U.S. Department of Agriculture: Animal and Plant Health Inspection Service
United States Department of Agriculture Wildlife Services: Staff Publications
Document Type
Article
Date of this Version
October 2004
Abstract
Over the past century, the amount of mixed-grass prairie in North Dakota has diminished with a concomitant increase in land used for crop production. Consequently, the diversity of habitat available for migrant birds has decreased, and birds are now limited to choosing habitats that are uncharacteristic of those used during other times of the year. Because of the extensive agricultural production in this region, the value of harvested crop fields to spring-migrating birds was studied by examining avian habitat use in harvested fields to determine differences in bird use among these habitats. In the spring of 2003, 60 harvested fields were surveyed 130 sunflower (oil or confection) and 30 non-sunflower (soybean, small grain, corn, or sorghum)] for bird abundance to determine what, if any, difference in bud use could be detected among the crop types available to migrating birds as stopover sites. We counted 10,200 birds constituting 33 different species throughout the study period. Homed larks (Eremophila alpestris) and Iapland longspurs (Calcarius lapponicus) were seen in greatest numbers. Overall bird abundance was greatest in sunflower fields compared to non-sunflower fields. Due to the great abundance of cropland in this region, harvested crop fields may provide a good source of forage and stopover habitat.
Comments
Published by Proc. 16th International Sunflower Conference, Fargo, ND