Everglades National Park

Everglades National Park
IUCN category Ib (wilderness area)
Location	Florida, USA
Nearest city	Florida City Everglades City
Area	1,508,571 acres (610,497 hectares) 1,494,970 acres (604,993 ha) federal
Established	December 6, 1947
Visitors	954,022 (in 2006)
Governing body	National Park Service

An ibis takes flight in Everglades National Park

Everglades National Park is a national park in the state of Florida. The largest subtropical wilderness in the United States, it contains the southern 25 percent of the original Everglades marshland region of southwestern Florida. Visited by one million people each year, it is the third-largest national park in the lower 48 states after Death Valley National Park and Yellowstone National Park. It has been declared an International Biosphere Reserve, a World Heritage Site, and a Wetland of International Importance.

Unlike most other U.S. national parks, Everglades National Park was created to protect a fragile ecosystem instead of safeguarding a geographic feature. Thirty-six species designated as threatened or protected live in the park, including the Florida panther, the American crocodile, and the West Indian manatee. Protecting the largest U.S. wilderness area east of the Mississippi River, the park is the most significant breeding ground for tropical wading birds in North America, and contains the largest mangrove ecosystem in the western hemisphere. More than 350 species of birds, 300 species of fresh and saltwater fish, 40 species of mammals, and 50 species of reptiles live within Everglades National Park. All of southern Florida's fresh water is recharged by the park, including that of the Biscayne Aquifer.

The Everglades is a slow-moving system of rivers, flowing southwest at about a quarter of a mile per day, fed by the Kissimmee River and Lake Okeechobee. Although humans have lived in the Everglades for thousands of years, it was not until 1848 that the region began to be drained for agricultural or residential use, and the water flow from Lake Okeechobee was controlled, and diverted to the South Florida metropolitan area. The ecosystems in Everglades National Park have suffered significantly from human activity, and the repair and restoration of the Everglades is a politically charged issue in South Florida.

Climate and geology

Map of Everglades National Park

Everglades National Park covers 1,509,000 acres (611,000 ha), throughout three Florida counties: Dade, Monroe and Collier. The elevation typically ranges from 0 to 8 feet (2.4 m) above sea level, but a Native American-built shell mound on the Gulf Coast rises 20 feet (6.1 m) above sea level. The park's dry season lasts from December to April, when temperatures vary from 53 °F (12 °C) to 77 °F (25 °C) and humidity is low. Since water levels are low at that time, animals congregate at central water locations, providing popular opportunities for viewing the wildlife. During the wet season, from May to November, temperatures are consistently above 90 °F (33 °C) and humidity over 90 percent. Storms can drop 10 to 12 inches (300 mm) of rain at a time, providing half the year's average of 60 inches (152 cm) of rainfall in just two months.

Florida was once part of the African portion of the supercontinent Gondwana. About 200 million years ago, volcanic activity began around Florida's east side, adding massive igneous rock over the sedimentary terrain existing from Gondwana. Continuing activity forced North America away from Pangea; by the late Jurassic period, the Florida peninsula was exposed, but earth and climate cooling submerged it during the Cretaceous period. Sediments that rested over the shallow ocean floor were converted into limestone and related rocks, and the southern portion of Florida formed thicker limestone platforms. One example is the Sunniland Formation, which appeared about 135 million years ago. It lies approximately 2 miles (3.2 km) beneath the Big Cypress Swamp and the western Everglades, and contains a modest amount of oil.

The Everglades appeared above sea level between 100,000 and 15,000 years ago. The land was formed as limestone originally developed under seawater by the abundant calcium carbonate. As ocean water became captured in the polar icecaps, sea levels fell and exposed more land, forming areas that rise above others, called keys. The majority of Everglades National Park rests on the Miami Limestone, formed during the Sangamon interglacial period. The southwestern area of the park covers the Tamiami Formation, a collection of carbonate and sand 150 feet (46 m) thick, which is the source of bedrock beneath the Big Cypress. Tiny bits of shell and sand compressed over multiple layers formed unique limestone structures called ooids. These ooids cemented into the Miami Oolite, which served as a building material for early homes in the South Florida region, and covers most of Everglades National Park and Florida Bay. As more land became exposed, plants began to migrate, some from the northern part of Florida, and some carried as seeds by birds from islands in the Caribbean.

