Comparison of the flocking behavior of Katahdin and Rambouillet sheep breeds in an extensive range environment using GPS technology

Abstract Background There is considerable interest in the suitability of the farm-flock Katahdin hair sheep breed for large-scale extensive range sheep production systems. Flocking behavior or “flockability”, a measure of gregariousness, is critical for sheep to produce in extensive, herded management systems. An evaluation of the Katahdin breed in a Western U.S. range environment compared to the traditional range-adapted Rambouillet breed is underway. The objective was to compare the flockability of range-reared Katahdin ewes to Rambouillet ewes during the summer grazing season using GPS collars. Flockability was measured by how far a ewe was dispersed from the centroid of the study flock and the total daily distance traveled compared to the study flock. Results Complete GPS coordinates were available from 23 Rambouillet and 29 Katahdin ewes in 2023 and five Rambouillet and five Katahdin ewes in 2024. Study groups were managed in bands of 800–1,000 ewes with lambs. During the day, the Katahdin breed had a farther dispersion from the study flock centroid for one of the study groups (P < 0.05), the Rambouillet breed was more dispersed for one study group (P < 0.05), and the breeds did not differ for one study group (P > 0.05). The effect size, measured using Cohen’s d, was small for all groups. The daily distance traveled was farther for the Rambouillet breed in two study groups (P < 0.05) when compared to the Katahdin breed, but did not differ for the other study group (P > 0.05). The effect size was low regardless of significance. When individual ewes were compared, both breeds had ewes that were either closer or farther away from the flock centroid (P < 0.05) or ewes that traveled farther or shorter daily distance (P < 0.05). Conclusions The Katahdin breed was similar in flockability to the traditional, range-adapted Rambouillet breed, indicating that the Katahdin breed is well suited for grazing in an extensive range environment. This study indicates the Katahdin breed exhibits favorable behavioral characteristics to flock well in large-scale extensive range systems and provides an opportunity for Western U.S. producers interested in incorporating this breed into their flock.