1 00:00:02,033 --> 00:00:04,300 JUDY WOODRUFF: Here in the United States, the national parks belong to all of us. 2 00:00:04,300 --> 00:00:09,133 But as Tyler Fingert from the Cronkite School of Journalism at Arizona State University 3 00:00:09,133 --> 00:00:13,133 reports, that shared treasure is at risk of being chipped away. 4 00:00:13,133 --> 00:00:18,000 TYLER FINGERT: Across the desert landscape, their silhouette is unmistakable. 5 00:00:18,000 --> 00:00:23,000 At Saguaro National Park near Tucson, cacti are the main attraction for hikers like Jean 6 00:00:24,066 --> 00:00:26,166 Gascho. 7 00:00:26,166 --> 00:00:28,933 JEAN GASCHO, Hiker: You feel like you're so much a part of the desert and just surrounded 8 00:00:28,933 --> 00:00:31,800 by these beautiful cactuses. 9 00:00:31,800 --> 00:00:35,400 TYLER FINGERT: But the park's namesake cactus is facing a threat from thieves. 10 00:00:35,400 --> 00:00:38,366 KEVIN DAHL, National Parks Conservation Association: It's ironic that we set aside great places 11 00:00:38,366 --> 00:00:42,766 like our Saguaro National Park, and people think that they can just come take the iconic 12 00:00:42,766 --> 00:00:44,800 cactus for which the park is named. 13 00:00:44,800 --> 00:00:48,933 TYLER FINGERT: Kevin Dahl works with the National Parks Conservation Association. 14 00:00:48,933 --> 00:00:51,900 He says being a cactus thief can be lucrative. 15 00:00:51,900 --> 00:00:55,066 Each one can fetch $100 or more per foot. 16 00:00:55,066 --> 00:00:59,933 KEVIN DAHL: It's absolute robbery, and it's absolute criminal activity. 17 00:00:59,933 --> 00:01:02,100 And it's for profit. 18 00:01:02,100 --> 00:01:06,466 A mature saguaro in a landscape adds something to the value of the home or the business that's 19 00:01:07,200 --> 00:01:09,266 for sale or rent. 20 00:01:09,266 --> 00:01:11,300 TYLER FINGERT: Across the country, other parks are facing a similar threat. 21 00:01:11,300 --> 00:01:16,133 Last year, Death Valley National Park says some visitors walked off with fossil footprints. 22 00:01:18,133 --> 00:01:20,200 At Joshua Tree National Park, people have stolen artifacts from old mines. 23 00:01:20,200 --> 00:01:22,233 BILL PARKER, Petrified Forest National Park: Some parks deal with people taking rocks. 24 00:01:22,233 --> 00:01:26,033 Some parks deal with people taking plants and animals. 25 00:01:26,033 --> 00:01:29,733 Places like Mount Rushmore, people take the chips that were created when they created 26 00:01:29,733 --> 00:01:31,833 the sculptures. 27 00:01:31,833 --> 00:01:34,733 TYLER FINGERT: Bill Parker leads the Natural and Cultural Resources Team at Petrified Forest 28 00:01:34,733 --> 00:01:36,200 National Park. 29 00:01:36,200 --> 00:01:39,600 Here, he says, visitors take small pieces of petrified wood. 30 00:01:39,600 --> 00:01:44,566 BILL PARKER: Some people do still take wood, and we catch them and give them tickets. 31 00:01:44,566 --> 00:01:48,100 But whole areas aren't being stripped clean, as was thought in the past. 32 00:01:48,100 --> 00:01:53,066 TYLER FINGERT: The park turned to photography to test the theory, taking century-old photographs 33 00:01:54,733 --> 00:01:57,066 and comparing them to recent photos taken at the same location. 34 00:01:57,066 --> 00:02:01,633 And the results, says Parker, if you look at photos from today, most of the artifacts 35 00:02:01,633 --> 00:02:03,633 are still intact. 36 00:02:03,633 --> 00:02:06,833 BILL PARKER: It's a souvenir that people want, but one thing the photography project has 37 00:02:06,833 --> 00:02:08,933 showed us is that most people do the right thing. 38 00:02:08,933 --> 00:02:13,300 TYLER FINGERT: Some people have even returned stolen wood, and it ends up here, often referred 39 00:02:13,300 --> 00:02:15,300 to as the conscience pile. 40 00:02:15,300 --> 00:02:19,533 Back in Saguaro National Park, to help make sure theft doesn't happen, the National Park 41 00:02:19,533 --> 00:02:24,533 Service has turned to technology, putting tiny passive trackers in some of their cacti, 42 00:02:26,000 --> 00:02:28,433 allowing them to identify ones stolen from the park. 43 00:02:28,433 --> 00:02:33,433 Of their roughly 1.9 million saguaro cacti, only 1,000 of them are tagged, the ones close 44 00:02:34,900 --> 00:02:38,433 to roads and the smaller cacti, those most likely to be stolen. 45 00:02:38,433 --> 00:02:43,433 The trackers, which are similar to pet microchips, don't actively broadcast a signal, so if a 46 00:02:43,433 --> 00:02:48,133 cactus goes missing, Ray O'Neil, Saguaro National Park's chief ranger, says the only way to 47 00:02:48,133 --> 00:02:52,733 know if it's from the park is to scan it using a reader, making the trackers more symbol 48 00:02:52,733 --> 00:02:55,266 than substance. 49 00:02:55,266 --> 00:02:57,433 RAY O'NEIL, Chief Ranger, Saguaro National Park: Our biggest hope is that it's a deterrent, 50 00:02:57,433 --> 00:03:00,366 that people recognize that if they steal cacti from Saguaro National Park, that there's a 51 00:03:00,366 --> 00:03:03,400 chance that we're going to be able to identify that cactus came from the park. 52 00:03:03,400 --> 00:03:07,800 TYLER FINGERT: While technology is helping to track natural resources, education is still 53 00:03:07,800 --> 00:03:10,800 a huge part of keeping parks pristine. 54 00:03:10,800 --> 00:03:15,133 And Kevin Dahl wants to make sure that visitors understand the national parks are saved by 55 00:03:15,133 --> 00:03:17,133 the people for the people. 56 00:03:17,133 --> 00:03:21,333 KEVIN DAHL: It's a selfish thing when someone does an act of vandalism or steal something 57 00:03:21,333 --> 00:03:22,800 from a national park. 58 00:03:22,800 --> 00:03:26,333 And it's selfish and it's an act against the American public. 59 00:03:26,333 --> 00:03:31,333 TYLER FINGERT: Pieces of American history being taken from some of America's most treasured 60 00:03:31,800 --> 00:03:33,833 land. 61 00:03:33,833 --> 00:03:36,333 For the "PBS NewsHour," I'm Tyler Fingert at Saguaro National Park in Arizona.