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We're going to talk next about some numbers that could dismay environmental activists. The numbers suggest that we are less in touch with nature. Since the late 1980s, the percentage of Americans who visit wild places has plummeted, and a new study says that number may still be dropping. NPR's John Nielsen has more.
JOHN NIELSEN: Anyone who's ever tried to book a room near Yellowstone National Park in August knows that natural places can get very crowded. But biologist Oliver Pergams says those crowds have been hiding an important trend: Every year, he says, a smaller percentage of Americans have been fishing, camping or engaging in other nature-based activities.
Professor OLIVER PERGAMS (Biological Sciences, University of Illinois at Chicago): Most of them have been declining since the '80s at about a little over a percent a year, and most of them have lost about 18 to 25 percent from their peaks.
NIELSEN: Pergams teaches at the University of Illinois at Chicago. For several years now, he's been collecting outdoor head counts kept not only by national parks, but also by state and local parks, the U.S. Forest Service, the federal Bureau of Land Management and commercial polling firms, for starters.
Prof. PERGAMS: We've got data for hunting licenses, fishing licenses, three different data sources for camping and backpacking and hiking.
NIELSEN: Pergams says the data sets show that a few outdoor activities have managed to remain popular. For example, one in 10 Americans has gone out hunting every year for the last several decades. But Pergams says that is the exception to the rule. He says almost all the other outdoor activities, like visiting parks, have headed sharply downward since the early 1990s.
Prof. PERGAMS: It ends up, all these things were very, very similar. The peaks in visitation or the peaks in use were around the same time. The losses since the peaks have been about the same percentage. They're all acting pretty much in the same way.
NIELSEN: Pergams thinks environmentalists should be concerned by this broad change, at the very least. He says that's true in part because people who don't visit natural places might not fight so hard to protect them.
Prof. PERGAMS: It's perfectly possible to be in favor of something but not necessarily to support it fully. You know, you have polling on presidential issues, for instance. Though everybody says they support the environment, you know, when you come down to it, almost all the other issues rank ahead of it.
NIELSEN: The study appears in the Proceedings of the National Academy of Sciences. In it, Pergams speculates that these declines could have a wide variety of causes, ranging from rising gas prices to increases in the amount of time spent in front of video games and TV screens.
Environmental historians, like Mark Barrow of Virginia Tech, think the changes described in this paper are potentially historic. Barrow says it's worth remembering that Americans have changed their attitudes toward nature many times over the centuries. It has been seen in turns as evil, something to be tamed, a source of untold wealth, and as what Barrows calls a romantic playground.
Professor MARK BARROW (History, Virginia Tech University): This place where you could go and experience wilderness and feel like you were connecting with something that was primal and part of who you were as a culture.
NIELSEN: But Barrow says this new study makes him wonder whether a new era may be dawning, one in which the wild is a place best seen at zoos or on plasma screen TVs.
Prof. BARROW: The era of mediated nature? I don't know if we have a title yet for it, but it clearly seems to be the case that we seem to not need to experience the natural world in the ways that we did previously.
NIELSEN: The new study says Americans might not be the only people changing in this fashion. Numbers from Japan show similar declines in things like park visits. John Nielsen, NPR News, Washington.