关键词: 豹猫, 机会主义捕食者, 高通量测序, 非损伤性取样, 食物组成, 生物多样性监测

Abstract

Aims: As the current apex predator in western Liaoning, the leopard cat (Prionailurus bengalensis) plays a crucial role in maintaining ecosystem stability. Elucidating its dietary characteristics and response mechanisms to environmental changes is of great significance for assessing regional biodiversity and ecosystem functions. This study aims to determine the vertebrate prey composition of leopard cats in this region and analyze the spatial heterogeneity of their diet across different habitats. 

Methods: Field surveys were conducted in three national nature reserves (Wuhuading, Qinglonghe, and Louzishan) and their surrounding areas in western Liaoning. A total of 199 suspected leopard cat fecal samples were collected. Species origin was verified using mitochondrial 16S rRNA molecular markers, confirming 110 samples as leopard cat. To ensure sampling independence, 57 samples were spatially screened for dietary analysis. We employed DNA metabarcoding technology combined with a self-designed leopard cat-specific blocking primer to systematically analyze the vertebrate prey composition and spatial variations. 

Results: (1) A total of 47 molecular operational taxonomic units (MOTUs) were identified, including 20 mammals, 22 birds, 1 amphibian, 2 reptiles, and 2 fish. Mammals, particularly Rodentia, were the core prey group. The Niviventer confucianus(FO = 92.98%, RRA = 26.78%), Tscherskia triton(FO = 66.67%, RRA = 24.58%), and Apodemus agrarius(FO = 98.25%, RRA = 7.86%) were the absolute dominant prey species. The Lepus tolai(FO = 50.88%, RRA = 11.45%) from Lagomorpha and the Phasianus colchicus(FO = 64.91%, RRA = 7.24%) from Galliformes were identified as important supplementary food resources. (2) The dietary composition exhibited significant spatial heterogeneity among different populations. The Wuhuading population showed strong dietary specialization, highly depending on forest-dwelling rodents. The Qinglonghe population reflected a significant "edge effect" with a high predation rate on the farmland species Tscherskia triton. The Louzishan population exhibited the widest trophic niche, with significantly higher utilization rates of birds and lagomorphs compared to the other two areas. 

Conclusion: Our results indicate that leopard cats in western Liaoning primarily prey on rodents, followed by lagomorphs and galliform birds. As typical opportunistic predators, leopard cats demonstrate high plasticity in foraging strategies, adjusting their diet according to local prey availability and habitat types. Furthermore, this study demonstrates that scat-based DNA metabarcoding is an effective tool for monitoring cryptic small vertebrate diversity, serving as a valuable complement to traditional biodiversity surveys.

Key words: leopard cat, opportunistic feeder, high-throughput sequencing, non-invasive sampling, diet composition, biodiversity monitoring