Spatial and behavioral changes by red foxes (Vulpes vulpes) in response to artificial territory intrusion

Abstract

Urine marking is thought to play a pivotal role in territory demarcation by red foxes ( Vulpes vulpes (L., 1758)), but little is known about how individuals respond to alien scent marks, and whether there are sex-related differences in territorial defense. We radio-tracked dominant male and female urban foxes before and after synthetic fox urine was applied to approximately a third of their territories and compared spatial and behavioral reactions both before and after scent application and with foxes on territories where no urine was applied. Home-range boundaries of male foxes shifted towards the scent-marked area, but this change did not affect the total territory size. Larger males shifted their home ranges to a greater degree than small males. Scent application did not affect total activity, but males spent more time in the scent-marked area. Behaviors such as distance moved per night and speed of movement did not differ before and after application, but foxes searched a greater percentage of their home range each night following scent marking. Females showed no significant spatial or behavioral response to the synthetic scent marks. Overall, responses of foxes to synthetic scent marks were male-biased and related to changes in space use rather than movement behaviors.