Tucson CitizenTucson Citizen

Damaged San Pedro River healing again


U.S. environmental regulations and cooperation from the Mexican government help make the water fit for life once more.

Down on the San Pedro River, a wandering green and blue stripe between north-south mountain ranges in Cochise County, things are looking up after a hundred years of decline.

First, in the 1980s, the water started to run more regularly and clear. Upstream in southernmost Cochise County and across the border near Cananea, Sonora, Mexico, where the San Pedro begins, U.S. environmental regulations and cooperation from the Mexican government helped make the water fit for life.

For decades, mining and agriculture had poisoned all but the river’s hardiest species. But once cleaned up, the water brought life back quickly.

Soon, the old cottonwood trees along the river were perking up, sheltering new trees and undergrowth. Volunteer groups, including inmates from the state’s DUI prison near Douglas, planted saplings. The new trees shot up quickly; some are now 30 feet tall or more, sheltering smaller plant growth.

Sacaton and other native grasses have begun to reclaim the old flood plain on both sides of the San Pedro.

The clear water, thriving vegetation and insect feast, all in the middle of a major flyway for millions of North American migratory birds, have begun attracting species not here for decades. Even wild turkeys are making a comeback.

There has been a surge in the small-mammal populations, too. Now, harrier hawks hunt just above grasstop level, looking for fast food. Larger redtail hawks scan the buffet from higher altitudes. Roadrunners work the deck.

“It is probably the largest intact riparian corridor in the West,’ Rick Gerhart, an Arizona Game and Fish Department biologist, said recently.

“Probably two-thirds of the (river-area) species that have been identified in the West have been identified in San Pedro,’ he said.

But the area hasn’t yet regained all its natural biologic momentum. At one time, said Jesse Juen, a resource area manager from the Bureau of Land Management’s Tucson office, locals pulled 3-foot Colorado River squawfish from the San Pedro. He’s seen the pictures showing old-timers holding the so-called Colorado River salmon, heads waist-high, tails brushing the ground.

W.L. Minkley, in “Fishes of Arizona,’ wrote that the Colorado squawfish was seen in the San Pedro as far south as Fairbank, near Sierra Vista, as recently as 1955.

Juen said 13 native fish species once lived in the San Pedro. Some are now extinct everywhere. But some exist elsewhere in the state or can be restocked from hatcheries in Arizona and New Mexico.

Some of the larger species, especially mammals, won’t return without a push start from man – the same species that sent them packing. Wildlife biologists refer to the beaver as a keystone species, one that will alter the San Pedro habitat to the benefit of other species.

The plan is to introduce a few beavers in the next two years.

After the beavers are established, state and federal wildlife experts and public fans of this area hope larger birds of prey, native fish and maybe someday, just maybe, wolves will live here again.

It all started in 1988 with federal legislation designating the San Pedro Riparian National Conservation Area, along the river that flows from Mexico through the broad valley between the Huachuca and Whetstone mountains on the west and the Mule and Dragoon mountains on the east.

On the flat flood plain immediately beside the river, cattle munched the grassland to the nub. Irrigation rigs, fed by rumbling diesel pumps that sucked water from under the river, sprayed the thirsty crops that lived on the soil next to the river – the same soil that was once rich and moist, thanks to the beavers’ stream-widening projects.

Most of the trees were cut for firewood to power mining pumps in the 1800s, say Gerhart and others who have researched the San Pedro’s history.

The turnaround has been remarkable. Gerhart said 365 bird species have been spotted in the conservation area, a project of the U.S. Department of the Interior’s Bureau of Land Management.

The big cottonwoods and mesquites had been cut in the mid- to late 1800s to support mining operations in Tombstone and to make room for grazing and fields.

The Bureau of Reclamation put a halt to grazing along the banks in recent years. Native grasses, such as Sacaton, struggled against Russian thistle (tumbleweed) and the grasses cattlemen preferred. But without the cattle to inadvertently till the soil, the tumbleweed died back and the native grasses flourished.

