RAD Provides Options for Land Managers to Keep Pace as Climate Change Rapidly Transforms Wildlife Habitat
From the Spring 2022 Fish and Wildlife News

Alongside a paved road at Blackwater National Wildlife Refuge in Maryland, a large-yet-unassuming body of water sits just beyond a stretch of grassy marsh. From the adjacent observation deck, visitors can see birds roosting or watch the sun set and find nothing out of the ordinary. But for those with a trained eye, like refuge biologist Matt Whitbeck, the sight is alarming.

 Five thousand acres of tidal marsh once sat here, Whitbeck explains. Decades of sea level rise have drowned out the habitat, leaving behind only this quiet pool, christened Lake Blackwater. Knowing that, it’s harder for Whitbeck to appreciate the view.

Matt Whitbeck, Wildlife Biologist at Blackwater National Wildlife Refuge.

“’One of the penalties of an ecological education is that one lives alone in a world of wounds,’” he says, quoting early conservationist Aldo Leopold. Blackwater is a grim case study on the effects of climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's…

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. Since the refuge was established in the 1930s, rising waters have swallowed nearly half its historic wetland habitat, with more disappearing each year, and the encroaching salt water has left swaths of dead trees, called ghost forests, in its wake.

Salt marsh-dependent birds like the saltmarsh sparrow and black rail have all but vanished from the refuge as this valuable habitat disappears, and the threat of total population collapse looms large over these species.

It’s not just wildlife that are at risk. With the advent of more frequent and intense storms, losing these wetlands means losing the buffer that absorbs storm surge and prevents extreme flooding in coastal communities. Virtually all these wetlands could be under water by 2100.

Dramatic transformation is happening here and elsewhere. When it comes to tackling these challenges, the old ways of natural resource management are no longer sufficient. The speed and severity of climate change has altered the rules of the game. A new approach to managing through this change is needed, and we’re at the forefront.

Focusing on the Future

Wildlife managers traditionally focus on restoring habitats and wildlife populations to what they looked like in years prior, also known as “baseline conditions.” With climate change causing unprecedented and irreversible changes to the lands and waters, wildlife managers are focusing less on what things looked like in the past and more on what things will look like in the future.

Ghost forests at Blackwater National Wildlife Refuge are a result of the conversion of forests to wetlands as sea level rises. Photo by Kyle Derby/USGS

What exactly are these changes? Scientists are calling them ecological transformations. Ecological trans- formations occur when habitats and the communities of plants and animals that depend on them shift from one state to another — from estuary to freshwater wetland, salt marsh salt marsh
Salt marshes are found in tidal areas near the coast, where freshwater mixes with saltwater.

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to mangrove forest, or spruce forest to grassland.

“Traditional wildlife management relies on the principle that baseline conditions don’t change, but ecological transformation turns that principle on its head,” says Scott Covington, one of our senior ecologists. “Wildlife managers may reluctantly accept that baselines are changing, forcing them to shift management paradigms and seek alternative frameworks to address the issue.”

In response, we and other federal resource management agencies proposed the Resist-Accept-Direct, or RAD, framework, building upon decades of research for addressing wildlife management in the face of rapid change. Partners include the National Park Service, U.S. Geological Survey, Bureau of Land Management, U.S. Forest Service, and National Oceanic and Atmospheric Administration.

The framework provides three pathways for managers to consider when approaching conservation:

  • Resist represents traditional wildlife management. Actions are taken to counteract changes and restore habitats and populations to baseline conditions.
  • Accept is a conscious decision to take a hands-off approach to the transformation, allowing habitats to transition without intervention. This method accepts the loss of some species and habitats and the establishment of others.
  • Direct allows managers to incorporate future projections of the land and take actions that work alongside occurring transformations. The goal is to steer change in ways that continue to support biodiversity and provide ecosystem services.

Here is a sampling of how the RAD framework is being applied at Service- managed lands across the country:

Resist: Billy Frank Jr. Nisqually National Wildlife Refuge, Washington

A 19th century dike (first image) cut the estuary at Billy Frank Jr. Nisqually National Wildlife Refuge off from tidal flow, and it eventually turned the landscape into a freshwater wetland, but the removal of the dike in 2009 has helped return the landscape back to its baseline condition as an estuary rich with biodiversity. Photo by Glynnis Nakai

Billy Frank Jr. Nisqually National Wildlife Refuge is no stranger to ecological transformation. Before we obtained the land for the refuge in 1974, a five-mile- long dike had cut off the estuary from tidal inundation for a century. The dike was built to block salt water and tides so the area could be converted into rich farmland. Eventually, agricultural activity ceased, and rainwater collected in the former fields, transforming them into freshwater wetlands.

Over time, the wetlands were degraded by invasive reed canary grass and provided little habitat for wildlife. Refuge managers opted to resist these changes and restore the wetlands back to baseline condition, a high-functioning estuary. In 2009, they collaborated with Nisqually Indian Tribe and Ducks Unlimited to remove the dike.

Since natural tidal flow was restored, the estuary’s native vegetation has been slowly recovering and food resources have rebounded. The estuary now supports an abundance of wildlife, including the culturally significant and federally threatened Chinook salmon and a diversity of waterbirds.

For now, choosing to resist has created quality habitat for many species. Managers know the estuary will look very different in the coming decades with climate change, however.

