Our directory of things of interest

University Directory

Everglades: go with the flow

  • Written by  Daniel Allen
  • Published in Water
Everglades: go with the flow Daniel Allen
03 Jan
Ongoing restoration projects are breathing new life into Florida’s Everglades

As dawn breaks, the alligators below Pahayokee Boardwalk are in full voice. It’s mating season in the Everglades National Park, and the local complement of testosterone-filled males is in full display mode. That means jaw snapping, torso vibrating, and a surprisingly unreptilian chorus of bellows, grunts and growls.

Jack Roark, a National Park Service volunteer, is guiding a group of journalists on an early morning tour. The Everglades veteran has seen this kind of showboating many times before.

‘To me, the male alligator chorus sounds like a group of motorcycles starting up in the distance,’ says the amiable retiree. ‘It’s just one curious natural phenomenon among hundreds in this amazing wetland environment.’

The Everglades is a truly unique ecosystem. Covering more than 2,000 square miles of the southern Florida peninsula, the so-called ‘river of grass’ stretches from Lake Okeechobee in the north to the Gulf of Mexico in the south.

As an International Biosphere Reserve, World Heritage Site and Wetland of International Importance, the Everglades National Park attracts over one million visitors each year.

‘What many of these people don’t realise is that the Everglades is actually a giant waterway, up to 60 miles wide and as shallow as six inches,’ says Roark. ‘The story of this giant wetland – its decline and gradual comeback – is essentially a story of water flow.’

everglades crocThe Everglades are home to a range of wildlife, from alligators to cormorants (Image: Daniel Allen)


Flow interrupted

It may conjure up images of a Stygian swamp, but in reality the Everglades is made up of a diverse patchwork of habitats. Fields of dense, razor-sharp sawgrass are divided by open water channels, or ‘sloughs’, with a scattering of ‘hammocks’ (tree islands) rising dome-like above the surrounding grass and water. This environment is home to predators such as black bears, alligators, crocodiles and pumas, as well as a bountiful array of other fauna and flora.

Yet despite its biological richness, the Everglades is now a fraction of what it once was. Over the last century this vast, intricate system of connected waterways has undergone a process of continual contraction, as various anthropogenic impacts have taken their toll. A network of canals and levees, built to drain water for flood control, water supply, agriculture and rapid urban development, continues to starve the region of slow-moving water.

‘Over half of the original land mass and 70 per cent of the historic water flow to the Everglades National Park have now been lost,’ says Cara Capp, Everglades Restoration Program Manager with the National Parks Conservation Association (NPCA), an independent organisation working to protect America’s national parks.

Today the Everglades represents one of the most highly regulated and controlled watersheds in the world. Thanks to intensive agriculture and urban development, what water that does enter the ecosystem is typically saturated with nutrients and other pollutants. Large-scale tampering with local hydrology has seriously affected local wildlife, both on land and offshore.

‘Local wading bird populations have declined, while 68 plant and animal species are classified as threatened or endangered,’ says Jenn Miller, Public Affairs Specialist with the United States Army Corps of Engineers (USACE). ‘We’ve also seen declining estuary health and marine fisheries as a result of large freshwater discharges.’



Record-breaking restoration

When describing the Everglades, people tend to employ superlatives. This is the largest protected wilderness east of the Mississippi, and the biggest subtropical wetland in North America. Since the turn of the millennium, it has also witnessed the largest ecosystem restoration effort ever attempted.

This effort is being led by two organisations that know the hydrology of South Florida intimately; the USACE, which built most of the canals and levees in the Everglades in the first half of the 20th century, and the South Florida Water Management District. The former issued its rehabilitation blueprint – the Comprehensive Everglades Restoration Plan (CERP) – in 1999.

Comprising more than 50 major projects to be constructed over three decades, the cost of the original CERP was estimated at nearly $8billion. According to recent revisions, the plan will now take approximately 50 years to implement, and could cost upwards of $10billion. Nevertheless, the goal remains the same – the complete restoration of the entire Everglades ecosystem.

