Wildflower is published quarterly by the Wildflower Center. Its content is national in scope with articles about the conservation and use of native plants as well as news from the Wildflower Center. A subscription is provided to Wildflower Center members as a benefit of membership.
Biodiversity is shaping the way we practice conservation
By Nan Booth Simpson
Before the settlers came, waist-high grasses and diverse, colorful prairie wildflowers bloomed in the moist, sandy soil along the Indiana-Illinois border. Long-vanished glacial lakes had produced dunes where sculptural oak barrens thrived. And just 65 miles south of present-day Chicago, great flocks of migrating birds rested in the low marshland and sedge meadows around 20,000-acre Beaver Lake, Indiana's largest body of fresh water.
By 1900 the horizon-to-horizon panorama of native plants had been plowed for corn, beans and wheat. Beaver Lake and its marshes were drained and converted to a network of drainage ditches. Only scattered remnants of the prairie remained, and these tiny isolated leftovers lacked the mass of open space needed to sustain a healthy, diverse habitat.
To begin a healing process, The Nature Conservancy purchased 7,209 acres that had been farmed for a century in the region's Kankakee Sands area. This important acquisition in 1996 produced an explosion of available habitats for many species. Today the property is the heart of a contiguous collection of large preserves totaling 20,000 acres. Stakeholders include local landowners, multiple government agencies that own adjacent properties, and both public and private funding sources.
The plant and animal communities of the Kankakee Sands area differ markedly from their counterparts in nearby deep black-soil prairie habitats. For an authentic ecosystem to be reestablished, the Kankakee species required connections to comparable areas that could be crossed by pollinators. Today, biodiversity is returning to Kankakee Sands.
Shorthand for biological diversity, the word biodiversity was first coined in 1986 when the National Academy of Sciences held its first forum on biodiversity. In 1988, the term gained recognition when Harvard entomologist E. O. Wilson used it as the title of a book he edited on biological diversity. There are now more than 25 million citations for the word on Google alone. The term literally means "variety of life." It embraces not only every species of plant, animal and microorganism, but also the diversity of the genes these species contain and the diversity of the ecosystems in which they exist. Biodiversity also speaks to the diversity of individuals within a species and the diversity of populations of a species within a habitat.
More than just a tally of living things, biodiversity requires us to factor in the mutual dependency of every organism. That the greatest and the smallest of species might be equally important has raised some significant philosophical issues.
In the past, our interest in other species was mostly confined to those that we saw as beneficial to ourselves or those that were in some way endearing to us. Whales and snow leopards are fascinating creatures and infinitely more attractive than nematodes. But advances in technology have shown us that seemingly insignificant creatures play far more vital roles in the environmental equation than anyone ever imagined.
Science also has revealed that there are many, many more species on earth than even biologists considered possible a few years ago. This is obviously good news for mankind. We now know that an obscure marine worm can yield chemical compounds with healing properties and that some previously unknown soil microbes can neutralize toxic waste. No one needs to be told, however, that species are diminishing due to habitat loss, over-harvesting, proliferation of invasive species, climate change and pollution. Ecosystems are being disrupted, often before we can understand the importance of the myriad species that exist within each one.
The Nature Conservancy (TNC), one of the most effective preservation alliances in the world, began in the early 1950s when a group of concerned citizens in New York bought and fenced a pond to prevent development. "We're known as 'the group that buys land,' but the concept of biodiversity has caused us to change tactics," says Valerie Vartanian of TNC's Global Invasive Species Initiative at the Missouri Botanical Garden.
"We now realize that saving one species or fencing off one scenic spot doesn't do the job. Now we are focused on whole-habitat protection. We can't buy every piece of valued land, so we are working with local landowners to protect their own properties. The goal is to maintain healthy ecosystems that not only host a diversity of life but also allow people to make a living on the land."
The organization uses a science-based approach called "Conservation by Design" to determine where to work, what to conserve, what strategies to use and how to measure effectiveness. "We've come a long way since the '60s and '70s, when the knee-jerk reaction was simply to stop the bulldozers," adds Vartanian. "And, as research and experience shows us more about how nature works, we're trying to conserve 'enough of everything,' not just the most rare or imperiled species or places."
Because Kankakee Sands was the most ambitious prairie restoration ever undertaken, TNC secured Applied Ecological Services, Inc. (AES)?as project manager to analyze the site and create restoration and management plans. Employing such high-tech tools as aerial photography and computer modeling, the Wisconsin-based AES team conducted sophisticated hydrological investigations and detailed ecological assessments of the site's dunes, wetlands, grasslands and oak savannas.
The goal was not to restore the lake but to create prairie in its place that would connect the existing natural remnants in the area. In the bed of the former lake, a series of shallow lakes and wet-sand prairie has been formed to provide a hospitable environment for amphibians, birds and animals that require large open spaces.
