Response to Koford: Red Squirrels and Supplemental Feeding

Koford (1992) suggested that the increase in red squirrel ( Tamiasciurus hudsonicus ) populations in response to supplemental food may have reflected an increase or extension of movements of squirrels onto food-supplemented areas. However, deletion of transient squirrels (those captured only once or twice) from the analysis did not affect the 3–4 times greater number of squirrels on supplemented than control areas. Klenner (1991; unpublished) reported that behavioral observations indicated good agreement between capture frequency and territorial status of squirrels captured >2 times, and these animals were considered residents. Radiotelemetry measurements of territory size and behavior indicated that supplemental food decreased time spent away from territories by squirrels and increased movements through, and proportion of time spent defending territories. Average territory sizes in the presence of supplemental food, based on telemetry and direct observations, ranged from 0.15 to 0.29 ha, which were similar values to those calculated for Sullivan's (1990) study by Koford (1992).