Meet the bighorn sheep of the Río Grande Gorge

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The sun was still a ways below the eastern horizon when a small gathering of people — mostly scientists and game warden types — gathered at the snowy, silent edge of the Río Grande Gorge. Day began to break. Definition returned to the landscape from the darkness; the ups and downs of the sage-covered mesa on the west side of the river not yet stolen away by the sun. Long-range spotting scopes and binoculars, not guns, were the tools of choice. Braced and buckled for the cold, they were ready for a hunt of sorts.

The crew has to walk carefully across the land — maybe not as quietly as if they were actually hunting, but just as attentive.

Just days before Thanksgiving, they were walking the gorge for an annual census of the bighorns, an animal that, across the West, is slowly making its way back from the brink of total eradication.

Ten years after bighorns were brought to the gorge, the herd is not a floundering experiment, but a fully established, independent herd of more than 300 animals.

Near extinction, reintroduction

Much like the river otters that now swim in the river at the bottom of the gorge, bighorn sheep were — up until not that long ago — a big part of the order of things in the southern stretch of the Rocky Mountains we call home.

The Rocky Mountain bighorns and the desert bighorns are the only two subspecies of bighorn sheep in New Mexico. It’s a meeting in the middle. The Rocky Mountain type, as their name suggests, historically roamed the mountains from Alberta, Canada, all the way south to New Mexico. The desert bighorns, on the other hand, show up just south of I-25 and can be found well into Mexico.

And like their otter neighbors, the bighorn sheep were whipped from the landscape.

According to Eric Rominger, bighorn sheep biologist for the New Mexico Department of Game and Fish, bighorns were extirpated in New Mexico around the turn of the 20th century. The last known evidence of a bighorn in New Mexico was a track found in the Truchas Peaks south of Taos.

The reintroduction of the bighorn sheep started in the 1940s when a group of sheep were gathered from Alberta and brought to the Sandias. A herd was started in the Pecos Mountains with a mix of fresh blood from Alberta along with a few Sandia sheep — the founding stock for many of the rest of New Mexico’s herds.

When Rominger came to the department in 1996, bighorns were officially endangered. Only 166 desert bighorns and fewer than 600 Rocky Mountain sheep were present in New Mexico. Now, he said, there are 15 herds spread across the Land of Enchantment.

Sheep from the Pecos were brought to the Wheeler Peak Wilderness in 1993. As Michael A. Martinez, hunt coordinator for Taos Pueblo’s wildlife office, said, “Of course, they eventually made their way on the pueblo side. The majority of those bighorns winter on the pueblo side’s abundance of south-facing slopes, moving back to the public side during the summer.”

Then, in 2005, the Taos Pueblo war chief, lead biologist and director of wildlife decided to try to bring the bighorns back to the inverted mountain landscape of the gorge. Taos Pueblo took an initial group of sheep from its side of the Wheeler Peak chain, and the state department supplemented the herd in 2007 with more sheep from the Pecos.

“So much has been done to wildlife and the environment in general,” Martinez said.

“The pueblo tries to maintain the lands as naturally as possible,” he said. Bighorns were known to span the Upper Río Grande area; a petroglyph of a ram was once carved into the rock of the gorge. Aside from habitat management, bringing the environment back to what it once was has meant massive projects, such as the reintroduction of the bighorns.

Handy in the gorge, but hard to see

Bighorns are “pretty handy” in the cliffs of the gorge, over steep and open terrain, Rominger said. They make their way up and down the gorge. During low water, they wade across the river or even jump from rock to rock in order to make it back and forth. And during the rut, rams — whose spiraling horns can weigh up to 30 pounds — have far larger home ranges up and down the river than during the rest of the year.

When it comes to finding food, bighorns are adept at using what’s at hand in the gorge. “Really, they like whatever is greenest on the table,” Rominger said. Whereas deer are pretty strict browsers and elk pretty strict grazers, sheep “bridge the dietary gap,” Rominger said.

