Stories abound concerning cow behavior on Western rangelands in both historical and newer accounts by men and women who spend their days with livestock. Consider this excerpt by the late and great cowboy poet, Baxter Black, from his dissertation on cow stupidity:
“On the open range, once a cow finds a waterhole, they can find it again – even if there is no trail.
It’s almost like they have their own GPS, like the geese do – to guide them.
Witness their ability to hide their calf, walk a mile and a half to water and then return to the calf’s hiding place.
Is it instinct or intelligence?”
Nature versus nurture
Our recent research suggests that “efficient” 2-year-old lactating cows use rugged rangelands more sustainably than “inefficient” 2-year-old lactating cows. Cows that were previously ranked as more efficient (using data from GrowSafe feeding units) climbed higher at Rinker Rock Creek Ranch (RRCR) during the hot days of August.
Are the differences in grazing behavior observed in efficient versus inefficient cattle grazing rugged rangelands due to nature or nurture? How important is the role of social learning? In their research, Karen L. Launchbaugh and Larry D. Howery reiterate the premise that the “most important models for social learning for a young animal were its mother and young companions.” Furthermore, they state, “Mother markedly influences the establishment and persistence of her offspring’s diet and habitat-selection patterns.”
If the differences in grazing rugged rangelands can be attributed mainly to genetic influences, then the selection of replacement heifers could be aided by using genetic markers as those become available. The research studies mentioned above from New Mexico State University and the University of Idaho (U of I) suggest that the use of these terrain genetic markers may become possible in the decades ahead.
Numerous studies suggest that the influence of “mother” declines as offspring mature. Anecdotal and scientific studies also affirm that younger animals grazing rangelands spend less time following the mother, as she is engaged in morning and evening grazing bouts, and more time in the presence of “guard” or “babysitter” cows. As a calf starts eating more forage and relying less on its mother’s milk, the opportunity for social learning may increase. Calves aged 2 to 3 months can be expected to consume approximately 20% to 40% of the dietary calories from forage and up to 40% to 70% at 3 to 5 months (depending upon year and cow milk production).
Not only is it important to have resilient rangelands, but it is also important to have cows that fit those rangelands, especially as the climate transitions to hotter, longer summers. As we search for the optimal cows, it is important to determine how cattle distribute over rugged rangelands and how that is influenced by both nature and nurture.
U of I research project
We hypothesized that calves from efficiently ranked cows would follow the mother as the calf aged and temperatures increased; and we predicted that grazing behavior would differ, with calves from efficient cows accessing more difficult slopes and spending less time resting during the heat of the day than calves from inefficient cows. Additionally, we hypothesized that cows differing in feed efficiency would exhibit differences in grazing behavior and grazing distribution, with efficient cows traveling further and grazing more of the available pasture. We also hypothesized that efficient and inefficient cattle would differ in the amount of time spent grazing, resting and walking.
Experimental pastures and animals
This two-year research project occurred at RRCR, 11 miles southwest of Hailey, Idaho. There were 35 3- to 8-year-old cows and their calves (17 efficient, 18 inefficient), which carried grazing collars containing both accelerometers and GPS loggers. Accelerometers are used on rockets to measure velocity in three directions and can be paired with cattle head movements to determine foraging behavior. Cattle grazed upland range pastures with the rest of the 165-cow herd from approximately mid-May until mid-October, with calves being weaned in mid-September. Grazing locations and other GPS data were determined at five- to seven-minute intervals and daily accelerometer activity was evaluated at five-second intervals. Collars were installed at turnout on May 19, and then each cow and calf had their behavior (grazing, resting and walking – plus suckling for calves) observed in a smaller pasture over four days in order to obtain a “data signature” for the recorded accelerometer data. Collars were removed after 27 days and then reinstalled in July, following the same procedures.
![60867-sprinkle-behavior.jpg](https://www.agproud.com/ext/resources/2025/01/03/60867-sprinkle-behavior.jpg?1736185219)
This map shows a cow (green dots) and her calf (purple dots) on July 16, 2021. The cow grazed for 10.6 hours, rested for 11.9 hours and walked for 1.5 hours. The calf grazed for 6.9 hours, rested for 16 hours, walked for 0.7 hours and nursed for 0.5 hours. Nursing was about 50% of the average on this day. On this day, the cow spent 8.2% of her time on slopes greater than 15%, while the calf only spent 0.7% of its time on steeper slopes. Image provided by Jim Sprinkle.
Preliminary findings
We are still analyzing data from this project, but preliminary findings suggest that both inefficient cows and their calves tend to arise earlier in the morning to start grazing flat meadows in July. This is indicative of the greater appetite associated with inefficient cows. This association did not hold true as cattle were moved to steeper pastures, but inefficient cattle tended to graze later into the morning. On days with increasing heat load, efficient cows tend to walk more than inefficient cows, but when wind and cooler temperatures prevailed, inefficient cows traveled one and a half hours longer and 2.6 miles further as they engaged in search grazing to acquire better nutrients. Inefficient calves accompanied their mothers on the long travel day, but on the day following, fatigue resulted in their being a greater distance from their mothers at lower elevations than the efficient calves (-951.4 versus +0.3 feet). As temperatures increased in July of both 2021 and 2022, calves from efficient cows tolerated and used more south-facing slopes than did calves from inefficient cows. Efficient cows and their calves appear to have greater heat tolerance than inefficient cows. Our research has shown that much of this can be attributed to a larger gastrointestinal tract size for inefficient cows. Think of this comparison; which engine would generate more heat in a car, a big-block hot rod engine or a small V6 engine?
The map image presents the grazing behavior of an inefficient cow and her calf on July 16, 2021. Both cow and calf were lying down in the same bedding ground from midnight until early morning. When the cow went to water on the southeast corner of the pasture, the calf stayed behind. At around 10:41 a.m., the cow started grazing toward water on the northeast corner of the pasture, and the calf was following by 11:20 a.m. Both cow and calf were resting at the northeast part of the pasture by 13:06. The cow got up to graze in the lower part of the pasture at 16:23. At 18:13, the cow commenced grazing towards the uplands, and the calf did not follow, preferring to graze at lower elevations.
The data presented in the map image lends support to the “babysitter” cow concept. A study in New Mexico showed that younger Angus-Hereford calves spent most of the day close to a guard cow and did not travel with their dam during morning and afternoon grazing bouts. In this respect, these calves are considered to be “intermediate or weak followers.” Conversely, some heritage breeds, such as Criollo, exhibit “strong follower” behaviors, which may alter the use of rangeland pastures.
We will continue to analyze these data over the next several months, and we plan to pair our results with the DNA markers we hope to examine. By doing so, we hope to unlock the genetic (nature) versus social learning (nurture) aspects of cow and calf grazing behavior.
References available upon request by sending an email to an editor.
The Nancy M. Cummings Research, Extension and Education Center (NMCREEC); Landon Sullivan, Ph.D. graduate student, NMCREEC; John Hall, U of I Extension beef specialist, NMCREEC; Scott Jensen, U of I area extension rangeland educator; Benton Glaze, U of I Extension beef specialist, Twin Falls, NMCREEC; Morgan Stegemiller, Ph.D. graduate student, U of I Animal Veterinary and Food Sciences (U of I AVFS); and Brenda Murdoch, associate professor, U of I AVFS also contributed to this article.