Texas Parks & Wildlife Magazine   

Archives

Playas in Peril

Shallow Panhandle lakes serve multiple functions, from acting as a rest stop for ducks to recharging the Ogallala Aquifer.

By Russell A. Graves

It’s late January in the far north Texas Panhandle, and like the rest of Texas this year, it’s dry. Here, it’s been nearly 120 days since the last measurable rainfall, and dust wafts from the land with even the slightest puff of wind. The ground is parched, yet Spearman rancher Bob Pearson and I are in search of Panhandle wetlands.

Creeping along in Pearson’s truck, we ease past a wagon trail whose deep, grass-covered ruts cut an old road that leads from the Canadian River bottom north across the shortgrass plain. Soon we are at the edge of a 60-acre sunken depression. The broad, round spot is a playa (pronounced PLY-yuh) lake, and it is one of an estimated 19,000 shallow water basins that make up a huge complex of wetlands that cover the northern Panhandle down through the Southern Plains to around Lubbock. Although the lake is dry now, the thick and dormant vegetation hints of a wetter time in the recent past.

Around the ancient lake, I don’t see much in the way of traditional agricultural manipulations, like row-cropping or terracing. Pearson, along with his brother and ranching partner, Doc, are past winners of the Texas Parks and Wildlife Department’s Lone Star Land Steward award. They both enjoy the fact that their family ranch is largely unchanged by man’s influence.

“This land has been in my family since the 1940s,” explains Pearson. “My dad got this ranch from the family who originally homesteaded the place back in the 1880s. Since I can remember, my dad loved the playa lakes on this ranch, and he was careful to never plow around the lakes for fear they would silt.” Pearson, now in his late 50s, plans to continue managing the ranch in the same way his dad did. “My dad was a conservationist before anyone knew what the word meant. He instilled an ethic in me to take care of this ranch and take care of the lakes.”

Even now, when the lake is bone dry, Pearson still finds beauty in the wetland. “When the playa is wet, all kinds of waterfowl and birds flock in here,” he says. “When it’s dry, wildlife still uses the lake. I won’t be surprised if we see … ” He pauses and points to the east. In the grass, 50 yards away, I see the unmistakable form of deer antlers sticking up through the dried smartweed. In the taller weeds around the lake’s margin, I see a couple of gray bodies slipping through the weeds. “There are always mule deer hanging out in these lake bottoms. They’ll bed in the high weeds and feed on some of the plants that grow in the wet soil.” In the course of an hour, I see jackrabbits, mule deer, a few whitetails, quail and numerous songbirds around the 60-acre playa. All are animals not typically associated with wetlands, but ones that benefit from the shallow basins nonetheless.

For centuries, the wet-dry cycles of the high plains wetlands benefited wildlife and plant life alike. Since the Clovis period of 11,500 years ago, ancient people benefited from the lakes as well. Artifacts discovered in an ancient Roberts County playa (just a few miles southeast of here, near Miami) include spears and scrapers found in proximity to elephant bones. People of the Folsom period (10,900 – 10,000 years ago) supplemented their bison diet with various aquatic animals and ducks they captured from playas.

The term playa is Spanish in origin and literally means beach. Perhaps Francisco Coronado coined the term when he crossed the plains in search of the fabled Quivira — the lost city of gold. Pedro de Castañeda traveled with Coronado on the expedition and made note of the playas in the mid-1500s. “Occasionally there were found some ponds, round like plates, a stone’s throw wider or larger,” he wrote. “Some contained fresh water, others salt.”

Throughout recorded history, the playas, which are the main water source on the plains, drew American Indians and 19th-century settlers. Comanche, and later hide hunters, knew that bison drank from the playas and often hunted them at the water holes. In fact, one of the theories that attempt to explain the origins of the playas suggests that bison wallowing in the mud over time caused the depressions. Still known as “buffalo wallows” by many contemporary plains residents, playas were actually formed by decaying organic matter that formed carbonic acid and dissolved the caliche soil layer. Once the caliche layer dissolved, various materials such as rock and organic matter permeated the soil and eventually formed a layer of clay in the bottom of the lakes that, when wet, is impermeable.

