Gray Fox (Urocyon cinereoargenteus)
Interactions and Spatial Relationships
ResultsGray foxes exhibited variable home range overlap depending on sex. We detected home range overlap among neighboring males, but only 1 male shared large portions of a home range with another male. Home range overlap for females was variable, as our data suggest that some females shared home ranges during breeding-denning, whereas neighboring females exhibited minimal overlap. Suspected pairs exhibited greater overlap (57%) compared to neighboring males and females (22%).
Core area overlap between males was minimal; however, we documented core area overlap for females that shared portions of home ranges. No core area overlap between neighboring females was documented. Suspected pairs exhibited greater core area overlap (28%) compared to neighboring males and females (1%). Seasonally, home range overlap for neighboring males was least during fall-winter (5%), but similar during breeding-denning (28%) and fall-winter (27%). Neighboring females exhibited greatest overlap during breeding-denning. For males and females with overlapping home ranges or suspected of sharing home ranges, overlap was similar during all seasons. Core area overlap for neighboring males was minimal during all seasons. Neighboring females exhibited greatest overlap during breeding-denning. For males and females, core area overlap was similar during all seasons.
We documented 12 instances of males and females traveling together through their home range. Given that sharing of home ranges occurred in these instances, these findings suggest the formation of pair bonds between these individuals. We monitored 16 gray foxes that shared home ranges and frequently moved together within home ranges and core areas. We documented 2 instances of 3 foxes who simultaneously traveled through shared regions of home ranges.
SummaryFrequent overlap in home ranges reported in gray fox studies suggests minimal territoriality among gray foxes. However, these studies did not attempt to associate kinship or pair bonding to observed overlap. Contrastingly, neighboring gray foxes on TWMA and GP maintained nearly exclusive core areas and frequently exhibited minimal home range overlap. This suggests some degree of territoriality in spatial use patterns of gray foxes on TWMA and GP. Previous research in southern Mississippi reported that territoriality among family groups or pairs was evident. The sharing of home ranges during breeding-denning and whelping-pup rearing by males and females suggests that pair bonding existed on TWMA and GP. Further, the simultaneous movements of foxes sharing home ranges indicate that these individuals frequently traveled together throughout shared areas and provides further evidence that pair bonding was prevalent. Likewise, the maintenance of nearly exclusive home ranges by neighboring foxes, coupled with no observed associations between neighboring same-sex foxes within 150 m, suggests territoriality and a mutual avoidance reaction among neighboring adults.
Management Implications Previous studies have suggested that territories established by gray fox could potentially be a useful measure of population density, assuming that a maximum of 2 adult foxes inhabit the same range. Our data tend to support contentions that placement of territories and boundary overlap may provide a useful index of density, as home ranges and core areas were nearly exclusive between neighboring individuals. However, the sharing of ranges by at least 3 foxes on several occasions in our study indicates that territories may at best provide measures of minimum density.