Diet Switching and Interspecific Competition in Sympatric Steppe Ungulates Under Seasonal Resource Variability

TL;DR

This study explores how Kiang and Tibetan Gazelle share and compete for food resources in a seasonal environment on the Tibetan Plateau.

Contribution

The study reveals how dietary flexibility and niche partitioning reduce competition between sympatric ungulates in seasonal habitats.

Findings

Kiang and Tibetan Gazelle show high dietary overlap but differ in forage species use.

Tibetan Gazelle exhibits greater dietary flexibility and seasonal shifts in diet.

Both species mitigate competition through differential forage use and individual dietary variation.

Abstract

Understanding the mechanisms of competition and coexistence among sympatric species is crucial for deepening our understanding of interspecific interactions and informing the conservation of rare and endangered wildlife. In this study, we utilized DNA macro‐barcoding technology to analyze the seasonal dietary habits of Kiang (
Equus kiang
) and Tibetan Gazelle (
Procapra picticaudata
) in Shiqu County, Sichuan Province, aiming to investigate their resource partitioning strategies and potential competition for limited forage resources. The results showed that Kiang mainly consumed Cyperaceae and Polygonaceae in both seasons, while Tibetan Gazelle fed on Polygonaceae and Rosaceae in the warm season and shifted to Ephedraceae in the cold season. Both species exhibited significant seasonal differences in dietary composition, with Tibetan Gazelle showing greater individual variation and seasonal shifts. In addition, their dietary niche was broader in the warm season, and overlap remained high, with indices of 0.89 and 0.87 in the warm and cold seasons, respectively. The results indicate that although Kiang and Tibetan Gazelle exhibit partial dietary overlap, they mitigate interspecific competition and achieve sympatric coexistence through differential use of dominant forage species, adjustments in dietary proportions, and individual dietary flexibility; notably, Tibetan gazelles exhibit stronger ecological adaptability. This study highlights a competition–coexistence dynamic along the trophic niche axis in typical plateau ungulates, providing insights for effective conservation strategies and biodiversity conservation in plateau regions.

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