Florida’s rare ghost orchids are getting cut off from water

Human activities are threatening these stunning, strange flowers, just as scientists are beginning to understand them.

Photograph by Mac Stone
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The rare ghost orchid grows primarily in three protected areas in South Florida. Its stunning flowers have enchanted people around the world.

Photograph by Mac Stone

Florida’s rare ghost orchids are getting cut off from water

Human activities are threatening these stunning, strange flowers, just as scientists are beginning to understand them.

The ghost orchid is an unusual, and unusually beautiful, flower found only in Cuba and the flooded forests of South Florida, where there are about 2,000 of the plants. This species, which draws its moisture from the air, has no leaves. Rather, its green stems cling like bits of linguine to trees, anchoring it to its host. Most of the year, the ghost orchid is unremarkable.

But when it blooms, it stuns. The flower is a striking white, standing out against the shaded green swamps it calls home. Its petals have two long, delicate tails that flutter in the breeze, and it seems to hover in the air. An umbrella species, the ghost orchid survives only in intact forests with high levels of humidity, which protect it from winter freezes, drought, and wildfire.

One of the only places you can easily see a ghost orchid is the Corkscrew Swamp Sanctuary, the United States' largest old-growth bald cypress forest. And the draw here is no ordinary ghost orchid but a massive plant known as the "super ghost." Found 50 feet up a cypress tree—a position that has protected it from poachers—visitors can behold it through a spotting scope on site.

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The ghost orchid is not the only air plant, or epiphyte, that lives in swamps and flooded forests. The lush canopies of old-growth cypress provide ideal habitat and microclimates for a number of other rare epiphytes, like this yellow helmet orchid (Polystachya concreta).

This super ghost, which may consist of multiple intertwined plants, produces more than 40 flowers in summer and can easily have up to 10 or more in bloom simultaneously.

“That’s just insane,” says photographer Mac Stone, as most ghost orchids in the wild put out one or two flowers at a time.

But this super ghost, and other ghost orchids, may be in trouble. New research shows that Corkscrew is drying out. Its marshes and seasonally flooded forests now experience longer dry periods, dry out more quickly, and have less water overall, according to a new paper published in the journal Wetland Science & Practice.

While the paper, co-authored by Shawn Clem, the sanctuary’s research director, and hydrologist Michael Duever, focuses only on Corkscrew Swamp, scientists and conservationists say that most of Florida’s ghost orchids are threatened by the same problem—land use changes and development are limiting water flow to the critical habitats where they’re found.

Threat of development

Florida’s ghost orchids are mostly found in protected areas: national wildlife refuges, state preserves and state forests, and private sanctuaries like Corkscrew. All these places have what orchids and other air plants, or epiphytes, need—high humidity caused by standing water during the wet season, which starts in late spring and lasts through fall. (Learn how to photograph an orchid from a National Geographic photographer.)

Historically, ghost orchids have been able to survive the dry season because it didn’t last long enough for them to dry out. In Corkscrew, for example, from 1960 to 2000, the water ran dry in the cypress forests for two months of the year at most, according to the study. But in recent years, Corkscrew sees more than three parched months a year. In some places, it’s potentially enough to harm the plants, says Peter Houlihan, a conservation scientist and National Geographic Explorer who studies the orchids.

“Historically, that would’ve never happened,” Houlihan says. These dry spells can cause local die-offs of ghost orchids. “It’s just an example of how delicate the ghost orchid is.”

Clem and Duever’s paper suggests multiple causes for the reduction in water, most of which are linked to development. These causes include diversion by canals (which keep water off of roads and out of neighborhoods), increased extraction by suburbs and agriculture, and less green space for water storage. A lack of natural fires has also driven a change in plant cover from grasses to large plants like shrubs that use more water.

It’s a lesson that we can’t merely create a wildlife preserve and sit back, says Clem. The plants, animals, and entire ecosystem still must be defended from threats outside the sanctuary’s boundaries.

“We can’t just put a fence around a place and assume it will solve all problems. We need to think about how we’re managing the water” and protecting its flow, says Robert Sobczak, a hydrologist with Big Cypress National Preserve, home to about a thousand ghost orchids, the most found anywhere.

