Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New bulls may revive the Texas state Bison Herd

22.11.2004


The three young bulls donated by Ted Turner to be introduced into the Texas Bison Herd at the Caprock Canyon State Park. (Photo courtesy of Chester Hawkins, Texas Parks and Wildlife Department.)


It’s a match made in heaven. Or at least in the Texas Panhandle.

Three young bison bulls were donated by media tycoon Ted Turner from his New Mexico herd. They will be introduced into the Texas Bison Herd at the Caprock Canyon State Park next summer, in hopes they will provide much needed genetic diversity.

The Texas Bison Herd originated in the late 1800s with five bison calves captured by famed cattleman Charles Goodnight. The herd was donated to the state in 1997 and moved to the park. More information about the herd is available from http://www.tpwd.state.tx.us/expltx/eft/bison/ .



But even with intensive management by the Texas Parks and Wildlife Department that includes annual vaccinations, supplemental feeding and veterinary care, the herd has produced a small number of calves over the last six years. Possibly more troubling, the average age of approximately 40-animal herd has increased by three years, said Dr. James Derr, associate professor of veterinary pathobiology with the Texas A&M University College of Veterinary Medicine and the Texas Agricultural Experiment Station.

Derr and Dr. Natalie Halbert, a post doctoral research associate in the College of Veterinary Medicine, were asked to help. "If you have a healthy, stable population that’s having a reasonable number of offspring and the old ones are dying … the average age should not significantly increase over time," Derr said. "If the population is expanding and more babies are being born than old ones are dying, the average would actually decrease. "We, as geneticists, and the Texas Parks and Wildlife Department as wildlife managers, had a concern that something wasn’t going right. The managers were doing everything they could, and the herd was not increasing in size."

While sampling the DNA and doing pregnancy tests in the fall of 2001, Derr and Halbert found that 15 of the 18 adult females were pregnant. However, by spring, when the females were due to calve, only one calf survived. The rest were either not born or did not survive long after birth. Disease and genetic problems such as chromosomal defects were ruled out. But since Derr and Halbert already were sampling the DNA from the federal bison herds throughout the United States for another project, they knew how much genetic variation there should be in an "average" bison. "When we compared genetic variation in the Caprock Canyon bison herd, we found out they had significantly less genetic variation than any of the federal herds and most any of the other state and private herds," he said.

This led them to conclude the herd was suffering from inbreeding depression. Since the herd was confined on the Goodnight Ranch and then at the state park, no new genes had been brought into the herd in 120 years. With the assistance of Dr. William Grant, a professor of wildlife and fisheries science for the Experiment Station, Halbert developed and used computer models to simulate the future for the herd under best-case and worst-case scenarios.

She used genetic and demographic information such as the natality (birth) rate and death rate based on data from the last several years in the model and examined the data year by year. "The idea is to have an estimate, not a definite, of what would happen. In the future is the population going to be driven to extinction? Or is it likely to recover? Given the current problems with natality and mortality and the lack of variation at present, it’s most likely in the next 50 years the population is probably not going to survive," she said. One solution is to bring in new genetic diversity from an outside source. "But in this herd, it’s not something you do lightly," Derr said.

First of all, this herd, since it clearly originated in the Texas Panhandle, is probably the last genetic example of what was called the Southern Plains bison, said Danny Swepston of Canyon, Texas Parks and Wildlife Department wildlife district leader for the Panhandle. When the Transcontinental Railroad was built across the United States in the 1800s, the bison were split into what was known as the Northern and the Southern herds, with the latter made up of animals from Texas, eastern New Mexico, eastern Colorado, Kansas, Oklahoma and southern Nebraska. No other animals but those from Texas have been brought in. "What we didn’t want to do is bring animals in from outside," he said.

Also, the historical link to Goodnight made researchers reluctant to tamper with the herd too much, he said. Even though Goodnight donated three bulls to Yellowstone National Park before his death, animals could not be brought back from there because that herd is infected with brucellosis, a contagious bacterial disease, he said. "Our best option was to try and find a herd that that has a historical link to Texas bison, that did not have hybrids (of cattle and bison) or diseases that could be transmitted to this herd, and had a lot of genetic variation so that the animals we bring in can immediately bring in new genetics to help overcome inbreeding depression," Derr added.

They found that with Turner’s herd. "We tested that herd a few years ago, and we didn’t find any evidence of cattle mitochondrial DNA," a sure sign of cattle genetics in the herd. So last year, Texas Parks and Wildlife representatives, along with Texas A&M researchers traveled to New Mexico and chose three 1½-year-old bison bulls. "We picked the three handsomest, orneriest, teen-aged bulls that were in there," Derr said, laughing. The bulls arrived in January 2003 and have been placed in quarantine as a precaution against disease, Swepston said.

Texas Parks and Wildlife Department staff will keep them separated from rest of the animals until the cows are bred next summer. One or two of the young bulls will be put in with three or four cows, and samples of the DNA of the offspring will be collected. Swepston said it will be a long-term project. "It will be probably be a few years before we know the results." This type of work is important, not only to bison but other wildlife as well, Derr said. "The kind of genetic technology we’re using with North American bison ...was first developed for humans, and secondly used on livestock species such as cattle," he said.

Our hope is that when these studies are completed, they will form a model of the kinds of studies using genetic technology that can be used to preserve, conserve, and reconstruct many other wildlife species populations."

Two scientific articles explaining the details of this study in the Journal of Mammalogy and in Ecological Modelling were published this month.

Edith A. Chenault | EurekAlert!
Further information:
http://www.tpwd.state.tx.us/expltx/eft/bison/
http://www.tamu.edu

More articles from Agricultural and Forestry Science:

nachricht Researchers discover natural product that could lead to new class of commercial herbicide
16.07.2018 | UCLA Samueli School of Engineering

nachricht Advance warning system via cell phone app: Avoiding extreme weather damage in agriculture
12.07.2018 | Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V.

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>