‘The primary goal of the CERP is to “get the water right”,’ explains USACE’s Miller. ‘Essentially this means delivering the right amount and quality of water to the right places at the right time. Considering the sheer size of the Everglades, we’re facing a monumental task.’

everglades boatAirboat trips to see the Everglades’ mangrove forests are becoming an increasingly popular source of tourist revenue for the area (Image: Daniel Allen)


The southern imperative

In its early years the CERP was paralysed by a lack of money, bureaucratic procedures and party politics. Today, as new projects break ground and federal and state funding rises to levels not seen since before the global financial crisis, the plan is finally starting to bear fruit.

Much of the CERP’s success to date focuses on Lake Okeechobee. The second largest freshwater lake within the continental United States, this is the liquid heart of the Everglades.

‘Lake Okeechobee is the historical gatekeeper between the watershed from the north of Florida and the southern Everglades and Florida Bay to the south,’ says Miller.

Until a century ago, rain that fell between Orlando and Lake Okeechobee would drain slowly into the lake, where it would be stored. At times of high water, the lake would overflow, replenishing the Everglades with freshwater. At times of low water, the flow would stop, inducing the wetland’s annual dry season. Now when it rains north of Lake Okeechobee, an east-west system of canals – built to protect Floridians from flooding – channel water in the lake rapidly out to sea, water that is bad for estuarine ecosystems, but sorely needed in the Everglades.

‘The overriding objective of the CERP is to get this water to go south again,’ says Dr Steve Davis, an ecologist with the Everglades Foundation, a non-governmental organisation dedicated to protecting and restoring the Everglades ecosystem.

Today algal blooms from phosphorus-laden Lake Okeechobee discharges still plague Florida’s coastal waters. But times are changing. The Kissimmee River, which flows into the lake, has already been transformed back into a naturally functioning river, slowing water flow. Work has also begun on a reservoir below Lake Okeechobee to store water that would otherwise be discharged through canals.

Perhaps the most headline-grabbing triumph of the CERP to date came in April this year. For the first time in decades, water began flowing south into the Everglades once again, under a new, mile-long bridge on the Tamiami Trail. This highway, completed in 1928 to connect Tampa with Miami, had previously blocked all southward flow from Lake Okeechobee. A second, 2.6-mile bridge is now under construction.

Environmentalists, frequently at loggerheads with state and federal water managers, celebrated the opening of the bridge and restored flow as a milestone achievement.

‘Each bridge brings us a step closer to true restoration,’ says the NPCA’s Capp. ‘We have long argued for the full 6.5 miles of bridging that is needed to send enough water through the Everglades National Park and into Florida Bay.’

‘It’s great to see water flowing southward again,’ says Davis. ‘Rerouting freshwater south must be accompanied by efforts to clean the water and reduce the amount of nutrients entering Lake Okeechobee.’


‘The Everglades has a national pull, just like Yellowstone. Most Americans want it saved’


Alien attack

The last thing on Phillip Greenwalt’s mind when he applied for a position in the Everglades National Park was hunting 20-foot, 90-kilogramme snakes. Yet today the park ranger, who works in the Shark Valley District, is becoming something of an expert when it comes to catching elusive reptiles from the jungles of Southeast Asia.

A lack of water and habitat disappearance are not the only problems facing Everglades wildlife. The spread of exotic plant and animal species poses multiple challenges to the success of the restoration effort. Exotic plants now dominate more than 1.5 millon acres of the south Florida ecosystem, while more than a quarter of animal species living here are classified as non-native.

‘South Florida has one of the largest non-indigenous faunal communities in the world,’ says Dr Carol Mitchell, Deputy Director for Science at the South Florida Natural Resources Center (SFNRC). ‘The Everglades is hot, wet and stocked with food. In the case of reptiles, it’s hard to think of a more amenable environment.’

The Burmese python is one reptile that has taken full advantage of such favorable conditions. First recorded in the Everglades in 1979, today the population of these massive constrictors – among the world’s largest snakes – is estimated to number tens of thousands. At maturity, they can consume animals as large as full-grown deer and mature alligators.

Studies suggest that Burmese pythons have had a devastating effect on small mammal populations in the Everglades, some of which have declined up to 90 per cent. Yet while the impact of the snakes is increasingly apparent, fighting back against them is another matter.

‘These animals are incredibly hard to spot,’ says the SFNRC’s Mitchell. ‘They are largely nocturnal and have evolved to be cryptic. For every one you see, there’s probably another hundred that you don’t.’

