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bioRxiv · 10.1101/2024.04.04.588082

Three's Company: Anthropogenic factors shape co-occurrence in a meso-carnivore community in a semi-arid shared landscape of western India

Abstract

O_LIHuman modification of natural landscapes accelerates species extinctions, promotes biological invasions, coerce range shifts, and restructure biotic communities. Mammalian meso-carnivores, considered sentinels of human-use landscapes, may experience increased mortality through road collisions and interactions with free-ranging dogs. Yet they may also benefit through resource subsidisation and decreased competition with larger carnivores. Our understanding of meso-carnivore community structure in modified ecosystems remain severely limited. C_LIO_LIWe examined a meso-carnivore community comprising golden jackal Canis aureus, jungle cat Felis chaus, Indian fox Vulpes bengalensis and desert cat Felis lybica ornata in a semi-arid landscape of Kachchh, western India. First, we mapped their potential habitats and the extent of fragmentation as a measure of vulnerability. We then assessed spatial, temporal and fine-scale spatio-temporal co-occurrence and responses to anthropogenic influences in the meso-carnivore community. We used a combination of camera-trapping and indirect sign surveys within an occupancy modelling framework to generate insights on species space-use and interactions. C_LIO_LIThe most fragmented habitat, open savanna, was positively associated with the occurrence of golden jackal, Indian fox and desert cat. Golden jackal spatially co-occurred with jungle cat and Indian fox with desert cat. Indian fox and desert cat showed spatial avoidance of golden jackal and jungle cat. Meso-carnivores did not show any spatial responses to free-ranging dogs, but showed varied responses to human infrastructure, i.e., settlements, roads and wind turbines, generally co-occurring less with each other in areas with high anthropogenic influence. C_LIO_LISpatially co-occurring meso-carnivores also overlapped substantially in the temporal dimension. Golden jackal and jungle cat showed high temporal overlap with free-ranging dogs, while Indian fox and desert cat appeared to avoid them. Temporally overlapping species generally showed fine-scale spatio-temporal aggregation. C_LIO_LIOur results reveal species-specific responses to anthropogenic factors in the meso-carnivore community, often increasing overlap across space and time in a resource restricted landscape. Future loss of native savanna habitats and an increasing human footprint can elicit competition driven loss of sensitive species leading to homogenisation of the meso-carnivore community. Our findings highlight the importance of considering species-specific responses as well the complex interplay amongst species to conserve multi-carnivore systems across shared, resource-constrained landscapes. C_LI

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BibTeXRIS

Ganguly, D.. 2024-04-06. Three's Company: Anthropogenic factors shape co-occurrence in a meso-carnivore community in a semi-arid shared landscape of western India. https://doi.org/10.1101/2024.04.04.588082

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