Unlike in the northern portion of Florida, no underground springs feed water into the Everglades system. An underground reservoir called the Floridan Aquifer lies about 1,000 feet (300 m) below the surface of South Florida. However, the Everglades has an immense capacity for water storage, due to the sponge-like permeable limestone underneath the exposed land. Most of the water arrives in the form of rainfall, and a significant amount is stored in the limestone. Water evaporating from the Everglades becomes rain over metropolitan areas, providing the fresh water supply for the region. Water also flows into the park from Lake Okeechobee and the Kissimmee River; rain falling on those areas can appear in the Everglades days later. Water overflows Lake Okeechobee into a river 40 to 70 miles (110 km) wide, which moves almost imperceptibly. The National Park Service recognizes eight distinct ecosystems in the park, which are defined by a constantly changing terrain dependent upon weather elements and the amount of water received by the Everglades.

Park ecology

Tropical hardwood hammocks

Hammocks are often the only dry land within the park. They rise several inches above the grass-covered river, and are dominated by large live oak trees. The taller trees often form canopies under which animals thrive amongst scrub bushes of wild coffee, white indigoberry, poisonwood and saw palmetto. The park features thousands of these tree islands, which often form the shape of a teardrop when seen from above (see park map) because of the slowly moving water around them. Trees, including wild tamarind and gumbo limbo, rarely grow higher than 50 feet (15 m) due to wind, cold weather, and lightning strikes.

Fewer than 100 Florida panthers still exist in the wild.

The plant growth around the hammock base is nearly impenetrable; however, an ideal habitat for animals exists inside the island and under the canopy. Reptiles (such as various species of snake and anole) and amphibians (such as the American green tree frog) find their homes in the hardwood hammocks. Birds such as barred owls, woodpeckers, cardinals, and Southern bald eagles nest in trees of the region. Mammal species living in hardwood hammocks include opossums, raccoons, bobcats, Everglades mink, marsh rabbits, white-tailed deer, and the rare, critically endangered Florida panther.

Pineland

Often called pine rockland, the pineland ecosystem is characterized by shallow dry sandy loam over a limestone substrate covered almost exclusively by slash pines. Trees grow in solution holes, where the soft limestone has worn away and filled with soil, allowing trees and plants to take hold. South Florida slash pines are uniquely adapted to promote fire by existing in beds of dried pine needles and shedding dry bark. Pine cones require the heat from fires to open. However, the bodies of slash pines are resistant to fire, so prescribed burns in these areas take place every three to seven years. Most plants in the area bloom about 16 weeks after a fire. Nearly all pinelands have an understory of palm shrubs, but wild herbs in these areas are diverse.

A variety of animal species meet their need for food, shelter, nesting, and rooking in pine rocklands. Woodpeckers, meadowlarks, shrikes, grackles, and mockingbirds are commonly found in pinelands. The Florida black bear and the Florida panther live in this habitat as well. The pine rocklands are considered one of the most threatened habitats in Florida; less than 4,000 acres (16 km²) of pineland exist in Florida, located entirely within Everglades National Park. Dade County was once covered in pine rockland forests, but most of it was harvested by the lumber industry.

Mangrove and cypress

Mangrove trees along the coastline protect the shore from erosion.

Several species of mangrove trees, which thrive in salt water and brackish water, act as a nursery for many marine and bird species. They are also Florida's first defense against the destructive forces of hurricanes, absorbing flood waters and preventing coastal erosion. Due to their high tolerance of salt water, winds, extreme tides, high temperatures, and muddy soils, mangrove trees are uniquely adapted to extreme conditions. The mangrove system in Everglades National Park is the largest continuous system of mangroves in the world.

There are 220 species of fish living in the Florida mangrove systems, along with a variety of crabs, crayfish, shrimp, mollusks, and other invertebrates, which serve as the main source of food for many birds. Dozens of bird species use mangroves as nurseries and food stores, including pelicans, grebes, tricolored herons, gulls, terns, hawks and kites, and arboreal birds like mangrove cuckoos, yellow warblers, and white-crowned pigeons. The mangroves also support 24 species of amphibians and reptiles, and 18 species of mammals, including the endangered green sea turtle, Hawksbill turtle, and West Indian manatee.

Cypress trees, conifers that are adapted to thrive in standing fresh water, grow in compact structures called cypress domes and in long strands over limestone. Water levels may fluctuate dramatically around cypress domes and strands, so cypresses develop "knees" that protrude from the water. Dwarf cypress trees grow in drier areas with poorer soil. Air plants called epiphytes, such as bromeliads, Spanish moss, orchids and ferns grow on the branches and trunks of cypress trees. Everglades National Park features twenty-five species of orchids. Tall cypress trees provide excellent nesting areas for birds including wild turkeys, ibis, herons, egrets, anhingas, and belted kingfishers. Mammals in cypress regions include white-tailed deer, squirrels, raccoons, opossums, skunks, swamp rabbits, river otters, and bobcats, as well as small rodents.

