NPS Profile: What's in our wetlands?

Issue 7 > NPS Profile

A blue dayflower in a wetland.

A blue dayflower grows in a thick clump of wetland plants.

NPS photo.

Living communities in the Smokies are made up of many interacting parts: soils, plants, birds, mammals, invertebrates, microscopic organisms, water, and more. The Inventory and Monitoring (I & M) program has people from varied backgrounds who specialize in studying each of these individual parts. Their specialized knowledge contributes to our understanding—and protection—of the ecosystem as a whole. Right now, I & M is leading a project to find, map, inventory, and monitor the park’s wetlands and associated communities.

Why is it important to monitor wetlands in Great Smoky Mountains National Park?

  • Wetlands are critical habitat for individual rare species, and some of the wetland communities themselves—the collection of plant and animal life existing together—aren’t found in many other places in the world.
  • In the southern Appalachian mountains, we receive massive amounts of air pollution from burning fossil fuels (coal, gasoline, oil). Scientists have measured extremely high amounts of mercury—a toxic chemical—in bird feathers in the park. How does one form of mercury that falls from the sky end up in a harmful form in birds? Wetlands may be the key, serving as a “methylation” site that turns mercury in air to harmful methyl mercury in animals’ bodies.
  • Finally, wetlands are highly sensitive to climate change, and baselines now will help us monitor and understand how shifts in precipitation, temperature, and weather events are changing the park

Here are the multiple steps and scientists involved in inventorying a wetland. Keep scrolling down--it's a long process!

Portion of a map of proposed watersheds to monitor.

Potential watersheds to be included in the new wetland inventory & monitoring.

NPS graphic.

Mapping the park: It isn’t as easy as you may think to locate all of the park’s wetlands. We can’t see most of them on aerial photos, and it’s not feasible to find them by walking all of the park’s 500,000 rugged acres. Therefore, resource managers need a reliable map to predict where wetlands might be. Even then, some of the likely sites are so remote that it takes scientists at least two days to reach and explore them.

Before anyone packs a bag or leaves the office, they consult maps that the park’s GIS specialist, Ben Zank, creates using a GIS (Geographic Information System) program. The maps show elevation and terrain (hilly, flat, or in between) and can even show major types of vegetation, temperatures, and soil types of these mountains. Wetlands—including permanent, temporary, and even former wetland habitats—occur at almost all elevations, from high elevation seeps to low meadow marshes. In the Smokies, some wetlands were drained for farmland, but still may be home to, or habitat for, native wetland species.

Conducting a wetland inventory.

Nunally Benzing (L) and Tom Remaley take notes on species composition in a Tennessee wetland.

NPS photo.

Into the field: After mapping and choosing places to visit, managers, seasonal employees, and interns head out into the field to verify—check—the maps. They carry GPS (Global Positioning System) units, field guides, cameras, and collection materials such as plastic bags, small shovels, and knives. If they’re hiking out to a remote site, they have full packs with tents, sleeping bags, stoves, food, and water filters, too. Once they drive (or boat or hike) to the wetland, they check for signs of rooting, digging, and torn up ground: damage from feral hogs. If they find any, they will report it to the park’s wildlife biologist, Bill Stiver.

The scientists’ main job, once they check for threats, is to map the perimeter of the wet area and take soil, plant, and water samples. These will tell them whether this area is a perennial wetland, meaning it has water year round, year after year, or if it is simply land that is wet after heavy rains or spring snow melt. These temporary wetlands are ephemeral, which means they appear during the spring snowmelt, or have water sometimes throughout the year, but aren’t a reliable habitat for wetland obligates—plant, animal, and invertebrate species that can only live in a wetland. Ephemeral wetlands are vital breeding sites for animals such as wood frogs, which lay their eggs in gelatinous masses in the water, and as a water source for animals (including human-hikers). The type of soil the scientists find, the characteristics of the water, and the presence of certain wetland obligates tell them whether the land qualifies as a wetland.

Fern at edge of wetland.

Fern found at edge of wetland.

NPS photo.

Inventory: If scientists have found a wetland, it’s time to begin planning for the inventory to list of all the species here and monitoring to set up ways to watch its health over the years. Tom Remaley and his staff of biological technicians and interns are one of the first crews to study a new wetland. They set up plots—small, regularly shaped areas of ground—and identify every single plant species that exists there.

This list forms the baseline of native plant species. Scientists will return in future years to see how number, type, or health of species might have changed from this point. They’ll also keep an eye out for any non-native, invasive plants that push native plants out of their habitat, and report it to vegetation manager Kristine Johnson.

Swamp milkweed is rare in the park.

Swamp milkweed is a rare wetland plant in the park.

NPS photo.

Rare plants: Wetlands in the Smokies are often home to rare plants. Botanist Janet Rock explores a new wetland to identify any rare plant populations. If there are any, she comes up with a plan to protect them and a timescale for how often they should be monitored.

Animals: Perennial wetlands are also home to a great diversity of invertebrates (animals with an external skeleton, such as insects and crustaceans), some of which are endemic to the park. Endemics are special because this area—either the park or the larger southern Appalachian area—is the only place they exist in the world! Park entomologist Becky Nichols specializes in studying aquatic macroinvertebrates, and collects, identifies, and guides protection of these water creatures.

Butterflies in Smokies collection.

Butterflies in the Smokies natural history museum collection.

NPS photo.

Specimens: As the inventory is taking place, scientists collect voucher samples of unique plants and invertebrates. These will be carefully mounted and catalogued, and added to the park’s natural history collection. Curator Adriean Mayor adds to, organizes, and curates (cares for) the collection housed at the Twin Creeks Science Center. This collection stands out as one of the oldest and most complete collections in the entire national park service, and, like the inventory itself, will serve as a valuable baseline for future scientists to study park ecosystems.

Looking to the future: The final step—for now, at least, is to take the field and museum data and put it into maps and datasheets. These records, combined with descriptions of plants and animals that scientists found, will let people in the future know the types and numbers of species, where they thrived, what they looked like, and how that baseline may be changing through time.

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