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Wildlife managers need empirical data about pronghorn (Antilocapra americana) movements in North Dakota to assess whether mid‐summer surveys represent occupancy of pronghorn in hunting units during the fall hunting season. Using data from 121 radiocollared pronghorn we evaluated patterns of pronghorn migrations in southwestern North Dakota from 2004 to 2007. Pronghorn exhibited 2 primary movement patterns between summer and winter ranges: migrations >15 km (45%) and movement <15 km (55%). Most migratory pronghorn moved northeast or east in the spring and southwest or west in the fall. Average distance moved for migratory pronghorn was 70.6 km (range = 17.4–253 km). Mean date of pronghorn migration in spring was 20 March (SD = 20 days) and in fall was 22 October (SD = 17 days). Nearly all migratory pronghorn (97%) returned to within 15 km of their previous summer range, whereas only 61% of pronghorn returned to within 15 km of their previous winter range. Most pronghorn moved across hunting and survey unit boundaries; however, only 7 fall migrations occurred between the aerial survey and the hunting season. During years of our study, the mid‐summer survey provided representative information about hunting unit occupancy of radiocollared pronghorn for the fall hunting season. © 2011 The Wildlife Society

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Wildlife managers need pronghorn (Antilocapra americana) movement information in North Dakota because harvest quotas are based on a summer population survey, which might not represent the areas used by pronghorn during the fall hunting season. We tracked 121 radio-collared pronghorn to estimate migration dates, distance and direction, as well as site fidelity for pronghorn in North Dakota, 2004Dakota, -2008 Nearly half of the pronghorn were migratory, moving > 10 miles (as far as 150 miles) between winter and summer ranges. Most of the movements were northeast in the spring, and southwest in the fall. Pronghorn returned to the same area each summer, but not all pronghorn returned to their past winter ranges. Few (< 10%) fall migrations occurred between the population survey and the hunting season; therefore, during our years of study, the survey accurately reflected the distribution of pronghorn for the hunting season. Along with migration information, it is also important to identify pronghorn habitat to guide land management decisions, inform mitigation processes and identify limited resources for pronghorn. We evaluated the effect of vegetation type, ruggedness, and distance to nearest roads on summer and winter resource use for 50 GPS-collared, female adult pronghorn in North Dakota, 2005â€"2008 During both seasons, pronghorn selected open vegetation types in non-rugged habitat. Major roads were avoided in the summer and gravel roads were avoided during both seasons. Reduction of open vegetation, or road developments, in nonrugged areas where habitat is limited, might decrease the value of available pronghorn habitat.

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