Coastal lowlands

Coastal lowlands, or wet prairies, are found between mangroves and pine rocklands. These areas may be covered in floodwaters, or remain dry during times of low water. Floods occur during hurricane and tropical storm surges, when ocean water can rise several feet over the land. Heavy rainy seasons also cause floods when rain from the north flows into the Everglades. Few trees thrive in this region, but plants?—such as succulents like saltwort and glasswort—tolerate both salt and brackish water, as well as desert conditions. Animal life in this zone is dependent upon the amount of water present, but commonly found animals include Cape Sable seaside sparrows, Everglades snail kites, Florida grasshopper sparrows, wood storks, eastern indigo snakes, and small mammals such as rats, mice, and rabbits. Florida panthers only rarely visit this region.

Freshwater sloughs and marl prairies

Alligators thrive in freshwater sloughs and marl prairies.

Freshwater sloughs are perhaps the most common ecosystem associated with Everglades National Park. These drainage channels are characterized by low-lying areas covered in fresh water, flowing at an almost imperceptible 100 feet (30 m) per day. Shark River Slough and Taylor Slough are significant features of the park. Sawgrass growing to a length of 6 feet (1.8 m) or more, along with broad-leafed marsh plants, are so prominent in this region that they gave the Everglades its nickname "River of Grass". Excellent locations for bird rookeries, sloughs in the Everglades attract a great variety of wading birds such as herons, egrets, roseate spoonbills, ibises and pelicans, as well as limpkins and snail kites that eat apple snails, which in turn feed on the sawgrass. The sloughs' availability of fish, amphibians, and young birds attract a variety of freshwater turtles, alligators, water moccasins, and rattlesnakes. Crocodiles coexist with alligators in Everglades National Park, the only place in the world where they do so naturally.

A great blue heron wading in a pond near Shark Valley

Freshwater marl prairie is similar to the slough, but lacks the slowly-flowing water; instead, water seeps through porous limestone coverings called marl. Algae and other microscopic organisms attached to limestone form a poor soil that resembles gray mud. Sawgrass and other plants are shorter in freshwater marl, but aquatic plants and periphyton, a complex combination of various types of algae, are much more noticeable. The prairie is usually under water from three to seven months of the year. Animals living in the freshwater sloughs also inhabit in the marl prairie. Alligators burrow in the mud during the dry season, creating trails by walking through the sawgrass and other vegetation. These trails are in turn used by other animals to migrate through the park.

Marine and estuarine

The largest body of water within the park is Florida Bay, which extends from the mangrove swamps of the mainland's southern tip to the Florida Keys. Over 800 square miles (2,100 km²) of marine ecosystem lies in this range. Coral, sponges, and seagrasses serve as shelter and food for crustaceans and mollusks, which in turn are the primary food source for larger marine animals. A massive die-off of seagrasses occurred in 1987, further endangering manatees and sea turtles. Sharks, stingrays, and barracudas also live in this ecosystem, as do larger species of fish that attract sport fishing. Pelicans, shorebirds, terns, and skimmers are among the birds frequenting park shorelines.

Human history

Native people

The sun sets over Shark River Slough.

Humans likely first inhabited the South Florida region 10,000 to 20,000 years ago. Two tribes of Native Americans developed on the peninsula's southern tip: the Tequesta lived on the eastern side and the Calusa, greater in numbers, on the western side. The Everglades served as a natural boundary between them. The Tequesta lived in a single large community near the mouth of the Miami River, while the Calusa lived in 30 different villages. Both groups traveled through the Everglades, but rarely lived within them, remaining mostly along the coast.

The diets of both groups consisted mostly of shellfish and other fish, small mammals, game, and wild plants. Having access only to soft limestone, most of the tools fashioned by Native Americans in the region were made of shell, bone, wood, and animal teeth; shark teeth were used as cutting blades, and sharpened reeds became arrows and spears. Shell mounds still exist today within the park, giving archaeologists and anthropologists evidence of the raw materials available to the indigenous people for tool construction. Spanish explorers estimated the number of Tequesta at first contact to be around 800, and Calusa at 2,000, although the National Park Service reports there were probably about 20,000 natives living in or near the Everglades when the Spanish established contact in the late 1500s. The Calusa society was more advanced, as they lived in social strata, and were able to create canals, earthworks, and shellworks. The Calusa were also able to resist the first Spanish attempts at conquest.

Although the Spanish had contact with these societies, they established missions further north, near Lake Okeechobee. In the 1700s, invading Creeks incorporated the dwindling numbers of the Tequesta into their own. Neither the Tequesta nor Calusa tribe existed by 1800. Disease, warfare, and capture for slavery had effectively eradicated both groups. The only evidence of their existence within the park boundaries is a series of shell mounds that were built by the Calusa.

