CONCORD MONITOR (New Hampshire) 16 June 03 For wildlife, re-created wetlands not the same - Studies cast doubt on replacement projects (Amy McConnell)
Spring came and brought with it the start of nesting season, and the wood turtle emerged from the sandy stream where she had spent the winter, tucked beneath an overhanging bank or wedged beneath a fallen pine tree. She crawled, eating slugs along the way, up through wetland thickets of ferns and silky dogwood trees toward the open sand banks where she would dig a nest for her leathery eggs.
She paused beneath the shady cover of an ironwood tree, where naturalist David Carroll discovered her a couple of weeks ago, her brown shell sleek against the fallen pine needles.
The turtle, he said, belonged to a colony living in and along the river, part of a complex system of wetlands around Warner. Many of those turtles, Carroll said as he gently picked up the female to examine the identifying markings of her mottled underbelly, begin breeding at about age 20 and will live in the same place for 50 years or more if their habitat is left undisturbed.
"She's lived out here for many years," Carroll said, as the turtle blinked once and drew her head back between her orange front legs. "She's an important breeder."
The turtles, which are sensitive to disturbance and require large unbroken stretches of wetland areas and nearby upland forest to thrive, are good indicators of the health of wetland ecosystems, Carroll said. Wetlands make up about 10 percent of New Hampshire's landscape, but are home to an outsized proportion of its wildlife. More than half the state's rare plant and animal species are found in wetlands, more than 90 percent of its animals regularly use wetlands, and more than 40 percent of its wildlife prefers wetlands over other habitats, according to environmental officials.
In addition to supporting abundant wildlife, healthy wetlands help the human population as well: They store excess rainfall and snowmelt, letting precipitation slowly replenish groundwater and drinking water supplies rather than quickly running off the surface to flood homes and businesses.
But the number of undisturbed swamps and marshes, bogs and ephemeral springtime pools is shrinking. In Warner, tires had left fresh, muddy tracks recently in the few dozen feet of open space the female wood turtles were crossing to reach their nesting sites. Similar colonies - along with the populations of fairy shrimp, salamanders, songbirds, otters and other development-sensitive species - lose about 100 acres of wetland habitat a year to residential development and road-building in New Hampshire, according to the Environmental Protection Agency.
New rules being proposed by the state would require developers to replace more of those destroyed wetlands: For every acre of wetlands lost, developers would have to build 1.5 acres of new wetlands. Critics, however, say the rule seems to shift the state's emphasis away from protecting wetlands and toward replacing them with what are often weak substitutes, giving developers a freer hand in the process.
Created wetlands rarely, if ever, replace what was lost, according to wetlands scientists and recent studies examining the success of such mitigation, or replacement, projects in New Hampshire and the rest of New England.
In a draft report released earlier this year by the U.S. Army Corps of Engineers, researchers found that 67 percent of the 60 wetlands replacement projects - including 13 in New Hampshire - met the requirements of their permits. But just 17 percent actually worked like the originals they were designed to replace, according to the study.
While nearly all of the 324 acres that were supposed to have been re-created had been built, the study found that the re-created wetlands were often totally different ecosystems from the originals. More than 50 percent of the destroyed areas were complex, forested wetlands of red maple and other trees, but most developers instead had built simpler, cheaper ecosystems such as shrub wetlands or open ponds surrounded by a thin fringe of wetlands plants.
As a result, the new wetlands covered about the same acreage as the original area but failed to serve the same purposes, researchers found.
"The general replacement of forested wetlands with open water (ponds) and emergent systems has resulted in considerable loss of function, particularly for wildlife habitat and water quality," the report states.
A 1997 study performed by the Audubon Society of New Hampshire at the request of the EPA found that New Hampshire environmental regulators often did not require any mitigation at all, even for many of the projects with large impacts. Of the 401 permits the state issued in 1995, just 12 required developers to replace the wetlands they destroyed, according to the report.
The study, in looking at the 70 construction sites given wetlands permits between 1990 and 1995, found that more than 40 percent of re-created wetlands got their water supply at least partly from storm water drainage or surface water runoff - not from groundwater, which feeds most natural wetlands. As a result, many of those re-created wetlands had poor water quality because of algae blooms, sediment, trash, or an oily sheen from oil and gas runoff from nearby parking lots, according to the report. (Researchers made no water-quality observations on the remaining 18 projects using storm- or surface-water runoff because those wetlands had no water, the study notes.)
If developers are allowed to base their projects on simply creating the same number of acres they destroy, "we could end up with lots of holes in the ground next to roads and parking lots which help to create a fiction of no-net-loss," according to Mark Kern, a wetlands biologist with the EPA's New England office.
Isolated pockets of artificial wetlands - inside the cloverleaf of an interstate exchange, or next to a mall, for instance - may serve a wetlands function such as controlling runoff, but can't replicate original habitat because animals are easily hit by cars or eaten by predators when crossing roads and parking lots, he said.
Such projects, however, make up the majority of re-created wetlands, Kern said.
"What often happens is that what we fill in the middle of the woods we attempt to recreate next to a parking lot," he said. "What we're seeing is that most developers will do what's easy and cheap."
Some developers, and many state agencies such as the state Department of Transportation, have realized the flaws in that kind of project, according to former environmental services commissioner Dana Bisbee. As a result, more are trying to re-create lost wetlands as large parcels connected to intact areas, he said.
For example, projects like those designed to compensate for wetlands lost to access roads and parking lots at the New Hampshire International Speedway in Loudon, and to a wider road on Route 101 outside Hampton, function much as the originals wetlands did, according to Bisbee.
"It is not as good as leaving the wetlands area untouched, but when it's necessary, mitigation can be effective," he said.
Such success stories, however, come at a price. The EPA estimates that successful wetland mitigation can cost $100,000 per acre - or about $100 million for the Route 101 replacement project.
Spending that kind of money on a mitigation project probably is the exception, not the rule, among developers, according to Peter Kinner, a marine biologist and vice president of Normandeau Associates, an environmental consulting group that designed the mitigation package for the Route 101 expansion. It depends on who's proposing the construction, he said.
"Major projects like those promulgated by state agencies or major industries where there are deep pockets, it's probably the rule," Kinner said. "Does that happen with a housing lot developer? Probably not."
Even with enough money and a willingness to spend it, there are limitations to re-creating ecosystems that have been evolving since the glaciers receded 15,000 years ago. It's difficult to reproduce a red maple forest quickly, for instance, and that can mean few other wetlands-sensitive species come to live there within the typical five-year monitoring period, Kinner said.
"You start to see some things coming back, but in the complex habitats where key species are slow to establish, the time scale is going to be a lot longer," Kinner said. "Maybe history will show that we need to concentrate on other kinds of habitats . . . like the ones that are simpler to do."
To Carroll, whose book Swampwalker's Journal chronicles the life of wetlands ecosystems in intimate detail, the difficulty of re-creating complex habitats doesn't mean people should scale back such projects; it means they should avoid the development that requires them. Off another side road in Warner, the members of a colony of 125 spotted turtles feed and mate among the pools and tussocks and flag iris of a shrub wetland, but the females must crawl into the drier upland forest to lay their eggs and the turtles winter over in yet another location.
Without all those parts of the landscape left intact, the life cycle of the turtles - and many wetlands animals like them - is cut short, he said.
"They need this whole landscape for that to play out, and they need to shift with the changes in the landscape," Carroll said. "We say we can dig this hole and fill it with water and throw some turtles in - it doesn't replace what was lost."
For wildlife, re-created wetlands not the same

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