The project also included the development of a 120-acre native plant nursery to propagate seeds of more than 130 native plant species appropriate for each zone. (400 species were planted on the property; those that did not come from the nursery were collected from wild populations.)
"We used historical accounts to identify species and studied the remnants of plant colonies in the area to help determine where and when to reintroduce the plants," says Chip O'Leary, a site ecologist at Kankakee Sands. He observes that many familiar, flashy prairie plants are populating this landmark restoration effort, but the "real excitement" comes from stands of unusual little species such as flax-leaf aster (Ionactis linariifolius) and cream wild indigo (Baptisia bracteata var. leucophaea). There also have been sightings of endangered plants, including the crowded oval sedge (Carex cumulata), a species that was thought to have disappeared from Indiana.
Birding is now among the preserve's biggest attractions. Bobolinks and dickcissels from South America arrive to breed in summer. Various wading birds such as the American bittern and king rail frequent the shallow marshes, and in 2002 Kankakee Sands hosted a few breeding pairs of Wilson's phalaropes, a wading bird that hadn't been recorded breeding in Indiana for more than 40 years. Short-ear owls are now common in spring and fall, and ground-nesting northern harriers (known also as marsh hawks) can be seen gliding around, on the lookout for mice and other prey.
Recovering populations of reptiles inhabit the sandy marshes. Six-lined racerunner lizards and slender glass lizards (long, legless reptiles that resemble snakes but have blinking eyelids and ear holes) can be found on the property's old dunes. "Blue racer snakes routinely frighten hikers, but there are no poisonous snakes on the property, which is kind of nice," O'Leary admits. Also, endangered regal fritillaries and dusted skippers are among the many species that have staged a significant comeback.
Each year, about 500 acres are cleared and replanted. Two-thirds of the planting project is now completed, although full restoration will take years to achieve. "With a prairie landscape, keeping invasive species out is an ongoing job," says O'Leary. "In the fall, eight to 10 trained people outfitted with fire equipment burn about 1,000 of the replanted acres. Fire beats back all of the brush and non-native cool-season plants," he explains. "Full-time managers are also in charge of herbicide applications, cutting down invasive trees and plugging in prairie plants."
Continuing research at the site ensures accountability. At present, independently funded scientists are studying the birds, insects, reptiles, plants and beneficial soil fungi. As researchers acquire more knowledge, the project managers keep supplementing the specifications for restoration. Even within the unspoiled remnants of tall grass prairie, there were wide variations in plant associations. Each hill or depression resulted in the growth of different plants. "There's still a lot to learn," says O'Leary. "There's so much neat stuff hiding out there."Biologist Deborah Marr, associate professor at Indiana University South Bend, along with her colleague Andy Schnabel and geneticist Rebecca Dolan at Butler University in Indianapolis, collaborated on a research project at Kankakee Sands to determine whether the genetic diversity and species diversity of seeds collected from remnant plant populations was similar to the diversity of the restored populations. The studies showed that while genetic diversity showed some loss, 80 to 90 percent was represented, which was better than expected. (It's important to note that other studies found the remnant populations were low in genetic diversity due to loss of habitat.)
"Species diversity is improving over time. Ten years from now we may have a [better] picture," says Marr. "Once you have destroyed a habitat, it's very difficult to recreate it. TNC has done an extraordinary job. It's a complex system, and it is naive to think 'we can just fix it.'" She notes, however, that "even if a new wetland plant community is not exactly the same, it serves basically the same function in recycling the water."
Bob Brodman, professor of biology and environmental science at St. Joseph's College in Rensselaer, Indiana, is ecstatic about how quickly the amphibian and reptile populations have returned. "Not only are there numerous species, but also the number of individuals has greatly increased. In 1998 there were 14 populations of amphibians. In 2003 there were 172. I would have considered a 10 percent increase remarkable!" He notes that the northern leopard frog - which had been noted as a species of special concern - has shown the greatest population increase and reports finding an ornate box turtle, which is endangered in Indiana. "Only one, but that's better than none," he says.
The level of scholarship that is going into the Kankakee Sands project will have implications for prairie restoration everywhere. For example, Peggy Schultz, a research scientist at Indiana University, Bloomington, is studying the soils to determine whether it's possible to jump-start restoration by inoculating disturbed areas with other soil organisms from prairie remnants. "A prairie is like an upside-down forest," explains Schultz. Most of the biomass is below ground. To really get a community going we may have to add back the elements that tilling destroys. We are learning more every day."
The tactical changes at TNC have resulted in more than superficial improvements. The organization is working closely with government agencies and local parks and preserves. It also is encouraging easement agreements with individual landowners that guarantee perpetual "bridges" within large ecosystems.
Steven J. McCormick, TNC's president and CEO, says, "We cannot achieve success by just creating protected areas. We must embrace human activity. Conservation is a state of harmony between humans and the land, transcending the notion that there are 'protected areas' and, therefore, that everything else is unprotected."
Nan Booth Simpson is a landscape architect and writer in Wimberley, Texas.