Grand Canyon takes steps to oust a wandering herd of non-native beasts
It’s been more than a decade since a trophy bison herd started making a mess on Grand Canyon National Park’s North Rim, and finally, officials are taking action. Grand Canyon National Park, Kaibab National Forest and the Arizona Game and Fish Department have recently launched a years-long process to decide how to stop the wayward animals from trampling the North Rim’s sensitive soils and vegetation – and, perhaps, entice them to return to the lower-elevation hunting grounds where they (sort of) belong.
The bison herd, about 300 strong, began in the early 1900s with an ill-fated attempt by Arizona game managers to cross bison with cattle to create hardier beef cows. The experiment didn’t succeed on the cow side, but it did create generations of animals that look and act like bison but harbor cattle genes. Dubbed “beefalo” or “cattelo,” the mostly-buffalo descendants have continued to populate state game herds, including one at House Rock Valley, an isolated landscape of mostly piñon-juniper, red earth and enormous views just north and east of the Grand Canyon’s North Rim. There, they starred in a highly successful annual buffalo hunt hosted by Arizona Game and Fish.
But by the tail end of the 20th Century, the House Rock bison did what most of their genes told them to: they wandered, in search of better fortunes. On the North Rim, they found what must have seemed like paradise: Cool pine forests where guns don’t shoot, wide tanks with muddy shores, and vast meadows full of tender greens. The bison haven’t looked back much. And the herd has thrived, roughly tripling in size over the past decade.
Grand Canyon biologists first became concerned in 2001 and 2002, when they noticed that the bison were hammering meadows near the Grand Canyon entrance station on Highway 67. There was also damage to some archeological sites, likely from when the massive creatures rubbed up against them.
But initial attempts to track down and corral the animals disabused park officials of any notion that the bison could be herded like cows. One effort, in 2003, was especially eye-opening. For four days, park biologists camped on the rim and formed two search parties, early each morning, to try to locate the herd in the North Rim’s vast ponderosa pine forests. Their mission: to use a tranquilizer gun to stun just one animal, so they could get a blood sample to test for confirmation of the animals’ hybrid genome.
If they could show that, they reasoned, they’d be justified in taking any measures necessary to oust the non-native animals from the park. The National Park Service’s mission, they decided at the time, only directed it to protect native wildlife.
The biologists saw no sign of the bison until the last day, when one of the teams spent hours painstakingly stalking part of the herd to a ridge. Finally, when a National Park Service veterinarian got within about 40 feet of a bull – close enough to hear it snort and paw at the ground – she reached into her bag to pull out the loaded tranquilizer gun. Despite every effort to make the move slowly and silently, she let the gun click softly against another object in her pack. The animals scattered so cleanly and quickly, they might as well have been the shadows of the trees themselves.
It was likely the closest anybody’s been since.
All was not lost, however, because one of the animals left a tuft of fur on a branch that James Derr, of Texas A&M University, used to confirm the herd’s hybrid origins.
At the time, the major land- and game-management agencies disagreed on how to handle the bison. The Kaibab National Forest took a hands-off approach, and the Arizona Game and Fish Department didn’t even agree the bison were a problem in the first place.
“They’re free-roaming wildlife from the state of Arizona’s perspective and have been since 1926 or so, when the state acquired the herd,” Ron Sieg, the former Flagstaff-based regional supervisor for Arizona Game and Fish, told the Four Corners Free Press in 2010. “Under our state laws we have to treat them as we would other wildlife in the state.”
The buffalo hunting tag is the most expensive in the state, costing about $1,000 for residents for a bull, and up to four times that much for out-of-staters. And the wild behavior that stymied the efforts of the Park Service biologists makes the bison especially coveted among hunters.
But even as Sieg took his stand, change was under way. Tom Sisk, an environmental- science professor at Northern Arizona University, brought master’s student Evan Reimondo on board to make a study of the buffalo herd’s impacts on the North Rim. Together, the two scientists began calling meetings with representatives from Grand Canyon National Park, Kaibab National Forest, and Game and Fish.
Reimondo documented the herd’s significant impacts on park resources, especially the soils and vegetation in its high-altitude meadows. He has since graduated with his master’s degree. And, in a dramatic shift, all three agencies are now on the same page.
Martha Hahn, Grand Canyon’s chief of science and resource management, said Reimondo’s research was key in opening people’s eyes to the herd’s impacts on resources – both in the park and across the invisible border with the Kaibab National Forest. Grand Canyon biologists have let go of a previous campaign to prove the animals are hybrids.
“No matter what we call them, they’re causing impacts to critical park resources, and we have to manage that,” Hahn said. She added that the animals also pose hazards for visitors.
“They’re very leery. When people pull off the road … it isn’t like Yellowstone. If you get out of your car, they scatter and leave into the forest. The problem is at night. We’ve had a lot of car-bison collisions. They come out at night, and you can’t see them.”
The Kaibab, in a revision to its forest management plan released in February, directed that “the bison herd should be managed so it is concentrated within the House Rock Wildlife Management Area, and … active management should be used to minimize impacts from bison to sensitive resources,” especially vegetation and springs. These days, Arizona Game and Fish agrees – partly because the bison have gone missing during the formerly profitable annual hunts.
Calling themselves the Tri-Agency Group, the three agencies went public last month with an environmental impact statement to assess ways to manage the bison. The effort will take several years. At this point, Hahn said, the process is very much open to input – and a lot remains to be seen.
“We could come up with tools to trigger movement out of the park, so that they’re out on the forest, and there may be a special hunt,” Hahn speculated. “Or Game and Fish may determine that they want to establish a herd somewhere else in the state and move them, or come to an agreement with an interested tribe.”
She said some experimentation is already under way: Game and Fish is studying how hunting pressure is keeping the animals on the North Rim, and park biologists are experimenting with new techniques for moving the herd around. One promising new tool is “cake,” a type of bait in pellet form that the bison seem to love.
In a separate but parallel process, the Department of the Interior, parent agency of the National Park Service and the Bureau of Land Management, has been working on a national Bison Conservation Initiative. That effort recognizes that bison require large territories, and seeks to coordinate habitats across Interior’s public lands. Hahn said it’s possible, even though bison in the Grand Canyon region are considered less genetically pure than others in the country, that the Grand Canyon-area efforts could figure into the national-management scheme.
Work done through the University of Arizona has suggested that the House Rock Herd’s current range would have been at the southern edge of historic bison country.
“If bison were present in the Southwest, as the evidence suggests, they likely entered the region only occasionally as small, dispersed herds,” concluded Donelle Huffer in a 2013 master’s thesis.
“Those that came through this area were pretty much lone, single types or a string of six or eight, just moving through,” Hahn said. “That will play big in terms of how we consider the impacts and the carrying capacity in the park, no matter what their genes are.”
The first in-person public meetings were held April 28-30 in Kanab, Flagstaff and Phoenix. Two online public meetings are coming up, at 5 p.m. Mountain time on May 6 and 7 p.m. Mountain time on May 7. To reserve a “webinar seat” at the first meeting, visit https://www1.gotomeeting.com/register/ 272848057. For the May 7 meeting, use the site https://www1.gotomeeting.com/ register/484241881.
The main Bison EIS web site, at http://parkplanning.nps.gov/grca_bison_eis, also provides a comment form.