Warming Trends Alter Conservation

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At the Blackwater National Wildlife Refuge on Maryland’s Eastern Shore, sea-level rise threatens to drown the brackish marsh on which migrating shorebirds depend.

In Northern California, the shrinking snowpack has reduced stream flows that sustain the delta smelt, a federally threatened fish species.

Higher summer temperatures in northern Minnesota have depressed the birthrates of the area’s once-populous moose, and just 20 inhabit the Agassiz National Wildlife Refuge that was designed in part to shelter them.

As climate change begins to transform the environment in the United States and overseas, policymakers and environmentalists are realizing that the old paradigm of setting aside tracts of land or sea to preserve species that might otherwise disappear is no longer sufficient. It was an idea that worked in 1872, when one of the reasons cited for establishing Yellowstone National Park was to help preserve the few remaining buffalo.

But as temperatures rise and animals and even plants migrate to more hospitable habitats, fixed boundaries set years ago no longer provide the protection some species need. Experts are exploring new strategies, focusing on such steps as protecting migration corridors, collecting and transplanting seeds, making sanctuary boundaries flexible and managing forests in novel ways.

“We have focused on one single principle: You protect the place where the animals live,” said Lawrence A. Selzer, president and chief executive of the Conservation Fund. “That’s fine as long as everything’s static.”

Now, with rapid change, federal agencies, including the Fish and Wildlife Service, the Forest Service and the National Oceanic and Atmospheric Administration are beginning to draft management policies that take global warming into account.

NOAA Assistant Administrator Richard W. Spinrad advocates creation of a national climate service to give agencies across the federal government better access to scientific projections so they can anticipate and plan for eventualities such as extended droughts and changes in water flows.

“Many people felt this was a marginal issue to their particular missions, and now they’re realizing it’s not,” Spinrad said, adding that the new thinking reflects “the accelerated pace in which we are seeing the direct impact of climate change on the environment. . . . The need for a national climate service is as strong now as the need for a National Weather Bureau was 120 years ago.”

Coming up with concrete strategies for coping with warming trends is a tougher challenge. Anne Morkill, who manages the Key Deer National Wildlife Refuge north of Key West, Fla., said her staff is working with the Nature Conservancy and Florida International University on models of sea-level rise to determine to what extent saltwater intrusion will erode the rocky pine habitat that supports the Key deer and other species. The refuge was created in 1957 to protect the rare subspecies of white-tailed deer, which became geographically isolated 20,000 years ago; after dwindling to a low of 25, the population now stands at 500 to 700.

Refuge managers could try to relocate the deer, Morkill said, but “a Key deer outside the Florida Keys is no longer a Key deer.” Moreover, she said, officials need to ask themselves: “How much resources should we use today to preserve a habitat that may disappear in 50 years?”