How the goitered gazelle (Gazella subgutturosa) adapts to isolated island: from the perspective of habitat and food

Context Wild ungulates are an important component of natural ecosystems and one of the most important ecological groups of grassland ecosystems. The goitered gazelle (Gazella subgutturosa) is a species widely distributed in arid and semi-arid desert regions and is listed on the IUCN Red List (2016) as a threatened, vulnerable species at high risk for extinction in the wild. Goitered gazelle often lives in vast habitats; however, it is not yet clear how they adapt to isolated ‘islands’. Aims We selected an international nature reserve in the arid region of central Ningxia, China, as our study area, trying to understand how the goitered gazelle adapts to this microenvironment from the perspectives of habitat and diet. Methods We employed the optimized maximum entropy model and DNA metabarcoding to investigate the species’ suitable habitat distribution and feeding habits. Key results The results showed that the MaxEnt model performed well, with an area under curve value of 0.896 and a true skill statistic value of 0.704 for predicting the species distribution. Suitable habitats accounted for 80.9% of the total area of the reserve. Annual mean temperature, and elevation, together with the distance from water source were the critical factors that affected the goitered gazelle distribution range. Sequencing analysis indicated that among the 35 fecal samples collected, there were 18 plant families, and 21 genera annotated. The bulk food of goitered gazelle was Fabaceae and Rosaceae. Conclusions Water sources and altitude significantly influenced the distribution of the goitered gazelle. Trnl, as a DNA barcode, holds potential in the dietary analysis of goitered gazelles and can serve as a complement to traditional research methods. Implications This study confirmed the reliability of the optimized maximum entropy model for predicting suitable habitats at a small scale, and it is the first to apply DNA metabarcoding technology to the dietary analysis of the goitered gazelle. We also have more knowledge about how the goitered gazelle adapts to the isolated island habitat, laying the foundation for better protection of this species in the future.