As more settlers moved into the Panhandle, farms and ranches sprang up around the playas. Over time, however, many playas were partially filled in or entirely eliminated as the area evolved into the agricultural breadbasket of Texas. Bill Johnson, a TPWD wetlands biologist based in Canyon, says that most playa degradation came from agricultural practices such as irrigation ditching and close-proximity plowing. Although the rate of destructive practices has slowed considerably, Johnson estimates that at least half of the playas that originally existed in Texas have been severely damaged or destroyed.

“Although they represent only two percent of the landscape in the Southern High Plains, playas are key to both floral and faunal diversity,” explains Johnson. “They are the primary wetland feature in a very arid landscape — without functioning playas, both plant and animal diversity in the Texas High Plains would be very low.” Johnson says that, during the peak of the winter, as many as half a million ducks are on the lakes in wet years. During the fall and spring migrations, that number increases substantially. “The numbers of ducks, geese, cranes and shorebirds that use playas during migration periods and winter can be quite impressive. Without functioning playas, it’s not a stretch to say that waterfowl numbers would be affected on a continental level.”

However, waterfowl and shorebirds aren’t the only avian species that utilize playas. The Panhandle’s premier game bird, the ring-necked pheasant, is inexorably tied to the shallow water lakes. According to Texas Tech University researchers, pheasants spend as much as 90 percent of their time around playa lakes during the nonbreeding season. Without playas, pheasant numbers and, ultimately, the local hunting economies would suffer. Towns like Hart and Nazareth host huge groups of pheasant hunters annually, and their presence is essential to maintaining a vigorous local hunting economy even when the broader agricultural economy is marginal.

As important as playas are to the plants and animals above ground, they are absolutely essential as sources of recharge for the vast underground Ogallala Aquifer. For every gallon of water the lakes hold on top of the plains, countless millions of gallons of precious water lie just beneath the surface in the aquifer. Johnson explains that one of the big dangers that threaten to degrade the wetlands is sedimentation. Soil loosened by plowing and intense livestock traffic around a playa’s margin can wash into the lakes with rainfall. Excess sedimentation affects the playa’s ability to soak up water and reduces the amount of recharge to the aquifer that lies beneath.

“Maintaining wide, healthy grassland buffers adjacent to playa lakes is the best way to protect them from sedimentation. Many U. S. Department of Agriculture farm bill programs, such as the Conserv-ation Reserve Program, can provide cost-share to plant or restore grassland buffers around playa lakes. The Texas Parks and Wildlife Department’s role in playa restoration projects is to work closely with federal and state agencies and, most importantly, private landowners. Landowners are the key to playa lake functionality because 99 percent of playas lie on private land,” explains Johnson.

Daryl Birkenfeld, director of the Naz-areth, Texas-based Ogallala Commons — a group dedicated to protecting the region’s land and water resources — underscores playa lakes’ role as the lifeline for the aquifer. “The largest concentration of playa lakes in the entire world happens to occur across the top of the Ogallala Aquifer. Playas are naturally tethered to the Ogallala; when playas are in a dry cycle, their clay-covered basins form large cracks. When a significant amount of rain falls in a short period of time, the cracks in the soil allow recharge of the aquifer during the first 24-48 hours of the rainfall event.” After the initial deluge, the cracks close and seal the bottom from further percolation. Even though the recharge period is brief, the lakes’ contribution to the aquifer is significant. In fact, a significant rainfall on the plains proper may only contribute a tenth of an inch of water to the aquifer level while a single playa lake can contribute three to six inches of water from the same downpour. Ultimately, playa lakes are the only significant source of recharge for the Ogallala Aquifer.

That’s why sedimentation is such a danger to the wetlands. When sedimentation fills a lake, the depth is reduced and the water spreads over a broader area and evaporation accelerates. More detrimental, however, is when the sedimentation fills the cracks in the playa’s clay bottom, thus shutting off recharge. Since no state or federal legislation protects playa lakes, Birkenfeld is afraid that the intense drawdown of the Ogallala Aquifer and indifference to playa lakes by landowners, could lead to the loss of the wetland complex and irreparable damage to the lakes and the aquifer over the next 20 years.

“Clearly, without functioning playas, it will be impossible for us to preserve the Ogallala Aquifer over the long term when we are withdrawing a foot or more from the water table every year,” warns Birkenfeld. “In much of the central Southern Plains, where the concentration of playas is as high as one per square mile, if these playas are conserved and remain functioning, then recharge from healthy playas could play a major role in stabilizing the Ogallala Aquifer and help to preserve it for generations.”

back to top ^