In the early 1800s, Creeks, escaped African slaves, and other Indians from northern Florida displaced by the Creek War formed the area's Seminole nation. After the end of the Seminole Wars in 1842, the Seminoles faced relocation to Oklahoma. A few hundred Seminole hunters and scouts settled within what is today Big Cypress National Preserve, to escape the emigration to the west. From 1859 to about 1930, the Seminoles and Miccosukee, a similar but linguistically unique tribe, lived in relative isolation, making their living by trading. In 1928, surveying and construction began on the Tamiami Trail, along the northern border of Everglades National Park. The road not only bisected the Everglades but also introduced a steady, if small, traffic of European settlers into the Everglades.

Some members of the Miccosukee and Seminole tribes continue to live within park boundaries. Management of the park includes approval of new policies and procedures by tribal representatives "in such a manner that they do not conflict with the park purpose".

American settlements

Following the end of the Seminole Wars, Americans began settling at isolated points along the coast in what is now the park, from the Ten Thousand Islands to Cape Sable. Communities developed on the two largest pieces of dry ground in the area, on Chokoloskee Island and at Flamingo on Cape Sable, both of which established post offices in the early 1890s. Chokoloskee Island is a shell mound, a midden built roughly 20 feet (6 m) high over thousands of years of occupation by the Calusa. The settlements in Chokoloskee and Flamingo served as trading centers for small populations of farmers, fishermen and charcoal burners settled in the Ten Thousand Islands. Both settlements and the more isolated homesteads could only be reached by boat until well into the 20th century. Everglades City, on the mainland near Chokoloskee, enjoyed a brief period of prosperity when, beginning in 1920, it served as the headquarters for construction of the Tamiami Trail. A dirt road from Florida City reached Flamingo in 1922, while a causeway finally connected Chokoloskee to the mainland's Everglades City in 1956. After the park was established, residents of Flamingo were bought out, and the site was incorporated into the park as a visitor center.

Land development and conservation

A canal lock being constructed in the Everglades in 1906

Several attempts were made to drain and develop the Everglades from the 1850s to the 1890s. The first canals built in the Everglades did little harm to the ecosystem, as they were unable to drain much of it. However, Napoleon Bonaparte Broward based the majority of his campaign for governor on how drainage would create "The Empire of the Everglades". Broward oversaw the drainage between 1905 and 1910, and was successful enough that land developers sold tracts for $30 an acre, settling the town of Davie, and developing regions in Lee and Dade counties. The canals also cleared water that made way for agricultural fields growing sugarcane.

The 1920s saw a population boom in South Florida that created a demand for land described by author Michael Grunwald as "insanity". Land was sold before any homes or structures were built on it, and in some cases before any plans for construction were in place. New landowners, eager to make good on their investments, hastily constructed homes and small towns on recently drained land. Mangrove trees on the coasts were taken down for better views and replaced with shallow rooted palm trees. The U.S. Army Corps of Engineers began construction on larger canals to control the rising waters in the Everglades. Nevertheless, Lake Okeechobee continued to rise and fall, the region was covered with rain, and city planners continued to battle the water. The 1926 Miami Hurricane caused Lake Okeechobee levees to fail; dozens of people who had just moved in south of the lake drowned. Two years later, the 1928 Okeechobee Hurricane claimed 2,500 lives when Lake Okeechobee once again surged over its levees. Politicians who declared the Everglades uninhabitable were silenced when a four-storey wall, named the Herbert Hoover Dike, was built around Lake Okeechobee. This wall effectively cut off the water source from the Everglades.

Following the wall's construction, South Florida endured a drought severe enough to cause massive wildfires in 1939. The influx of humans had a detrimental effect on the plants and animals of the region when melaleuca trees were introduced to help with drainage, along with Australian pines brought in by developers as windbreaks. The region's timber was devastated for lumber supplies. Alligators, birds, frogs, and fish were hunted on a massive scale. People claiming to be Audubon Society wardens shot entire rookeries of wading birds to collect plumes. However, the largest impact people had on the region was the diversion of water away from the Everglades. Canals were deepened and widened, and water levels fell dramatically, causing chaos in food webs. Salt water replaced fresh water in the canals, and by 1997 scientists noticed that salt water was seeping into the Biscayne Aquifer, South Florida's water source.

In the 1940s, a freelance writer and former reporter for The Miami Herald named Marjory Stoneman Douglas began to research the Everglades for an assignment about the Miami River. She studied the land and water for five years, and published The Everglades: River of Grass in 1947, describing the area in great detail, including a chapter on its disappearance. She wrote: "What had been a river of grass and sweet water that had given meaning and life and uniqueness to this enormous geography through centuries in which man had no place here was made, in one chaotic gesture of greed and ignorance and folly, a river of fire." The book has sold 500,000 copies since its publication, and Douglas' continued dedication to ecology conservation earned her the nicknames "Grand Dame of the Everglades", "Grandmother of the Everglades" and "the anti-Christ" for her singular focus at the expense of some political interests. She founded and served as president for an organization called Friends of the Everglades, initially intended to protest the construction of a proposed Big Cypress jetport in 1968. Successful in that confrontation, the organization has grown to over 4,000 members, committed to the preservation of the Everglades. She wrote and spoke about the importance of the Everglades until her death at age 108 in 1998.

