Everglades Wetlands

• Category: Inland Aquatic Biomes
• Geographic Location: North America
• Summary: The Florida Everglades is a flowing “river of grass” and an international treasure, threatened by agricultural and residential development and by climate change.

The Everglades was once an 11,000-square-mile (28,500-square-kilometer) wetlands and body of water flowing through much of southern Florida and into the Gulf of Mexico and Atlantic Ocean. While somewhat diminished from its original state, this still-vast ecosystem supports an abundance of wildlife, including such hallmark species as roseate spoonbills, wood storks, alligators, crocodiles, and manatees. The habitats here are rich and diverse—but the Everglades was once viewed as a large swath of underdeveloped real estate.

This established the goal of drastically altering the area's hydrology to create dry land that could be used for agriculture and municipal water supply endeavors. While this process has supported a large sugarcane industry and great population growth, the ecosystem has suffered lost habitat and declines in water quality. A slow but continuous national effort has helped restore water flow through the Everglades and ensure the ecosystem's viability is sustained.

Ecologic and Cultural History

As early as 128,000 years ago, during the Pleistocene Epoch, most of the Everglades were completely submerged as a lagoon resting on an expansive limestone bed. As the sea levels receded, the Everglades formed approximately 5,000 years ago. From near the center of Florida's vast and highly flat peninsula, a vast expanse of freshwater seeped and flowed through much of the southern half, traveling 100 miles (161 kilometers) from Lake Okeechobee to Florida Bay. This unusual wetlands ecosystem has withstood several different land uses, known by different cultures as The Lake of the Holy Spirit, Grassy Water, River Glades, and Everglades.

The first to discover the value of the Everglades, about 1,000 B.C.E., were the Calusa Indians, a highly organized people who crafted shell tools and extensive canoe trails, consuming aquatic animals such as fish, turtles, alligators, and shellfish. After being challenged by other tribes, the Calusa and the Miccosukee sought refuge in the Everglades and safety in the peninsula's vast prairies and mangrove swamps.

When European colonizers discovered the marshy expanse, the development of farmland and water draining began. By the mid-1800s, the consensus was that the Everglades was a useless swamp and should be drained; in 1850, the U.S. Congress authorized the Swamp and Overflowed Lands Act, transferring 20 million acres (8.1 million hectares) of such land from federal to state control for purposes of drainage.

The Big Drain

In 1904, recently elected Florida Governor Napoleon Bonaparte Broward pledged to create a dry Empire of the Everglades. The state established drainage districts and installed canals to remove water from the land. Farmers began converting the River of Grass into a sea of vegetables, sugarcane, and sod. Sugarcane was one of the first large commercial industries in the region, established by 1920. Towns boomed, but in the late 1920s, two hurricanes devastated built-up areas. As a result, the Hoover dike was built in the mid-1930s, to reduce the impact of storm flooding.

Natural disasters were common in this region. In the 1950s, residents of southern Florida experienced considerable flooding and hurricanes, large wildfires, and droughts. These weather episodes led Congress to authorize the Central and Southern Florida Project. This massive flood control undertaking would ensure sustained supplies of water to the growing population and the agricultural industry. Development meant that less water would be available for the ecosystem and the habitats within it, however. While this was a large project designed to serve a population of two million, the rapid growth in this region ultimately mandated providing for the water needs of some six million people.

Drastic Impact

The Everglades are half the size they were in 1900. Many species that once called the Everglades home are extinct or extirpated in the area. The Everglades Wetlands biome receives less than one-third of its historic water flow, and much of this water is contaminated by fertilizer and other runoff.

Wading bird populations have declined by as much as ninety-five percent as water and habitat availability shrank. Nearly 68 plant and animal species today are threatened and endangered. Approximately 1.7 billion gallons (6.4 billion liters) of water per day used to be stored and utilized by the ecosystem is now channeled directly into the ocean. Because this runoff is often polluted with nutrients and toxic products used in agriculture, lawn care, and municipal functions, the fish populations and seagrasses are declining in the Florida Bay estuaries. Due to its diversion for human use, the lower water flow in some areas has set the scene for saltwater intrusion into the supply system, wreaking havoc upon some habitats.

In the mid-1980s, phosphorous originating from the Everglades Agricultural Area's sugarcane fields and Lake Okeechobee led to large algal blooms. For four years, 1988–92, the cane industry resisted accepting responsibility for this pollution and fought attempts by both state and federal governments to regulate this nutrient material. Separately, mercury contamination was accumulating from power plant emissions.

Fauna

IIn addition to development and agriculture, the pet trade has disrupted this ecosystem. In particular, non-native snake species such as the Burmese python and boa constrictor are commonly released by owners when they become too large. A report by the National Academy of Sciences found that these escapees had, within a decade, wiped out 99 percent of raccoons, opossums, and other small and medium-sized mammals across great swaths of the Everglades, as well as 87 percent of bobcats. In early 2012, the federal government approved a bill to ban the sale of imported snakes, including Burmese pythons, northern African pythons, southern African pythons, reticulated pythons, green anacondas, yellow anacondas, Beni or Bolivian python, DeSchauensee's anaconda, and boa constrictor. In 2022, Governor Ron DeSantis announced record-level funding to restore the Everglades and the removal of the Burmese python.

An International Treasure

Even through the decades of heavy damage, not everyone viewed the Everglades as a place to drain and develop. In 1934, Congress officially declared portions of the Everglades a national park. Later, President Harry S. Truman dedicated 1.3 million acres (526,000 hectares) of land to the park. Internationally, the Everglades is designated a Biosphere Reserve, a World Heritage site, and a Wetland of International Importance. The Everglades National Park is one of the rare places in the world where alligators and crocodiles coexist.

