Few places in the world support three or more sympatric canid species. We investigated the mechanisms behind the spatial, temporal, habitat, and dietary partitioning within a guild of carnivores in the Banni grasslands in the arid northwest of India, in 2014-15. The region harbours four co-occurring canids: desert fox (Vulpes vulpes pusilla), Indian fox (Vulpes bengalensis), golden jackal (Canis aureus), and feral dog (Canis lupus familiaris). All four species are free-ranging and the latter two are human-subsidized to varying extents in the region. The landscape has been modified by the invasive bush Prosopis juliflora in the last three decades.
Camera traps were deployed across the landscape and habitat covariates were collected at each camera site to determine the occurrence of each species, in order to understand how they partition space, time, and habitat. To understand dietary partitioning, scat for all the wild canids was opportunistically collected near known dens and camera trap locations. Statistical models were used to estimate the influence of the habitat and environmental variables, as well as the presence of the other species, on the co-occurrence of a given species.
Results/Conclusions
The results indicate complex interactions between the study species. There appears to be noticeable spatial partitioning between desert foxes and the other canids, with jackals occurring in Prosopis-dominated habitats, while desert foxes occur in more open saline habitats with Suaeda fruticosa. The results of scat analysis for the wild canids indicate an overlap in the animal matter consumed but differences in plant matter consumption. As for temporal partitioning, both fox species were active at the same time, while none of the wild canids were active when dogs, predominantly diurnal, were active. Jackals were crepuscular as well as nocturnal, while both foxes were mostly nocturnal.
This study provides insights on how biotic interactions such as interference competition, along with habitat type and quality, and human presence affect the distribution and landscape use of a guild of sympatric carnivores. It has also resulted in essential baseline information on the occurrence and distribution patterns of multiple canids in a landscape that is human-dominated and is also modified by invasive plants, in addition to increasing our understanding of how human-subsidized canids affect other canids as competitors.