Park history

Everglades National Park

UNESCO World Heritage Site
Criteria	Natural: viii, ix, x
Reference	76
Inscription	1979 (3rd Session)
Endangered	1993–2007

Floridians hoping to preserve at least part of the Everglades first proposed that the area become a national park in 1923. Five years later, the Florida state legislature established the Tropical Everglades National Park Commission to study the formation of a protected area. The commission was led by a land developer turned conservationist named Ernest F. Coe, who was eventually nicknamed "Father of Everglades National Park". Coe's original plan for the park included more than 2,000,000 acres (810,000 ha) including Key Largo and Big Cypress, and his unwillingness to compromise almost prevented the park's creation. Various other interests, including land developers and sport hunters, demanded some of the land be trimmed.

The commission was also tasked with proposing a method to raise the money to purchase the land. The search coincided with the arrival of the Great Depression in the United States, and money for land purchase was scarce. The U.S. House of Representatives authorized the creation of the new national park on May 30, 1934, but it passed only with a rider that ensured no money would be allotted to the project for at least five years. Coe's passion and U.S. Senator Spessard Holland's politicking helped to fully establish it, after Holland was able to negotiate 1,300,000 acres (5,300 km²) of the park, leaving out Big Cypress, Key Largo, the Turner River area, and a 22,000-acre (89 km²) tract of land called "The Hole in the Donut" that was too highly valued for agriculture. Miami Herald editor John Pennekamp was instrumental in pushing the Florida Legislature to raise $2 million to purchase the private land inside the park boundaries. It was dedicated by President Harry Truman on December 6, 1947, one month after Douglas' book was released. In the same year, several tropical storms struck South Florida, prompting the construction of 1,400 miles (2,300 km) of canals, sending water unwanted by farmers and residents to the ocean.

Little had changed by the 1960s, when the park was in danger because of the diversion of water to metropolitan areas. Although the U.S. Army Corps of Engineers was directed to provide enough water to sustain the park, the Corps did not follow through. Political battles were fought over the amount of water the park was receiving, while some of its rivers and lakes became muddy puddles. In 1972 a bill was introduced to curb development in South Florida and ensure the national park would receive the amount of water it needed. Efforts turned to repairing the damage wrought by decades of mismanagement: the Army Corps of Engineers changed its focus in 1990 from constructing dams and canals to constructing "purely environmental projects".

Regions originally delineated by Ernest Coe were slowly added over the years to Everglades National Park, or incorporated into other protected areas: Biscayne National Park, Big Cypress National Preserve, John Pennekamp Coral Reef State Park on Key Largo, Ten Thousand Islands National Wildlife Refuge, and "The Hole in the Donut" were all protected after the park's opening in 1947. Everglades National Park was designated an International Biosphere Reserve on October 26, 1976. On November 10, 1978, most of the park was declared a wilderness area. Wilderness designations covered 1,296,505 acres (5247 km²) in 2003—about 86 percent of the park. It was listed as a UNESCO World Heritage Site on October 24, 1979 and as a Wetland of International Importance on June 4, 1987.

Restoration efforts

President George H. W. Bush signed the Everglades National Park Protection and Expansion Act on December 13, 1989 that added 109,506 acres (443.16 km²) to the eastern side of the park, closed the park to airboats, directed the Department of the Army to restore water to improve the ecosystems within Everglades National Park, and "Direct(ed) the Secretary of the Interior to manage the Park in order to maintain the natural abundance, diversity, and ecological integrity of native plants and animals, as well as the behavior of native animals, as part of their ecosystem." Bush remarked in his statement when signing the act, "Through this legislation that river of grass may now be restored to its natural flow of water". In 1993, however, the park was placed on the List of World Heritage Sites in danger.

In 2000, Congress approved a federal effort to restore the Everglades, named the Comprehensive Everglades Restoration Plan (CERP), with the objectives of "restoration, preservation and protection of the south Florida ecosystem while providing for other water-related needs of the region", and claiming to be the largest environmental restoration in history. It was a controversial plan; detractors worried that it "relies on uncertain technologies, overlooks water quality, subsidizes damaging growth and delays its environmental benefits". Supporters of the plan included the National Audubon Society, who was accused by Friends of the Everglades and the Biodiversity Legal Foundation of prioritizing agricultural and business interests.