Increasing efforts are now being made to eradicate the Burmese python, while campaigns continue to educate people about the danger of releasing unwanted pets into the Everglades. Authorised agents may humanely capture pythons and collect data on their locations and habitats, while hunters are also allowed to remove the snakes from wildlife management areas. Earlier this year Florida conducted its second, month-long ‘Python Challenge’, which saw just over a hundred reptiles taken from the wild, up from 68 the previous year.

According to Phillip Greenwalt, the ideal time to hunt Burmese pythons is between 11pm and 4am on moonless nights. ‘The best place to looks for them is actually on the roads that run through the park,’ he says. ‘These cold-blooded animals are attracted to the warmth of roads that have baked in the sun all day. They sit there in the dark waiting to ambush their prey.’

While hunting may have a modest effect on snake numbers, there is, at present, no fully effective solution to the Everglades’ python problem. Researchers don’t even know how to measure the size of the population, or how they might effectively lure the snakes into traps.

‘During 1,000 nights spent trapping pythons, we caught two animals,’ says Mitchell. ‘At the moment, we’re not winning the war.’

‘The consensus is that more resources should be allocated towards control of established invasive species as well as early detection and rapid response measures to prevent future invasions,’ says the Everglades Foundation’s Davis.

Ecologists are now praying that the small mammals upon which the pythons feed – some of which are quite adaptable – will naturally learn how to survive this voracious new predator, before they disappear completely.

everglades pythonBurmese pythons are a particular problem, leading to authorised hunts designed to cull their numbers to manageable levels (Image: Daniel Allen)


Work in progress

As with most massive engineering projects, the restoration of the Everglades is a highly challenging proposition. Apart from the sheer scale of work involved, the CERP must consider the complex and often competing needs of different species, as well as variables such as climate change and urban population growth.

It also has to balance the interests of numerous stakeholders. ‘Stakeholder engagement is and always has been essential in advancing CERP planning and implementation,’ says Davis. ‘More and more people are realising that their livelihoods, even their property values, are tied to the health of the Everglades.’

Even so, pretty much everyone working to restore this unique wetland is fully aware it will never regain its former glory. ‘We’ve lost about half of the natural ecosystem,’ says Davis. ‘We’ll never get that half back. But we can stop haemorrhaging what’s left.’

Everglades restoration brings economic as well as ecological benefits. The wetland recharges South Florida’s water – water that supplies one in three Floridians, as well as the local agriculture and tourism industries. Beyond this, restoration will benefit fishing and other tourism-based recreational activities. ‘Studies show that restoration yields a conservative $4 return on every $1 invested,’ says Davis.

A decade and a half since the CERP began, there is renewed hope that a corner may have just been turned. With more money recently promised for new restoration projects, a mood of cautious optimism now pervades those involved with the plan.

‘Everglades restoration is a long, arduous process,’ says Mitchell. ‘Yet the dedication and cooperation of disparate groups in the battle to save this precious wetland is inspiring. The Everglades has a national pull, just like Yellowstone. Most Americans want it saved.’

This was published in the June 2017 edition of Geographical magazine.

Related items

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in PLACES...


Maida Bilal risked all to prevent contractors building a dam…


Writer and photographer John Gilbey needed a cheap way of…


An EU project has revealed the extent of river fragmentation…


A new, double-sided world map projection seeks to minimise the…


 Water scarcity is predicted to rise – two experts share…


New collaborative research from the University of Oxford and the…


Conceived during the late 1800s, Letchworth Garden City was the…


Multiple failed attempts to build on a patch of land…


New 'deep learning' technology is helping to identify trees in…


The land around the Kinabatangan River in the state of…


Highlights from the column that keeps you connected with the…


At the end of a perplexing and thought-provoking year, we…


The city of Mosul is slowly putting itself back together…


The story of a unique Italo-Slovenian community that came to…


Bisecting Georgia's northwestern region, the Enguri River has come to…


A study in Northern Minnesota is experimentally heating the air…


Some of the quirkiest geopolitical oddities are  Europe’s semi-independent microstates (SIMs). Vitali…


Ninety years after depopulation, the Scottish islands of St Kilda…


Not all passports are created equal