lake, 500,000 acres were drained for agriculture. The same year this project was authorized, a strong-willed newspaper reporter, Marjory Stoneman Douglas (1947), wrote The Everglades: River of Grass, pleading for the preservation of this great wetland.  She carefully researched the conservation importance of the Everglades and documented the folly of destroying it to appease the growing agriculture industry.  The book remains a classic, and not until the 1990s did the country realize that the drainage project was a terrible mistake.  
     Half the wetlands that once made up the Everglades are gone, now replaced by farms, suburban housing, agriculture and highways (Levin 1996).  Ninety percent of the water birds and most of the native mammals have disappeared.  The southern Everglades have become increasingly saline from an influx of sea water, causing the disappearance of many species unable to adapt.  Some of the overflow from canals during heavy rains has been pumped into the Micaseekee Indian Reservation, which is located in the Everglades, flooding buildings and drowning hundreds of deer.  In 1990, outflows drowned 90 percent of the entire deer population in the Everglades.  Entire forests of bald cypress trees have died (Dugan 1993). 
     Wood storks once nested in colonies of 10,000 or more in the swamps northwest of the national park in the Corkscrew Swamp Sanctuary (Toops 1989).  This 10,560-acre National Audubon Society sanctuary now protects 400 or fewer pairs of these birds; storks require shallow, freshwater pools that concentrate fish, especially during nesting season, to feed their young.  Because of the drainage of the agricultural area and the lowering of water levels, wood storks died out and their chicks starved in the nest (Toops 1989).  During the 1930s, at least 75,000 wood storks bred in Florida, but by 1975 there were only 12,000 (Kale 1978).  They continued to decline, and in 1980, only 5,000 pairs remained (Lucas 1996).  In 1984, the US Fish and Wildlife Service added the US population of wood storks to the Endangered Species Act. 
     The loss of water in the Everglades has had dramatic effects on alligators. They grow at abnormally slow rates, are underweight for their age and more anemic than alligators in other parts of the South.  Research on the diet of these reptiles in 1997 revealed they were malnourished.  The once-abundant populations of fish have disappeared, and alligators are forced to scavenge carcasses and feed on small mammals and snakes. 
     Federal protection was accorded to the southernmost 1.5 million acres of the Everglades by establishment of the Everglades National Park, but its ancient water flow pattern has been so disrupted by channeling, diversion and drainage that the ecosystem is a shadow of its former self.  Adjoining the park to the northwest is Big Cypress National Preserve, an area of 570,000 acres also under the jurisdiction of the National Park Service, but with less restrictions; hunting, fishing and even mining are allowed in National Preserves under certain circumstances.
     After 50 years of declining wildlife and proposals to restore the Everglades, Congress passed the Everglades Forever Act of 1994 (Cushman 1996a).  Forty miles of the Kissimmee River, whose huge oxbows and curves through marshy pineland were turned into a diked canal by the US Army Corps of Engineers, will be returned to natural bends by this same agency.  The cost of repairing the damage is an estimated $500 million, 14 times what it cost to obliterate the river's original curves (Levin 1996).  Diking and channeling shortened the river from 103 miles to 56 miles, and a wet prairie where a million ducks wintered was drained (Levin 1996).  A recent survey of the area found a total of eight ducks, and droughts in the region have increased (Levin 1996).  Some local ranchers oppose the plan, but it has received the support of conservationists and, after intense lobbying, of President Bill Clinton.  The nearby National Audubon Society's Kissimmee Prairie Preserve nearby, protects 8,000 acres of the original 30,000-square-mile flood plain of this river (Levin 1996). 
     Under the 1994 Everglades Forever Act, 40,000 acres of the agricultural lands will also be restored to marsh.  A 3-mile-wide flow-way from Lake Okeechobee into the Everglades is another facet of the restoration plan.  This would revive marshes below the lake.  Sugar farmers have protested government acquisition and resent the proposed controls on the amounts of fertilizers and pesticides that can be released into the water system.  The sugar industry in Florida receives $1.4 billion per year in federal tax breaks, and it has balked at any loss in its economic status.  Added to the loss of acreage, the industry was angered by a proposed "sugar tax" that would have raised $245 million over a seven years to restore the Everglades (Levin 1996).  Political contributions of more than $15 million from the sugar industry to presidential and other politicians’ campaigns to represent their case have stymied efforts to restore this internationally important wetland.  The funding was dealt a severe blow in November 1996 when Florida voters rejected the sugar tax plan on the Presidential ballot.
     Funding by the Congress, which voted $7.8 billion for the Everglades Restoration Fund in 2000, permitted the project to go forward (Schmitt 2000).  Florida will pay half of this sum over the next 40 years to redirect 80 percent of water now diverted back to the Everglades through an untested system of quarries and aquifers, and by removal of dikes and barriers (Schmitt 2000).  The plan may not succeed in its goal of restoring the original ecosystem, but water flow will be improved, allowing wildlife to recover some of their populations.  In another positive decision, plans that called for turning Homestead Air Force Base at the edge of the Everglades near Miami into an international commercial airport with hotels, development and new roads were canceled in early 2001 by the Clinton Administration (Canedy 2001).
