Bringing Balance to the Jornada
Some of the world’s greatest diversity of desert plants and animals reside right here in the United States among our nation’s lush watersheds and rangelands. The nation’s deserts are home not only to an impressive variety of species, but they are also home to ranchers, livestock, and traditions extending centuries into the past. The Agricultural Research Service (ARS) is committed to advancing agricultural and ecosystem sustainability in the deserts of the Southwest.
One such place is ARS’s Jornada Experimental Range (JER) in Las Cruces, New Mexico. There, scientists observe and gather long-term information about how desert species, environment, and agriculture intertwine and affect one another.
The 192,434 acre Jornada is located within the Chihuahuan Desert, the largest desert in North America. This desert region covers nearly 140,000 square miles and is one of the most biologically diverse arid landscapes in the world. Many parts of the desert, however, are known as “desert grasslands” that support extensive livestock production and have supported generations of ranching communities.
The JER—originally the Jornada Range Reserve—was established in 1912 under President William H. Taft, within USDA’s Bureau of Plant Industry. It was transferred to ARS in 1952. Since then, research at the Jornada focused on five principal themes: ecosystem science, rangeland management, land monitoring, rangeland improvements, and rangeland livestock production and husbandry. This long-term research revealed how heavy grazing and drought caused reductions in grass and increases in shrubs—changes that continue to limit livestock production and ecosystem health.
JER is currently under the watchful eye of Brandon Bestelmeyer, an ecologist and research leader at the ARS Range Management Research Unit in Las Cruces. Bestelmeyer works with ARS colleagues Rick Estell, Sheri Spiegal, and Alfredo Gonzalez; Leticia Lister at the U.S. Department of Interior’s Bureau of Land Management; and Robert Schooley at the University of Illinois. The group is focused on two management strategies: developing new livestock types to help ranchers adapt to vegetation change and methods to actively manage vegetation through restoration.
“These two strategies work hand in hand—heritage cattle breeds like the Raramuri Criollo are well adapted to shrubby landscapes, but we can also manipulate parts of the landscape to promote grasses, livestock production, and biodiversity,” says Bestelmeyer.
Heritage Cattle make a Comeback
Raising beef cattle in the western United States can be challenging. According to USDA data, as of early 2014, the number of cattle and calves raised in New Mexico fell for the fourth year in a row, to fewer than 1.3 million head of cattle.
In the early 2000s, staff at the Jornada began building a herd from a little-known cattle type called Raramuri Criollo from the Copper Canyon area of Chihuahua, Mexico. These heritage cattle are descended from Spanish cattle brought over by the Conquistadors in the 15th century. The harsh, shrubby environment from which these animals came suggested that they might be well-matched to shrubby, desert areas across the Southwest.
The JER research team and collaborators have initiated studies to compare Criollo with other cattle types common to the Southwest. "Preliminary data suggest these small frame cattle may consume different plants and require less supplementary feed than conventional breeds," says Estell.
Initial studies indicate Criollo may travel further from water and therefore have less concentrated impact on grasses. Based on these early results, JERs Criollo herd has caught the attention of several cattle companies across the Southwest. A few producers have incorporated Criollo cattle in their herds and have been pleased with the results.
Bestelmeyer, in collaboration with Schooley, is studying the impact of restoration practices on vegetation and animal biodiversity in the Chihuahuan Desert. LTAR allows widespread assessment of the relationship between agriculture and native species and the sharing of that information across the 18 LTAR sites.
In desert grasslands, aircraft are used to apply shrub-specific herbicides to promote grass recovery. Little is known, however, about the effects of these treatments on plants and animals across the landscape. Bestelmeyer and colleagues are studying the responses of several animal species at a number of treated and untreated sites, including breeding birds.
The team learned that bird responses to herbicide treatments depend on their varying preferences for grassland, mixed, or shrub dominated habitats. Treated areas had greater grass cover and less shrub cover than untreated areas. As predicted, more native birds that favor grassy environments were found in treated areas. Shrubland bird species were found in untreated areas where shrubs grew; these birds could be negatively affected by shrub removal.
“Our results indicate that shrub removal created novel savanna-like habitats that can have positive effects on grassland specialist species, but that a mosaic of treated and untreated areas might be the most beneficial for regional biodiversity,” says Schooley.
These early results suggest that selective management of shrubs and new cattle varieties adapted to shrublands can produce a win-win situation for production and biodiversity. Future plans will focus on promoting grass recovery using new seeding strategies and using sensor-based technologies to reduce the cost of managing extensive ranches.”—By Sharon Durham, ARS Office of Communications.
Editor’s note: This article is an update to the version originally posted on October 1, 2017. This version provides a broader overview of 1) Raramuri Criollo cattle and how Southwest cattle companies are introducing Criollo cattle into their herds; and 2) restoration practices across desert grassland ecosystems as a whole.