Size does not matter: natural history and sexual dimorphism of the striped hog-nosed skunk (Carnivora, Mephitidae) in protected and anthropised landscapes of a Neotropical ecosystem

Abstract

Expanding the knowledge on natural history of Carnivores allows to understand mechanisms species developed for survival and improve decision making aiming conservation. Studies on eco-morphological aspects of skunks, as Conepatus amazonicus, are scarce and from small samples. We assessed roadkill individuals, faeces, camera trap records, and biometric data to describe the feeding ecology, activity period and morphology of skunks in agroecosystems and protected areas in the Brazilian Savanna. Invertebrates represented critical items in the diet in agroecosystems and protected areas, and due an intermediate niche breadth (0.545) skunks cannot be classified as specialists or generalists. Males and females have total niche overlap (0.94), and the diversity of items was not affected by proximity to urban centres. Animals develop their activities during the night, with 93% (n = 71) of records from sunset to sunrise. Males (2.56 kg) are 30% heavier than females (1.96 kg), suggesting sexual dimorphism for C. amazonicus t = -3.7151; d.f. = 29; P < 0.0001). Foot size and dentition were also larger in males, corroborating the sexual selection hypothesis. Behavioural and morphological adaptations favour predation on insects, prey of low physical resistance, that are also available in environments modified for agriculture. This is the first study to report sexual dimorphism in C. amazonicus. Our results fill a gap in the knowledge of a species that plays unique role in ecosystem function, suggesting skunks represent the primary small-sized omnivorous-insectivorous occupying the Savanna.