     Cleaning up Florida Bay and returning the sea grass to dead areas is another project that began in the 1990s, but it lacks the funding of the Everglades restoration.  Its western portion is now saturated with algae, and the native turtle grass has disappeared from large areas (Stevens 1997).  The tourist industry centered on snorkeling and diving is in decline as a result.  A lack of fresh water has caused increased salinity and a resultant influx of water laden with agricultural chemicals.  This aggravates the growth of algal blooms, such as red tide.  Endangered sea turtles inhabit Florida Bay, and the coral reefs are home to a great diversity of fish and invertebrates, all of which are in steep decline.
     The tourist industry brings $13 billion to Florida each year, a large percentage from Everglades tourists and others who come to appreciate the coral reefs and wildlife.  This should impact decisions made to save the Everglades National Park, surrounding wetlands and Florida Bay.
     The restoration of the Everglades represents an about-face for the historical approach to wetlands in the United States, and it may be copied in other parts of the country.  Wetlands legislation still includes certain concepts such as "mitigation," a legal loophole allowing destruction of one marsh or wetland if another is preserved or created.  Many ecologists consider that the natural wetland is far more complex and irreplaceable than the man-made one, and they should not be considered equal under the law (Daily 1997, Williams 1996).  These man-made wetlands often fail to function naturally, and the concept of allowing such wetlands to be constructed when natural wetlands are destroyed is flawed. Developers often construct new wetlands in unnatural blocks without proper natural hydrology or native plants and animals.
     Non-governmental organizations, such as The Nature Conservancy and the International Crane Foundation (ICF), have played a significant role in preserving many threatened wetland habitats for birds.  The demilitarized zone between North and South Korea is a major refuge for cranes, white-tailed sea eagles and other water birds.  Rare white-nape cranes (Grus vipio) were discovered feeding in the Han River estuary just south of the zone prior to the diking of these marshes for rice production.  Dr. George Archibald, co-founder of ICF, and Korean ornithologist Kim Hon Kyu, convinced the South Korean government to set aside this marsh.  Other key wildlife wetlands under threat have been preserved through the diplomacy of these conservation organizations and cooperation between biologists and governments that have bridged old enmities.
     The problem of sewage and runoff from roadways, agricultural fields and suburban housing areas will only grow in the future.  A US government project to deal with this problem has used natural solutions that could be imitated elsewhere.  The project constructed shallow basins to capture runoff that then flows through grass, which removes solids and nutrients, and then to a cattail marsh for further cleansing.  The last step is a deep pond with fish and mussels, which filter the water.  Ten of these systems have been installed in Maine at a very small cost of $14,000 to $35,000, and similar structures have been built in New Jersey, New York and Massachusetts (Williams 1996).  A new treatment process, vermifiltration, in which earthworms in soil filters extract nutrients and suspended matter from sewage, produces an effluent free of pathogens and ideal for irrigation. Several towns and cities in California have created marshes to filter sewage that has been given secondary treatment.  These have become wildlife havens and even tourist attractions.  By contrast, Boston constructed a 9-mile pipe to carry treated sewage into Cape Cod Bay, where over 300 million gallons will be dumped each day, posing a threat to fisheries and other wildlife.  Its cost was $390 million.  Some cities have tapped sewage for methane gas to power city facilities. 
     Scientists are now attempting to address the problem of soil salinization with salt-resistant plants.  Department of Agriculture research has also found river reeds that turn toxic chemical runoff into water and carbon dioxide, poplar trees that absorb pollutants from groundwater, and grains and grasses that absorb fertilizer and herbicides, breaking down the toxins (Howe 1997).  Prevention and care to avoid such pollution before it happens is even more important for the future.
     The facilities for the 2000 Olympic Games at Sydney were designed to be environmentally sensitive.  Recycled storm water was used for toilet flushing, and sewage effluent was filtered and recycled (Zuckoff 2000a).  A degraded creek was restored to its former state, and when the rare Bell frog (Litoria aurea), was discovered on the site of the tennis center, special tunnels were built to allow these frogs to move through it unharmed (Zuckoff 2000a).  This center did not create oily residue from automobiles on asphalt parking lots because these were the first Olympic Games to ban all internal combustion cars, requiring travel by trains that connected facilities and solar cars built for the games (Zuckoff 2000a).
     Conservationists in the future will need to overcome the effects of a global economy spurred by corporate profits and politicians pushing destructive water projects through legislatures, only to repay financial contributions made to their campaigns or political favors done for them.  Extraordinary wildlife habitats can be destroyed with the stroke of a pen.  The Copper River Delta of Alaska is a large wetland vital to millions of waterfowl, shore birds and marine mammals, but politicians have proposed construction of a road through it for the benefit of loggers who want to remove timber. 
     With the warming of the global climate, ship traffic through the Arctic Ocean will increase, and the vast river deltas and waterfowl habitat in northern Canada will soon be threatened by oil tankers and construction of gas pipelines and roads.  This region is vital habitat for a large percentage of the continent's waterfowl and shore birds, polar bears (Ursus maritimus), whales, seals, walrus and fish.  Diamond mining and other development are already encroaching on this pristine area.
     The extent of our interference with natural ecosystems is undoubtedly adversely affecting evolution.  Nature has evolved superb adaptations in aquatic species, survivors for millennia within their habitats.  We are just beginning to appreciate and understand the great diversity in aquatic ecosystems and the awe-inspiring beauty here.  It is vital that this new understanding be used to protect, not destroy.

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