But sometimes, bighorns are the dinner. Rominger said that while the sheep can outmaneuver smaller predators, there’s evidence — bodies, tracks and sightings — of mountain lion kills.

Scientists know the broad strokes of what the Río Grande bighorns are up to, but there’s always need for better data to drive more habitat improvement in the area.

No sheep in the gorge were ever tagged with GPS collars, which can pinpoint their location within 3 feet. When the first sheep were introduced, some had radio collars (meaning field biologists could track them down). Only three collared sheep were found in the November census. But the youngest collared sheep is at least 11 years old; most sheep don’t live beyond 15 years.

On the day of the annual census, the biologists and field crew spread out on the west side of the gorge from the high bridge on U.S. 64 to the low bridge in Pilar. (The east belongs to Taos Pueblo, which usually conducts a census of the bighorn sheep at the same time). Each person took a mile or so, walking slowly enough to spot the sheep camouflaged by crags and snow.

Only 223 sheep were spotted during the census, down from 245 observed last year.

But Rominger said the drop doesn’t likely reflect an actual drop in population. “We know we don’t see them all. We didn’t really see up the Río Pueblo de Taos and survival tends to be high in the herd. We don’t really have any reason to think they’ve declined,” he said.

Rominger estimates the actual population of the Río Grande herd is closer to 330 to 350.

Hunting for conservation

Unlike some fields of scientific inquiry (the study of spiders, for example), there’s lot of money in bighorn sheep. That’s why Rominger turned down a professorship to take the job as bighorn sheep biologist for the state.

“We don’t hunt an animal until it’s well established,” he said.

Bighorns are some of the most expensive animals in the world to hunt. The record-high price of a tag in New Mexico stands at about $270,000. In other parts of the West, tags have sold for half a million. That money, he said, fuels the science and fieldwork behind recovery efforts.

“We have to recognize the importance of hunter-conservationists,” he said.

On the part of Taos Pueblo, hunting is a tool used to help manage the population. Once the sheep were reintroduced a decade ago, Martinez said, that prodded Taos Pueblo to do even more habitat improvement for the land and environment in the gorge. Those efforts benefit the whole ecosystem, not just the sheep, he said.

According to Rominger, only seven rams have been harvested from the gorge since the herd was established. No tags were sold from 2006 to 2014, two licenses were sold in 2015 and five in 2016. All of those have scored in the heist echelon of world records.

Bighorns in human landscape

But the great gift of the bighorns’ close proximity comes at a cost.

Sheep tend to die closer to urbanity, and a tourist attraction of a bridge with vendors, visitors and more or less constant vortexes of traffic certainly count.

Road strikes aren’t unheard of, said Rominger. Last year alone, three rams were killed in traffic collisions on the eastern side of the gorge.

The second, though far more deadly, risk the human landscape imposes is that of disease – particularly “old-world” diseases transmitted from domestic sheep to the native, wild herds. Domestic sheep don’t get sick with these diseases, but if they even go nose to nose with a wild bighorn, the mortality rate is sure to be between 50 and 100 percent. As Rominger said, disease from domestics is the bane of sheep biology across the West. “Some states, like Idaho, have fewer sheep today than they did 20 years ago,” he said. New Mexico, thus far, hasn’t seen a major die-off.

But there’s no silver bullet — no vaccine to introduce. “All we can do is just keep them from commingling with the domestics,” Rominger said.

The best Taos Pueblo, state agencies, scientists and conservation groups can do, he said, is try to keep domestics and wild sheep apart through fencing, double fencing and negotiations to keep land free of domestic herds.

Interestingly, for such a hardy herd, the Taos area has more domestic sheep in close proximity to the wild herd than just about anywhere else in New Mexico — a few pockets of private sheep operations in the valley and a grazing allotment near San Antonio Mountain (within the range biologists know they walk) exist.

If a wild bighorn does get together with a herd of domestic sheep, he said they try to cull it before it gets back to the rest of the herd — a game of chance dependent on people being observant and diligent in reporting what they see.

“So far, we’ve dodged the bullet,” Rominger said.

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