The Everglades is interspersed with a number of unique habitats. Many of its marshes are sawgrass marshes, places where few animals or other plants thrive, though alligators often choose these locations for nesting. Freshwater sloughs are deeper than marshes and are areas of free-flowing water in between the marshes. The borders between these systems are called “ridge-and-slough” landscapes. Aquatic animals such as turtles, young alligators, snakes, and fish live in sloughs and usually feed on aquatic invertebrates, such as the Florida apple snail. On the ridge zones are wet prairies, which being elevated tend to support a higher diversity of creatures than sawgrass marshes.

Drier lands surround these habitats. Tropical hardwood hammocks are elevated areas that support a wide range of trees, including strangler fig, mahogany, and other terrestrial life. Pine forests and cypress swamps border the prairies and sloughs. Pine forests are highly susceptible to fire but require this process to maintain their health. The Big Cypress ecosystem measures about 1,200 square miles (3,100 square kilometers) and supports abundant associated vegetation and animals.

Water from Lake Okeechobee and The Big Cypress eventually flows to the ocean. At this point, the Everglades transitions to mangroves, which thrive throughout freshwater, brackish water, and saltwater. The Everglades have some of the world's most extensive contiguous systems of mangroves. Besides supporting many faunal communities, these groves buffer inland systems from hurricanes and sea-level rise.

Restoring the Flow

In 1983, newly elected Governor Bob Graham announced the formation of the Save Our Everglades campaign with the goal of restoring the Everglades to its condition as of 1900. A part of the plan was the restoration of the Kissimmee River, in which Graham lifted the first shovel of backfill in 1985 to transform the canal into a meandering river again. Later, in 1994, Governor Lawton Chiles introduced the Everglades Forever Act, aimed specifically at water-quality improvement within the Everglades Agricultural Area, which was still heavily burdened by pollutants and excess nutrients released into the lower Everglades.

In 1995, a Commission for a Sustainable South Florida report detailed the degradation of the Everglades and noted that continued deterioration would cause a significant decrease in both tourism with a loss of 12,000 jobs and $200 million annually, and commercial fishing with a loss of 3,300 jobs and $52 million annually. The report stated that the ecosystem and surrounding areas had reached a tipping point, where the health and economy of millions of people were at risk.

In 2000, the federal government approved the Comprehensive Everglades Restoration Plan (CERP) and included more than sixty components, which would take thirty years and cost $9.5 billion to implement. The goal of the CERP is to preserve, protect, and restore the Everglades, along with other parts of central and southern Florida, covering more than 18,000 square miles (47,000 square kilometers). The CERP plan was designed to capture freshwater that currently flows into the Gulf of Mexico or Atlantic Ocean and store or redirect it to areas of need, particularly to fragile ecosystems. The rest of the water will go toward human supplies.

In 2012, Department of the Interior Secretary Ken Salazar established a preserve named Everglades Headwaters National Wildlife Refuge and Conservation Area. It was created to filter pollutants, protect wildlife, reduce development, and provide water for Lake Okeechobee. Property owners, primarily in the agriculture industry, will have the option of making easements available for restoration, while allowing for room to raise livestock or plant crops. If the property owners take full advantage of this opportunity, the total area could encompass as much as 150,000 acres (61,000 hectares).

President Joe Biden allotted considerable funding for the restoration of the Everglades. On January 19, 2022, the Biden administration announced plans to spend $1.1 billion on combating climate change and protecting biodiversity in Everglades. Biden's proposed budget for 2023 included an additional $407 million for Everglades restoration. The latest funding included plans to continue designing an enormous embankment for the 11,000-acre reservoir. The reservoir is used to store and treat water and to send more clean water to the Everglades National Park.

Environmental Future

The Everglades was once completely submerged by freshwater. Rising emissions, especially carbon dioxide from fossil fuel consumption over the last few decades, are leading to an overall warming trend that will increase ocean water expansion and contribute to the melting of ice sheets. As this occurs, sea levels will rise globally and contribute to the loss of some of the Everglades. For example, the entire Everglades National Park lies at or close to sea level. Sixty percent of the park is less than three feet (one meter) above mean sea level, and the highest portion is eleven feet (3.4 meters) above sea level. 

If this occurs, ten to fifty percent of the park's freshwater marsh would be transformed by saltwater pushed landward by rising seas. If the transition occurs slowly, mangroves may be able to hold off some of the impacts, but this is unlikely if the change is more rapid. The future of the Everglades is unknown, but restoration efforts will contribute to its health and resilience to the effects of the changing climate.

Bibliography

Batzer, Darold P., and Andrew H. Baldwin, editors. Wetland Habitats of North America: Ecology and Conservation Concerns. University of California Press, 2012.

"Governor Ron DeSantis Announces 2022 Florida Python Challenge." Florida Fish and Wildlife Conservation Community, 16 June 2022, myfwc.com/news/all-news/python-challenge-622/. Accessed 9 Nov. 2024.

Grunwald, Michael. The Swamp: The Everglades, Florida, and the Politics of Paradise. Simon & Schuster, 2006.

Levey-Baker, Cooper. "How Climate Change Threatens the Everglades." Sarasota, 27 Feb. 2020, www.sarasotamagazine.com/travel-and-outdoors/2020/02/how-climate-change-threatens-the-everglades. Accessed 9 Nov. 2024.

Lodge, Thomas E. The Everglades Handbook: Understanding the Ecosystem. 3rd ed. CRC Press, 2010.

McVoy, Christopher W., et al. Landscapes and Hydrology of the Predrainage Everglades. University Press of Florida, 2011.