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University of Northern Iowa

Winter

Publication Year

Articles 1 - 2 of 2

Full-Text Articles in Science and Mathematics Education

Weather Factors Influencing Winter Roosts Of American Crows In Central Iowa, Joshua D. Obrecht, Stephen J. Dinsmore Jan 2007

Weather Factors Influencing Winter Roosts Of American Crows In Central Iowa, Joshua D. Obrecht, Stephen J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

We investigated the effects of season and weather on the winter roosting behavior of American Crows (Corvus brachyrhynchos) in central Iowa from January through March 2006. The peak number of birds recorded at a roost in Ames, Story County was 9,000+ in early February, and the number of individuals entering the roost decreased through February and March. Crows tended to enter the roost later in the day as winter neared completion. High wind speed and low light intensity caused individual to enter the roost earlier in the day. Temperature did not affect arrival time of crows. Wind speed, light intensity, …


Winter Bird Use Of Conservation Reserve Program Fields Harvested For Biomass, Les D. Murray, Louis B. Best Jan 2006

Winter Bird Use Of Conservation Reserve Program Fields Harvested For Biomass, Les D. Murray, Louis B. Best

Journal of the Iowa Academy of Science: JIAS

As Conservation Reserve Program (CRP) contracts expire, many fields may be returned to agricultural production. Growing switchgrass (Panicum virgatum) as a biomass fuel is an alternative to returning fields to rowcrops. CRP fields provide winter cover for birds, but the harvest of biomass would remove most of the cover and affect bird use of the fields. We estimated winter bird abundances in nonharvested, total-harvested, and partially (strip) harvested switchgrass fields in southern Iowa. Song sparrows (Melospiza melodia) were observed only in strip-harvested fields and ring-necked pheasants (Phasianus colchicus) were observed only in nonharvested fields and uncut areas of strip-harvested fields. …