Social interactions and movement patterns of rangeland-raised beef cows and their calves

Abstract

Understanding the spatial and temporal relationships between beef calves and their dams is crucial for effective rangeland management. This study investigated these dynamics on semiarid rangeland using GPS collars fitted on cow-calf pairs. Data were collected on 46 crossbred cows and 34 calves grazing two adjacent 219 and 146 ha pastures. The primary objective was to determine the proximity of calves to their dams and other adult cows at different calf ages (1, 2 and 4 mos.). Over a 24 h period, calves spent on average 10.5 and 17.5 h within 5 or 10 m of an adult cow, respectively, and spent 2.6, 5.6 and 2.3 h within 5 m of their dams, other adult cows and a guard cow (cow other than the dam that spent the most time in the proximity of a calf), respectively. Calves spent more time within 5 or 10 m of an adult cow during night vs. daytime hours and spent detectably (P < 0.05) more time within 5 or 10 m of other adult cows vs. their dam (5.6 vs. 2.6 or 10.3 vs. 3.5 h). Calves spent a similar (P > 0.05) amount of time within 5 or 10 m of their dam vs. the guard cow (2.6 vs. 2.3 or 3.5 vs. 3.7 h) regardless of age during both day and nighttime hours. In general, calves spent more time within 5 and 10 m of an adult cow at 2 vs. 1 or 4 mos. of age. Greater mother-offspring clustering occurred at 2 vs. 1 or 4 mos. of age regardless of the spatial threshold considered. Regardless of calf age, calves and nursing cows traveled on average 4.5 and 6.7 km/day, respectively. Calves at 4 mo of age traveled farther than younger calves. Nursing cows traveled farther when calves were 4 mo. vs. 1 or 2 mos. of age and tended to travel farther when calves were 1 vs. 2 mos. old. Calves spent more time close to other nursing cows vs. their dam. These findings suggest that while dams play a crucial role in calf development, other nursing cows may also influence their foraging behaviors. Further research is needed to fully understand the dynamics of these relationships and their implications for rangeland management, such as optimizing grazing strategies and improving calf health and productivity.