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Bear signs in Big Bend

Hunger drove Candy from the mountains of northern Mexico, spurred her across huge stretches of uncharitable desert, compelled her to swim the Rio Grande, and pushed her across more rugged ground before she finally reached the promised land of the Chisos Basin in the Big Bend of Texas.

 

One day in the 1980s, she did what no other female Mexican black bear had done in 50 years. She made the Big Bend her home.

 

Eventually, fanciful humans named her Candy, although scientifically, she’s known as Bear #7.

“She’s the matriarch,” says Dave Onorato, a doctoral student from Oklahoma State University who has spent the last three years studying the bears in Big Bend. It’s his day off and his father’s come to visit, but Onorato’s taking the time to explain his work and show me one of his bear traps. His enthusiasm for the bears emerges in his willingness to venture forth on a freezing morning just to talk about these animals. We take his truck to a trap site, and as he listens for signals from collared bears in the park, he talks about Bear #7. “She came here in about 1984 and started to reproduce in 1988,” he says, which was an important event that helped establish the area as bear habitat. Onorato’s work with the bears indicates that Bear #7 contributed her genes to much of the local population. Although scientists are expected to be dry and detached in their work, he has named his bears: Candy, Little Mama, Trixi, Vixen. Today, we are listening for Hershey’s signal. He is a small yearling male, and at 40 pounds he is about 20 pounds underweight for this time of year.

 

Before the advent of Bear #7, the conspicuous absence of black bears in west Texas engraved itself as a permanent fact in the minds of residents and visitors alike. Bear #7 and the comeback bears that followed surprised west Texans and the National Park Service. Many of us Texans had learned that in Big Bend, bears had gone the way of the wolf. When a friend of mine, known for his tall tales, claimed to have seen a black bear in Big Bend National Park in 1988, I secretly dismissed his story as an exaggerated javelina sighting. But these days, a yellow sign with a bear silhouette warns of a new presence in the park, unmistakable evidence that the bears are indeed back.

 

Raymond Skiles, park wildlife biologist, says that as the comeback bears have changed attitudes about living in the Big Bend area, the people in the area have changed their attitudes about the bears. “We’ve seen a different feeling of more welcome from society since the bears came back,” he says, “especially compared to what we find in the records from the turn of the century.” In the early 1900s, black bears disappeared from the area, largely because people killed them or moved into their territories (see sidebar). The bears retreated to Mexico and stayed there for decades before beginning their tentative return to Texas.

 

It’s a different Texas from the one they left behind decades ago. “There’s a lot of optimism as the bears recolonize west Texas,” says Skiles. “Now we would like to live with them. They enrich our lives, and landowners are willing to consider strategies for managing livestock with bears.” What if bears do become a problem? “Landowners will always have to have some options for dealing with individuals that aren’t compatible,” he says, “but for all parties concerned, we have the attitude that we can get along.”

 

The bears’ preferred habitat might make that truce a little easier to honor. Their best food sources lie in the park, and the population centers within the park’s boundaries. But how long the bears will stay put in Big Bend is another story.

 

Onorato tells the story as I follow him to the bear trap on an unseasonably frigid October morning in Big Bend. Later in the day, a winter storm will lock the desert in ice, an unexpected event a week after highs in the area hit 100. “This year, they’ve begun a fall migration,” Onorato says about the bears as we make our way through low-hanging tree limbs and lingering mist. “They’re taking long fall journeys starting around mid-August, and they’re expected to return in mid-November to the natal site. The question is whether or not they’ll come back.” He hopes they will but reports that already four collared bears have died in Mexico where bears are protected in some areas, but not in others. Black bears are protected in Texas.

 

The fall migration caused the population of bears in the Big Bend area to shift in 2000. Estimates early in the year put the number of bears at about 25, but by November, that estimate dropped to 10 or 15. Females are trekking back to northern Mexico, covering the kind of acreage usually reserved for the more enterprising males. “One female has migrated 100 kilometers (60 miles),” Onorato says, “and that’s very far for a female. Usually, 15 to 20 kilometers is a long way for them to go.”

 

Why are the bears leaving? Food. Drought and a little caterpillar may have conspired to drive the bears southward. For two consecutive years, the leaf oakworm caterpillar has decimated oaks in key habitat, depriving the bears of acorns, a preferred food. Drought decreased other forage, including the juniper and madrone berries the bears particularly target. As we hike to the bear trap just off the Basin road, Onorato points out the madrones. The deep red bark stands out against green leaves, but it’s true -- no berries are in sight.

 

“In the fall, it’s important for the bears to put on a lot of weight,” Skiles says. “When acorns are low, they target madrone trees. It’s clear that more wooded, wet areas are very important.” The lingering drought has deprived the bears of this important habitat, possibly sending them south.

 

Food may have been what drew them north from Mexico in the eighties. “The population stayed strong in Mexico” even after people decimated the bears on the Texas side of the border, says Skiles. “In the forties, the habitat of the area in Texas began to recover from grazing, logging and people living there. It’s hard to say whether the protection of the bears was important or the habitat needed to recover, but after 50 years of seeing mostly migratory males, we started to have more bear sightings.” The population in Mexico may have grown too large for the local food supply, he adds, and large fires in the Sierra del Carmen could have joined the forces that sent the bears northward.