Volunteers planted trees, removed old fences, picked up litter and counted birds.

Public sentiment hasn’t all been in favor of restoring the San Pedro, said William Civish of the BLM’s Safford office. Landowners, mainly in the Benson and St. David areas to the north, feared planned land acquisition to expand the protected river area would push them out and restrict their use of adjoining private property.

BLM scaled back its purchase plans and has had many public meetings to work things out with opponents of the plan, said Civish.

Now, the major concern is over falling water tables due to ground water pumping to support nearby Sierra Vista’s rapid growth.

But Civish said progress is being made. Besides removing cattle and retiring cropland on the flanks of the San Pedro to reduce water consumption, Civish said, the Cochise County Planning and Zoning Commission has considered special low water-use regulations for new Sierra Vista housing on the west side of the San Pedro.

Still, Gerhart and other wildlife and habitat experts said, there never will be enough water in or under the San Pedro to bring back all the species that once thrived there.

There are other interests in the area besides wildlife, too. There is a Clovis archaeological site, where mammoth bones were uncovered in the 1950s. And north of Highway 92, near Fairbank, are the walls of a Spanish-era presidio.

Juen said a visitor center is planned for 1995.

Man and the San Pedro can co-exist, it would seem. Juen, standing next to an old gravel pit on a wash leading up to the San Pedro, said the BLM has decided to leave the pit. Locals stocked it with fish, mostly non-indigenous. It may be of use as a breeding pond if the time comes to reintroduce indigenous species.

“We could put a few in the river,’ said Mark Fredlake, a BLM wildlife biologist, “but it’s probably premature’ to talk about re-establishing Colorado River squawfish.

The Endangered Species Act probably would preclude any fishing for squawfish in the area anyway, said Juen.

But there is hunting. While the government guys talk about the project in a four-wheel-drive vehicle bouncing along a path parallel to the river, they pass a winter season bowhunter carrying the head of a big buck. The badge-wearers wave and nod, the hunter smiles and keeps moving. He’ll have to hurry to find some good friends to walk back in and help carry out the rest of the carcass. Otherwise it becomes dinner for the coyotes. The public is not allowed to drive vehicles in the area.

A bit farther down the path, in Carr Canyon Wash, there’s a hint of the way things were and could be. It’s probably a survivor from the old days, an 80-foot Fremont cottonwood with a 33-foot diameter.

SIDEBAR: Beaver return called benefit to river system

The “keystone’ species to the San Pedro River’s future is the beaver, says Arizona Game and Fish wildlife biologist Rick Gerhart.

Beavers once thrived along the river, but were trapped out in the mid- and late 1800s during the country’s obsession with making hats and coats out of the giant rodent’s pelt.

By building dams, beaver slow the flow of the river, allowing what water there is in the desert to spread out, sink in and form habitat for other animals and plants.

“It modifies the habitat to benefit other species,’ says Gerhart. “(Beaver) dams allow much wider perimeter of the stream. It spreads the wetted area, three to five times wider and wetter. Water seeps out gradually during dry periods. Perennial stream flow had been found to return when there are beaver.’

So wildlife experts are preparing to give Mother Nature another nudge.

Gerhart said beavers also create pools behind their dams that are perfect for some of Arizona’s threatened and endangered fish.

If all goes as planned, maybe as soon as next year, a few beaver – North America’s largest rodent (up to 4 feet long and 60 pounds) – will be reintroduced into the San Pedro.

Our Digital Archive

This blog page archives the entire digital archive of the Tucson Citizen from 1993 to 2009. It was gleaned from a database that was not intended to be displayed as a public web archive. Therefore, some of the text in some stories displays a little oddly. Also, this database did not contain any links to photos, so though the archive contains numerous captions for photos, there are no links to any of those photos.

There are more than 230,000 articles in this archive.

In TucsonCitizen.com Morgue, Part 1, we have preserved the Tucson Citizen newspaper's web archive from 2006 to 2009. To view those stories (all of which are duplicated here) go to Morgue Part 1

Search site | Terms of service