The highest sea level rise projections show much of the tidal marsh habitat will transform to unvegetated mudflat or submerged habitat by 2100, while other parts of the estuary will creep farther inland. Recognizing the inevitable, managers have expanded the refuge’s approved boundary up-river and are keeping an eye on future land acquisition and habitat restoration that will help the refuge adapt to ongoing landscape changes.

Accept: Chassahowitzka National Wildlife Refuge, Florida

Warden Key and the Crystal River National Wildlife Refuge Complex the island is a part of have experienced such drastic effects of sea level rise that managers have sought new ways to protect wildlife. Seen here, the course of just 12 years. Photo by Joyce Kleen

Crystal River National Wildlife Refuge Complex, which consists of Crystal River, Chassahowitzka, Egmont, Passage Key, and Pinellas National Wildlife Refuges, has felt the effects of sea level rise acutely, as encroaching saltwater shifts freshwater ecosystems to brackish and brackish ones to salt water.

In the face of such strong forces, managers are left with few options besides accepting the change. Changes in salinity and, consequently, vegetation will force many wildlife species to leave the area, seeking better-suited habitats, while new, salt-tolerant plants attract other animals,

“On Chassahowitzka Refuge, there is not a lot that can be done to combat or compensate for sea level rise and the changes to the habitat,” says Joyce Kleen, a wildlife biologist at Crystal River Complex.

Mangroves are a group of trees and shrubs that grow in coastal zones. Many mangrove forests can be recognized by a dense tangle of roots giving the appearance of trees standing on stilts. These unique roots allow the trees to handle the daily rise and fall of tides. Photo by Jess Sutt/USFWS

Mangrove trees at the refuge exemplify this changing ecology. In the past, occasional freezes hindered their spread, and a lower sea level limited the area where the saltwater dwellers could place roots. Rising seas and an increasing average temperature are facilitating mangrove expansion eastward.

Kleen says the refuge has implemented several stopgap measures to keep these changes at bay and make the area habitable for native species. Yet, one refuge can do only so much to hold off the inevitable changes of a rising tide.

 Direct: Kenai National Wildlife Refuge, Alaska

Kenai National Wildlife Refuge sign in Alaska. Photo by Steve Hillebrand/USFWS

At Kenai National Wildlife Refuge, a warmer and drier climate has hindered the native Lutz spruce trees’ ability to produce sap, which defends against pests. The trees have grown more vulnerable to the spruce bark beetle, whose population has skyrocketed with warmer weather. With reduced defense and more bugs, trees across the peninsula’s southwest corner have died, making space for grass to quickly take over and turn the landscape, once a spruce forest, into a grassland.

Resisting and accepting this change were largely off the table at Kenai. Replanting a native spruce forest would only cause the destructive cycle to continue and allowing the newly established  grass to remain would leave the landscape a depleted monoculture with one grass species covering nearly 90% of the land.

Managers are contemplating a third option: Directing this change to foster a healthier, biodiverse area in drier, warmer conditions.

One option is to usher in the growth of another forest ecosystem by bringing in non-native plants, such as lodgepole pine. Many neighboring landowners have already done this, including the Ninilchik Native Association.

Another option, says John Morton, who served as supervisory biologist at Kenai for two decades, is to direct the flora already there.

“What you have now is a big grassland, without a grazer,” Morton says. Bison, he believes, are the foundational species the land needs. Through grazing and wallowing, they would introduce “patchiness” to the monocultured grassland, creating space for other plant species to grow and a more stable, richer environment. The approach would allow the landscape to operate as a resilient, self-reliant, steady-state system.

For now, at Kenai, refuge managers are researching options before committing to a direction — a choice that will have lasting impacts on the landscape and the species that call it home.

A New ‘Gold Standard’ for Conservation

At Blackwater, Matt Whitbeck remembers a time in his career when the “gold standard” of resource conservation was to restore land and water back to baseline conditions. The impacts of sea level rise on the refuge, however, have made that vision unattainable.

 Protecting habitat for the saltmarsh sparrow is one of the largest priorities for managers on many East Coast refuges under threat from sea level rise. Photo by USFWS

“Blackwater is changing, whether we like it or not,” Whitbeck says. “So, we’ve just got to acknowledge it, and work with it the best we can.”

Rather than try to preserve all the current tidal marsh, the refuge has identified areas that may be more resilient or are most valuable to the refuge’s focal species to resist the effects of sea level rise. Staff has also placed conservation protections where future tidal marsh is expected to occur and is working to direct upland habitats into productive salt marsh.

Our efforts at Blackwater and across the United States are works in progress, and RAD won’t address climate change overnight. But that’s the nature of this emerging approach: It’s a framework for building climate resilience that, as the late Rachel Carson described in her 1948 Service publication “Guarding Our Wildlife Resources,” “is dynamic, changing as conditions change, seeking always to become more effective.”

The RAD framework simplifies the decision process, Covington says, but it doesn’t absolve managers from making hard decisions. Climate change is a pervasive, global force demanding a new gold standard for resource management and stewardship, now and in the future. The challenge facing the Service, Morton suggests, is to help shape that future or be shaped by it.

“What’s different about climate change, as a driver and stressor on the system, is it knows no boundaries. You can’t draw your refuge boundary and hold it back,” Morton says. “It’s coming across the landscape, and that’s the way it’s going to happen. So, we may as well take control of it. We may as well be responsible for the outcomes.” 

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