Land conservation managers across the country are having to change how they do business, with climate change risks compounding existing threats to forests, wetlands, and coasts.
Consider an important nesting beach on Sawpit Island in the Nassau River near Jacksonville — a beach protected by the North Florida Land Trust. Sawpit is a state park because, among other things, its marshes support biodiversity and its beach is an important breeding habitat for diamondback terrapins. The turtles — with males reaching 5.5 inches and females 11 inches in length — rely on the island’s salt marshes for habitat. Like other sea turtles, they have “nesting fidelity,” meaning females return to the same beach year after year to lay eggs.
While other coastal beaches in Florida support about a dozen diamondback terrapin nests on average, the Sawpit Island spit of land is home to between 300 and 600 nests each spring.
But experts say rising seas and frequently damaging storms have reduced the island’s beach acreage by 75 percent over just the past decade: from eight acres to two acres. In 2013, 400 nests crowded Sawpit’s remaining beach acreage, a density that makes for easy forage for raccoons.
By backdating its sea level rise model from a time before the beach erosion happened, and with the sea level rise model predicting the erosion that actually has happened, says Marc Hudson, land protection director, the group is confident that sea level rise is playing a role in the loss of the beach.
Hudson wonders if his organization’s $2 million investment in preserving the remaining two acres of beach, located on a part of the island that’s owned by the State of Florida, remains a sound investment. The beach erosion, after all, continues, and researchers found not a single hatchling survived last year.
The group now is considering relocating the nests next season before they hatch. Hudson says the land trust typically would raise money to conserve this habitat, but repeated tide anomalies and storm inundations – all in the context of troubling predictions in climate models – show these last two acres of Sawpit Island beach gone by 2020.
“Even though it is critical habitat for the diamondback terrapin, [ycc-tweetable-text tweetable=”false”]I can’t make the case for land trust investment in land that won’t be there[/ycc-tweetable-text],” Hudson says.
Given the changes in his principal job of protecting cherished land, Hudson says he now views current and potential purchases through the lens of a changing climate. And he raises three questions:
- “Will it be lost to future inundation?” Bad investment.
- “Will nothing happen to it?” Then we are not changing our conservation planning decisions.
- “Will the ecosystems transition and make the land integral to coastal resiliency?” Good investment.
Those are the kinds of questions land conservation managers in other parts of the country increasingly are asking themselves as they adapt to current and projected impacts of climate change. While the North Florida Land Trust rethinks whether to conserve the remaining bit of Sawpit Island beach, other land trust managers also find themselves in new decision-making territory, purposely buying land projected to be under water as sea levels rise in order to, for instance, provide adequate food supplies or widen already-protected forest buffer zones along streams.
About 1,000 miles north of Sawpit Island, Scenic Hudson, a land trust in Poughkeepsie, New York, now is seeking to buy land upslope from the Hudson River, land likely to be under water in the future. The goal in this case involves providing plants and animals a migration path.
The river is tidal for almost 160 miles inland, all the way to Albany, says Sacha Spector, director of conservation science at Scenic Hudson.
“Everything we have worked on to conserve for the past 50 years is in the cross-hairs of sea-level rise along the river,” Spector says, pointing to the river’s freshwater tidal wetlands as important habitat.
“We are trying to prepare the estuary for a future with different conditions. [ycc-tweetable-text tweetable=”false”]We are trying to conserve areas that are critical and to prepare for the new normal[/ycc-tweetable-text].”
Krista Magaw, executive director of the Tecumseh Land Trust in Yellow Springs, Ohio, says she too understands the new-normal concept: conservation land her group has preserved primarily as agricultural land will be fundamentally changing over time.
Projected changes call for Magaw to be more strategic in where to invest, she says, and require looking beyond a handful of plants or animals or a single project to preserve. Rather, Magaw says that decisionmaking in the context of change requires taking a holistic view of an entire landscape and determining how it might provide increased resilience for natural systems.
“We protect a lot of agriculture land, and in some of it, land uses might need to appropriately need to change in time,” she says.
“We don’t try to be restrictive about the kinds of agriculture that is conserved. But some areas will need to come out of cultivation, and we now include wording in our easement to reflect future changes, such as expanding a riparian corridor that crosses farmland.”
Magaw says that improving resilience of natural ecosystems nowadays requires a much bigger focus on lands held under conservation easements: For instance, she says river forests can provide a buffer for water runoff.
“Climate change and temperature change compound with nutrient issues in Ohio to give us algal blooms,” she says. “With climate change, we are now looking toward a long period of time trying to protect large blocks of land in a watershed that has a central riparian corridor.”
Many land trusts increasingly use geographic information systems (GIS) mapping to inform their decisions. The mapping tool can help them model various scenarios in how water resources or land use changes will affect current conservation lands and also help them factor in future areas of concern.
The Trust for Public Land, for instance, started its climate conservation program five years ago and regularly overlays GIS models.
“The natural systems we are protecting will be different with climate change and we need to accommodate those shifts,” says Jad Daley, director of climate conservation at the Washington, D.C.-based nonprofit organization.
As just one example, GIS models showed that even with conservative estimates of climate change impacts, streams in Maine critical for breeding of Atlantic salmon are also climate-sensitive habitats. The Trust for Public Land was able to identify important Maine streams at higher elevations and less vulnerable to warming temperatures, and then widen a key Atlantic salmon refuge area by expanding the protected stream buffer that runs through 6,000 acres of working forest.
“As temperatures warm up in Maine, those streams will be critically important,” Daley says.
Another organization, the Land Trust Alliance, recently developed a new resource center to guide land trusts on how best to address risks posed by the changing climate. The center serves as a technical resource for land trusts and their supporters. The resource center contains 27 case studies so far. The group shares best practices and lessons-learned from its partners, ranging from local land trusts to the U.S. Fish & Wildlife Service.
Land Trust Alliance national director Erin Heskett says the challenges changing climate poses for long-term land conservation efforts are not only varied but also extremely complex. Heskett says the new resource center can help land trusts find information needed to better consider climate change in their ongoing land conservation work.