CERP projects are designed to capture 1.7 billion gallons (6.4 billion l) of fresh water every day, store it in underground reservoirs and release the water to areas within 16 counties in South Florida. Approximately 35,600 acres (14,400 ha) of man-made wetlands are to be constructed to confine contaminated water before it is released to the Everglades, and 240 miles (390 km) of canals that divert water away from the Everglades are to be destroyed. During the first five years of implementation, CERP was responsible for the purchase of 207,000 acres (840 km²) of land at a cost of $1 billion. The plan aims to spend $10.5 billion over 30 years, combining 50 different projects and giving them 5-year timelines. If the State of Florida does not meet the timelines set by CERP, federal justices are able to terminate the settlement and stop federal funding of the restoration projects. Because of the projects, Everglades National Park was removed in 2007 from the List of World Heritage Sites in danger.

A little blue heron hunting near water on Anhinga Trail.

Everglades National Park was directly hit by Hurricanes Katrina, Wilma, and Rita in 2005. Such storms are a natural part of the park's ecosystem; 1960's Hurricane Donna left nothing in the mangroves but "standing dead snags" several miles wide, but 30 years later the area had completely recovered. Predictably, what suffered the most in the park from the 2005 hurricanes were manmade structures. The visitors center and lodge at Flamingo were damaged by 125 mph (201 km/h) winds and an 8 ft (2.4 m) storm surge. As of 2007 the lodge remained closed, and the visitor's center was significantly damaged, open only during the busy season from December to March.

Park economics

Everglades National Park reported in 2005 a budget of over $28 million. Of that, $14.8 million is granted from the National Park Service, and $13.5 million from various sources including CERP, donations, and other grants. The entry fee for vehicles in 2006 ranged from $10 to $200 for bus tours. Of the nearly one million visitors to Everglades National Park in 2006, more than 38,000 were overnight campers, paying $16 a night or $10 a night for backcountry permits. Visitors spent $2.6 million within the park and $48 million in local economies. More than 900 jobs were sustained or created within or by the park, and the park added value of $35 million to local economies.

Activities

The busiest season for visitors is from December to March, when temperatures are lowest and mosquitoes are least active. The park features four visitor centers: on the Tamiami Trail (part of U.S. Route 41) directly west of Miami is the Shark Valley Visitor Center. A five-mile (8 km) path leads from this center to a two-story observation tower. Tram tours are available during the busy season. Closest to Homestead on State Road 9336 is the Ernest F. Coe Visitor Center, where a 38-mile (61 km) road begins, winding through pine rockland, cypress, freshwater marl prairie, coastal prairie, and mangroves. Various hiking trails are accessible from the gravel road, which runs to the Flamingo Visitor Center and marina, open and staffed during the busiest times of the year. The Gulf Coast Visitor Center is closest to Everglades City on State Road 29 along the west coast. The Gulf Coast Visitor Center gives canoers access to the Wilderness Waterway, a 99-mile (160 km) canoe trail that extends to the Flamingo Visitor Center. The western coast of the park and the Ten Thousand Islands, as well as the various key islands in Florida Bay, are accessible only by boat.

Trails

A view of vast sawgrass expanse north of Anhinga Trail gives visitors an opportunity to see a freshwater slough up close.

Several walking trails in the park vary in walking difficulty on Pine Island, where visitors can cross hardwood hammocks, pinelands, and freshwater sloughs. Starting at the Royal Palm Visitor Center, the Anhinga Trail is a half-mile self-guided tour through a sawgrass marsh where visitors can see alligators, marsh and wading birds, turtles, and bromeliads. Its proximity to Homestead, Florida and its accessibility make it one of the most visited sites in the park. The Gumbo Limbo Trail is another self-guided trail, half a mile long. It loops through a canopy of hardwood hammocks that include gumbo limbo, royal palms, strangler figs, and a variety of epiphytes. 28 miles (45 km) of trails start near the Long Pine Key campgrounds and wind through Long Pine Key, well-suited for offroad cycling through the pine rocklands in the Marjory Stoneman Douglas Wilderness Area. Two boardwalks allow visitors to walk through a cypress forest at Pa-Hay-O-Kee, which also features a two-story overlook, and another at Mahogany Hammock that takes hikers through a dense forest in the middle of a freshwater marl prairie. Closer to Flamingo, more rugged trails take visitors through mangrove swamps, and along Florida Bay. Christian Point Trail, Snake Bight Trail, Rowdy Bend Trail and Coastal Prairie Trail allow viewing of shorebirds and wading birds along mangroves. Portions of the trails may be closed due to hurricane damage, and ranger-led tours take place in the busier season only.