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Pond apple trees are important hosts for ghost orchids. They're able to survive long periods of flooding, and their thick canopies help create the ideal microclimate for the orchids.

Development beyond borders

Almost all the places in Florida where ghost orchids are found have had their hydrology altered by development in surrounding areas. In Big Cypress, for example, the landscape is significantly drier in the last 15 years than it has been historically, he says.

“It’s currently a dry October,” Sobczak says over the phone, while visiting a cypress dome, one of the large circular stands of trees found throughout the preserve. “This dome should be filled.” While he can’t yet draw a direct connection from the lack of water to dying ghost orchids in Big Cypress, it does have him and his colleague Tony Pernas worried.

“I am concerned,” says Pernas, a botanist and chief of resource management at the preserve. “Ghost orchids have a niche in the deeper water areas of the swamp, so even a few-inch decline in water levels could lead to wildfires that could destroy their population.” Just in the past two years, blazes have swept through 30,000 acres of Big Cypress, much of it prime ghost orchid habitat.

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A boardwalk winds through Corkscrew Swamp Sanctuary and its wet prairie, marshes, and the world's largest stand of virgin cypresses.

The situation is more urgent in Picayune Strand State Forest. Like elsewhere in the area (except Corkscrew), its old-growth cypress forests were logged in the 1940s and 1950s. Shortly thereafter, canal-building and road development began for a planned community called Southern Golden Gate Estates, which was envisioned as the largest subdivision in the world. The plan eventually fell apart, but the draining of this area and the subsequent lowering of the water table have seriously harmed its plant life, including its ghost orchids, according to Mike Owen, a biologist with Fakahatchee Strand State Preserve, just to the east of Picayune.

“Picayune doesn’t have a lot of ghost orchids anymore, though they used to,” Owen says. “That’s due in part to reductions in the hydroperiod,” he adds, referring to the period when the ground is covered in water. The shorter hydroperiod, he says, is caused by a series of canals still found on the property.

Flow to Fakahatchee Preserve and the Florida Panther Wildlife Refuge, which together are home to about half of the state’s ghost orchids, also lose water to a canal along State Road 29. This two-lane thoroughfare, which the state wants to widen to four lanes, runs north from Everglades City on the coast to the southwest interior, shunting water away from conservation lands and into the ocean.

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The "super ghost" is the largest known ghost orchid in the wilds of South Florida, putting out many blooms at a time, sometimes for much of the summer.

Reason for hope

Restoration programs and careful planning can help, however. Fakahatchee Strand State Preserve, for example, has plugged two canals that cut through the land and used to divert water to the west. Owen says that since that change, water levels have gone up more than a foot in the preserve, which is infamous as the location where a man named John Laroche was arrested in 1994 while attempting to steal ghost orchids and other epiphytes, a tale recounted in The Orchid Thief and the film Adaptation. (Read more: Are traders and traffickers winning the orchid battle?)

“I think it’s a wakeup call” to keep healthy levels of water flowing into protected areas, says Sobczak of the paper by Clem and Duever. While Corkscrew is closer to suburban developments than most of the orchids’ other habitats, subdivisions are spreading. As they inch closer to protected areas, hydrological changes could affect them all.

There’s so much more to learn about the ghost orchid (Dendrophylax lindenii), Houlihan says. That’s why it’s important their habitat is protected. For example, a September 2019 paper by Houlihan, Stone, Clem, Owen, and Thomas Emmel—along with observations by a team led by photographer Carlton Ward in Florida Panther National Wildlife Refuge—showed that ghost orchids are pollinated by more than a single species of moth, as scientists previously believed. This discovery not only provides insight into the plant’s virtually unknown reproductive biology, but it also suggests that conserving the ghost orchid may be less difficult than assumed, because it’s not dependent on only one pollinator. (Read more about the discovery here.)

The plight of the orchid has also prompted several scientists and conservationists to try to get the species protection under the Endangered Species Act. Owen and others are working on producing data to support a proposal for listing, which they hope to submit in the near future. An Endangered Species Act listing for the orchid would give greater protection to its habitat as well.

“We need to protect areas like Corkscrew,” Clem says, “so we can continue to understand the ecology...and conserve some of the really unique wildlife and plants that live here.”