Seasonal Variations in the Foraging Strategies of Plateau Pikas (Ochotona curzoniae)

This study investigates the foraging habits and dietary niche characteristics of plateau pikas (Ochotona curzoniae) by analyzing differences between the cold and warm seasons using stable isotope analysis of carbon and nitrogen in liver, muscle, and fur organs. The results indicated that in the cold season, the plant species incorporated into different organs were more diverse than in the warm season, with varying contribution rates for each plant species. Potentilla anserina made the most significant contribution to the plateau pika’s diet during the cold season, while Kobresia humilis had the highest contribution in the warm season. The trophic niche width of liver and muscle organs was broader in the cold season compared to the warm season, while the trophic niche width of the fur organ was narrower in the cold season. Additionally, long-term dietary information derived from muscle and fur organs showed a wider niche breadth compared to short-term dietary information obtained from the liver organ. Across both seasons, organ niche overlap was highest in fur, followed by muscle, and lowest in the liver. In conclusion, short-term food source information (derived from the liver organ) indicated fewer food types and a smaller niche breadth. In contrast, long-term food source information (obtained from muscle and fur organs) included a greater variety of food types and a larger niche breadth. Additionally, niche overlap was more pronounced on the long-term scale compared to the short-term scale. These findings highlight the adaptive feeding strategies of plateau pikas in response to varying seasonal food availability and the ecological importance of their dietary flexibility in maintaining energy balance in challenging environments.