Camping and recreation

Camping sites are available year-round in Everglades National Park. Frontcountry camping, with some services, is available at Long Pine Key, close to the Ernest F. Coe Visitor Center, where 108 sites are accessible by car. Near Flamingo 234 campsites with some services are also available. Recreational vehicle camping is available at these sites, although not with all necessary services. Backcountry permits are required for campsites along the Wilderness Waterway, Gulf Coast sites, and sites in the various keys. Several backcountry sites are chickees; others are beach and ground sites.

Low-powered motorboats are allowed into the park, although the majority of salt water areas are no-wake zones to protect manatees from harm. Jet skis, airboats, and other motorized personal watercraft are prohibited. However, many trails allow kayaks and canoes. A state license is required for fishing, and although fresh water licenses are not sold in the park, a salt water license may be available. Swimming is not recommended within the park boundaries, since water moccasins, snapping turtles, alligators and crocodiles thrive in fresh water; and sharks, barracuda, and sharp dangerous coral are plentiful in salt water. Visibility is low in both kinds.

Threats to the park and ecology

Diversion and quality of water

Bromeliads flourish on cypress trees as a great egret passes.

Less than 50 percent of the Everglades which existed prior to drainage attempts remains intact today. Populations of wading birds have dwindled 90 percent from their original numbers. The diversion of water to South Florida's still-growing metropolitan areas is the Everglades National Park's number one threat. In the 1950s and 1960s, 1,400 miles (2,300 km) of canals and levees, 150 gates and spillways, and 16 pumping stations were constructed to direct water toward cities and away from the Everglades. Low levels of water leave fish vulnerable to reptiles and birds, and as sawgrass dries it can burn or die off, which in turn kills apple snails and other animals that wading birds feed upon. Entire populations of birds disappeared in the 1960s, but The Miami Herald reported in 2006 that populations of wading birds had risen significantly; although park managers are optimistic, they hesitate to declare the bird populations recovered.

The west coast of Florida relies on desalinization for its fresh water; the quantity demanded is too great for the land to provide. Nitrates in the underground water system and high levels of mercury also impact the quality of fresh water the park receives. In 1998 a Florida panther was found dead in Shark Water Slough, with levels of mercury high enough to kill a human. Increased occurrences of algae blooms and red tide in Biscayne Bay and Florida Bay have been traced to the amounts of controlled water released from Lake Okeechobee. The brochure given to all visitors at Everglades National Park includes a statement that reads, "Freshwater flowing into the park is engineered. With the help of pumps, floodgates, and retention ponds along the park's boundary, the Everglades is presently on life support, alive but diminished."

Urban encroachment

A series of levees on the park's eastern border marks the line between urban and protected areas, but development into these areas threatens the park system. Florida still attracts nearly a thousand new residents every year, and building residential, commercial and industrial zones near Everglades National Park stresses the water balance and ecosystems within the park. On the park's western border, Ft. Myers, Naples and Cape Coral are growing, but no system of levees exists to mark that border. National Geographic rated both Everglades National Park and Big Cypress National Preserve the lowest-scoring parks in North America, at 32 out of 100. Their scoring system rated 55 parks in terms of sustainable tourism, destination quality, and park management. The experts who compiled the results justified the score by stating: "Encroachment by housing and retail development has thrown the precious ecosystem into a tailspin, and if humankind doesn't back off, there will be nothing left of one of this country's most amazing treasures".

Endangered and threatened animals

The American crocodile has notable differences from the alligator. Habitat destruction and vehicle collisions are its biggest threats.

Thirty-six federally protected animals live in the park, some of which face grave concern for survival. The American crocodile is found only in South Florida within the United States. Overhunted for their hides, today they are protected from hunting, but are still threatened due to habitat destruction, and injury from cars when they cross roads to reach waterways. Roughly 50 nests exist in Everglades and Biscayne National Parks, and about 1,000 crocodiles currently live in Florida. Numbers of crocodiles in South Florida have risen recently along with the numbers of alligators, and crocodiles were reclassified as "threatened" in the United States in 2007.

The Florida panther is one of the most endangered mammals on earth, and they live only in the Everglades. Fewer than 100  live in the wild. The biggest threats to the panther include habitat destruction from human development, vehicle collisions, inbreeding due to a limited gene pool, parasites, diseases, and mercury poisoning.

Four species of sea turtles including the Atlantic green sea turtle, Atlantic hawksbill, Atlantic loggerhead, and the Atlantic ridley are endangered, and the leatherback sea turtle is threatened. Although numbers are difficult to determine, since males and juveniles do not return to their birthplace, females lay eggs in the same location every year. Habitat loss and illegal poaching and destructive fishing practices are the biggest threats to these animals.

