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Rangeland beef cows spend approximately six months annually raising their calves. This endeavor is known to significantly alter a dam�s grazing behavior and spatial distribution. The objective of this study was to characterize cow-calf interactions in two herds of Raramuri Criollo (RC) cattle that grazed rangeland pastures in southern New Mexico, USA (NM, 4355 ha) and west-central Chihuahua, Mexico (623 ha) during March and late-April respectively. At each site, five to nine randomly selected mature nursing cows were fitted with Lotek 3300LR GPS collars and Sirtrak proximity loggers. GPS collars recorded animal position at 5-min intervals, whereas proximity loggers were programed to record mother-offspring contact events at <3m distance. All calves were <2 weeks old at the onset of the study. In 2015 and 2016, respectively, collared animals grazed with a herd of 30 and 35 cows at the NM site and with 68 and 87 cows at the Chihuahua site. We computed number of contact events and duration of each event for 24h time periods, and for daytime and nighttime hours for the first three-weeks. ANOVA was used to determine if contact events and duration of each event changed as a function of calf age or time of day (day vs. nighttime). We also determined whether daily area explored by a cow and its calf differed. Day vs. nighttime mother-offspring contact events and contact time were not different (P?0.05). Dams explored larger areas of the pasture than did their calves on any given day (40.3 vs. 29.2 ha; P=0.03). Cow-calf interactions tended to decrease and mother-offspring difference in daily area explored tended to increase as calves aged. Our results suggest that RC calves follow their dams during daily grazing bouts and are likely to constrain their dams� feeding site selection the most during the first weeks after calving.