By Stephen Jones and Ruth Carol Cushman, Special To The Daily Camera Heavy October and November snows, along with frigid temperatures in the Northern Plains, have contributed to a modest influx of ferruginous and rough-legged hawks into Boulder County. Throughout November, we saw several of these large grassland hawks hunting around Lagerman Reservoir, Boulder Reservoir and in the grasslands north of Rocky Flats. During the 1980s and 1990s, wintering ferruginous and rough-legged hawks were considered fairly common on the plains of Boulder County.