Two species of birds in the park are most in danger of disappearing. The Cape Sable seaside sparrow is the only bird restricted to Everglades National Park. In 1981 there were 6,656 Cape Sable seaside sparrows reported in its boundaries, but surveys over 10 years documented a decline to an estimated 2,624 birds by 2002. Attempts to return natural levels of water to the park have been controversial; Cape Sable seaside sparrows nest about a foot off the ground, and rising water levels may harm future populations, as well as threaten the endangered snail kite. The Everglades snail kite eats apple snails almost exclusively, and the Everglades is the only location in the United States where this bird of prey exists. There is some evidence that the population may be increasing, but loss of habitat and food sources keep the estimated number of these birds at several hundred.

The West Indian manatee has recently been upgraded from endangered to threatened. Collisions with boats and habitat loss are still its biggest threats.

Drought, fire, and rising seal levels

Fire naturally occurs after lightning storms, but takes its heaviest toll when water levels are low. Hardwood hammock and cypress trees are susceptible to heavy damage due to fire, and some may take decades to grow back. Peat built up over centuries in the marsh can cause fires to burn deep scars in the soil. In 2007, Fred Sklar of the South Florida Water Management District said: "An extreme drought can be viewed almost as catastrophic as a volcano. It can reshape the entire landscape. It can take 1,000 years to produce two inches of peat, and you can lose those couple of inches in a week."

Rising sea levels caused by global warming are another threat to the future of the park. Since 1932, ocean levels at Key West have steadily risen over 0.7 feet (0.2 m), which could have disastrous consequences for land so close to the ocean. It is estimated that within 500 years freshwater habitats in the Everglades National Park will be obliterated by salt water, leaving only the northern-most portion of the Everglades. Cost estimates for raising or replacing the Tamiami Trail and Alligator Alley with bridges are in the hundreds of millions of dollars.

Non-native species

An aerial view of the southwestern tip of Everglades National Park

Another growing threat in recent years is the introduction of non-native species into the park. The melaleuca tree causes the most destruction of any plant species, taking large amounts of water and leaving marsh areas desiccated. Brazilian pepper has invaded as well, competing with native plants that serve as food for animals, and is difficult to eradicate. The Burmese python is one of the most formidable animal species. These snakes are capable of growing up to 20 feet (6.1 m) in length, and park visitors have seen them struggling with alligators. As Kenneth Krysko from the Florida Museum of Natural History puts it, "These [snakes] are now the huge apex predator in the Everglades. There's nothing bigger." The first python was found in 1979, with none seen until 1995; between 2001 and 2005, however, more than 230 pythons have been discovered within the park boundaries, and they have begun reproducing on their own. When found, pythons are immediately captured and removed. Park biologists say that the exotic pet trade and pet owners who release pythons into the wilderness are responsible for the existence of the snakes within the Everglades. Skip Snow, wildlife biologist at Everglades National Park, said, "All of the Burmese pythons that we see in the park are a product of the international pet trade." Coyotes have also been spotted in the park, as well as in Big Cypress National Preserve. Park managers have attributed to the lower numbers of wild pigs in both parks to the arrival of coyotes.

See also

• Comprehensive Everglades Restoration Plan
• Nike Missile Site HM-69
• Dry Tortugas National Park
• Biscayne National Park
• Big Cypress National Preserve

Bibliography

• Douglas, Marjory. (1947) The Everglades: River of Grass. Florida Classics Library. ISBN 0912451440
• Grunwald, Michael. (2006) The Swamp: The Everglades, Florida, and the Politics of Paradise. Simon & Schuster. ISBN 9780743251051
• Lodge, Thomas. (2005) The Everglades Handbook: Understanding the Ecosystem. CRC Press. ISBN 1566706149
• Robertson, Jr. William. (1989) Everglades: The Park Story. Florida National Parks & Monuments Association, Inc. ISBN 0945142013
• Tebeau, Charlton W. (1955) The Story of the Chokoloskee Bay County and the reminiscenses of pioneer C. S. "Ted" Smallwood. University of Miami Press.
• Tebeau, Charlton W. (1963) They Lived in the Park: The Story of Man in the Everglades National Park. University of Miami Press.
• Tebeau, Charlton W. (1968) Man in the Everglades. University of Miami Press. ISBN 9780870240737
• Whitney, Ellie et al., eds. (2004) Priceless Florida: Natural Ecosystems and Native Species. Pineapple Press, Inc. ISBN 9781561643097

External links

• Official site: Everglades National Park
• The Everglades in the Time of Marjorie Stoneman Douglas Photo exhibit created by the State Archives of Florida
• Reclaiming the Everglades: South Florida's Natural History
• Everglades National Park Protection and Expansion Act
• The Comprehensive Everglades Restoration Plan (CERP)
• UNESCO World Heritage Centre
• Marjory Stoneman Douglas Wilderness