Conservation Mismatch
New research shows that some of the least-protected regions in the United States are home to some of the most vulnerable species.
The United States has a long and admirable history of protecting its natural heritage, from the creation of Yellowstone National Park in 1872 to President Obama’s February designation of the Browns Canyon National Monument in Colorado. Its national parks, marine protected areas, and natural reserves stretch from sea to shining sea. And yet many of the most biologically rich areas in the country remain unprotected.
A study published this week in the Proceedings of the National Academy of Sciences shows that the largest swaths of protected wilderness in the Lower 48 are in the interior West. Meanwhile, the highest density of vulnerable species can be found in the Southeast, Texas, and California.
“These priority areas are a relatively small part of the country,” says lead author Clinton N. Jenkins, founder of Biodiversity Mapping, a global GIS initiative that originated in North Carolina, and visiting professor at the Institute for Ecological Research in Brazil. “Pumping up our conservation investment there could make a big difference.”
Overall, less than 8 percent of the Lower 48 is categorized as protected by the International Union for Conservation of Nature (compared with a global average of 10.3 percent). Much of what is protected came into existence to safeguard beautiful landscapes, such as the Grand Canyon, rather than biodiversity.
“Like most other nations on earth, we protect the cold and the dry,” says Stuart Pimm, conservation chair at Duke University and a coauthor of the paper. “We’ve set aside . . . huge areas of wilderness that essentially nobody else wants.” (He adds that he loves the western national parks and is not belittling their value.)
Before the paper was published, Pimm reached out to his friend, Pulitzer Prize-winning biologist E.O. Wilson, who agreed to review it. “Ed is very, very enthusiastic about this paper,” Pimm says. “He’s the father of biodiversity, the person who made that term famous.”
The study highlights total species richness in the Lower 48, pointing out that bird biodiversity is highest along the coasts; mammal biodiversity is highest in the West; reptile biodiversity is highest across the South; and amphibian, freshwater fish, and tree biodiversity are highest in the Southeast. Since widely distributed species normally need less management, the authors focused only on endemics (those that live entirely within the Lower 48 and that generally have small ranges) while measuring land conservation priorities.
By analyzing the ranges of more than 1,200 endemic species and the proportion of their ranges that’s protected, the authors found that the vast majority of vulnerable animals and trees appear in only a few places: the Blue Ridge Mountains and rivers of the Southeast; the Sierra Nevada, Klamath, and coastal mountain ranges of California; the Channel Islands of California; south-central Texas; the Florida panhandle; and the Florida Keys.
Birds are doing fairly well compared with other taxa, thanks to their mobility and the help of the avian conservation movement. Still, many of the 15 endemic bird species in the Lower 48 are at risk, including the Lesser Prairie-Chicken, Gunnison Sage-Grouse, Red-cockaded Woodpecker, and Florida Scrub-Jay.
The situation is perhaps most dire in the Southeast, which has the most mussel and crayfish diversity of anywhere on earth and more snail diversity than anywhere but Southeast Asia, says Paul D. Johnson, program supervisor at the Alabama Aquatic Biodiversity Center, who was not involved in the study. Unfortunately, some 70 species of snails and mussels, plus two fishes and a crayfish, have already gone extinct in the region.
Today, many more Southeastern species stand on the brink. “We know where these really high-diversity river basins are—there are about 10 of them.” Johnson says. “These are the last places that those species occur.”
He points out that Alabama has more animals listed under the Endangered Species Act than any other state. Yet it receives scant federal funds and houses several unprotected waterways.
Above the state level, Jenkins recommends promoting conservation easements and designating more national forest land as wilderness. Ultimately, though, there is no one-size-fits-all solution for these vulnerable species.
“Everybody loses if these species go extinct,” Jenkins says. “Collectively, society should contribute to making sure they’re there.”