 

Skiles says that by 1988, the park had 25 sightings in a year, a number that climbed to 572 sightings in 1996. The evening before my hike to the bear trap, a small male appeared just outside the lodge dining hall, pulling visitors away from their dinners as they excitedly watched him through the window.

 

The small male was breaking the rules, and his appearance so close to civilization in the park was unusual. But, as the park service likes to say, there are no problem bears, just problem people. “We’re extremely pleased with the result of our proactive approach to bear management,” Skiles says. “We’ve had only a few cases where bears have entered a campsite and attempted to get food.” Leaving food around for bears is a people problem that becomes an animal-management issue.

 

But the park had the advantage of being able to manage an animal population before it was even established. “When the bear population started to grow, we decided we wanted to be the first national park in the country to implement cutting-edge technology before we had a problem,” Skiles says. The park service has a history of doing things wrong when it came to bears -- pictures of grizzlies dining at the garbage dumps in Yellowstone presaged the park’s bear-management difficulties. “The visitors who watched the bears at the garbage dumps didn’t see the aftermath of the ones who got so aggressive that the rangers had to kill them,” Skiles says. “These parks had to go through a painful process to separate people and bears, and they could tell us what we needed to do so we didn’t reinvent the wheel. But no one had ever done this before the problem started.”

 

Skiles describes a multi-pronged approach to bear management. Education is key. “We want to teach people how to visit the park without having conflict with the bears,” he says. And visitors get an eyeful in every visitor center and in every brochure they see. The park newspaper features a two-page spread on bears, giving advice on how to live safely with wild animals (see sidebar) and providing visitors with updates on bear research. The park even offers a special brochure on the return of the black bear.

 

In addition to education, Skiles lists staff training, research, and facilities that discourage bear-people contact as paramount in keeping the bears wild. “We train staff to capture and move bears humanely and safely, we’ve changed our waste management from open-top trashcans to bear-proof dumpsters, and we’re using research to develop a scientific basis for our management actions. Our goal is to have a bear population that is wild and is not influenced by human activity.”

 

But bears can occasionally send even the best-laid management plans awry. “We have had one occasion to relocate a bear,” Skiles relates. “It was an orphan bear that found a great food source -- acorns in a tree near cabins in the park. It was up a tree, drawing a heck of a crowd. People started showing up with picnic baskets, and the fear was that people might feed the bear. So we relocated it to another drainage nearby, hoping it would find another tree. It wasn’t really a problem bear, and the solution seems to have worked.”

 

Even though the park service’s efforts have been a success, the success of the bear population is not assured. Because Candy/Bear #7 may be the Mother of All Big Bend Bears, the park population could be closely related. Problems with inbreeding and a lack of variation may arise. “Even under the best conditions, this will be a small population,” Skiles says, “although the genetic quality may be OK if migrants from other mountain regions come in.” Skiles also mentions the possibility of bringing in other bears to help improve diversity. “We’ll do whatever is needed in the best interest of the bears here.”

 

But success is not guaranteed even with all of the careful efforts of the park service. This year alone has seen the loss of one of the park’s most famous bears -- Little Mama -- and her cubs. Newspaper stories about bears in the park had featured Little Mama’s picture, and she was something of a celebrity. “They died in September,” Onorato says, shaking his head. “She died in the desert in a wash, and there were cub prints behind her. We suspect dehydration.”

 

Little Mama and her kind are members of a keystone species, a species that anchors the ecosystem of an area. If they disappear, the ecosystem gets out of whack. “Black bears eat mostly vegetation, but they are also top predators,” Skiles says, “and they have a big effect on the vegetation community and what is growing where. Their return has made a big step forward.”

 

The big step forward has not left the bears in the clear. Onorato traps the bears using a combination of irresistible bear attractants, including sardines, tuna and Alaskan Fish Fertilizer, which he sprays around the traps. When he’s trapped a bear, Onorato takes blood samples and analyzes them to establish family connections based on DNA. The results -- which indicate close relationships -- underscore the potential fragility of the Big Bend population.

 

“We want to get a handle on what the genetic integrity of this population is so we’ll know if the population is diverse enough to sustain itself,” Skiles says. “Our outlook is positive, but guarded.” Skiles estimates that the park can support a population of about 30 bears.

 

A small population of only 30 bears can make a big difference in the ecological balance of the Big Bend area. “During the period they were missing, there was a big gap,” Skiles says. “When they weren’t here, the park was not complete.”

 

The bears balance the park for visitors, too. Visits in the eighties delighted with the occasional javelina sighting or frightened with the sound of a unseen rattlesnake, but nothing compares to driving into the Chisos Basin and seeing the now-familiar sign: yellow background with a black bear silhouette. The park wouldn’t be complete without it.

 

This piece appeared in Texas Parks and Wildlife Magazine.

ejwillingham (at) gmail.com

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