European cave salamanders of the genus Hydromantes are a group of eight species endemic to Italy and south-eastern France. Knowledge on the trophic niche of European Hydromantes is poor, and the few available studies only partially investigate their feeding habits. We performed an in-depth study on the trophic niche of the Ambrosi’s cave salamander (H. ambrosii), assessing the potential divergences among three different populations. All the populations had a similar diet composition, showing a wider trophic niche in fall compared to spring. In only one population, “true specialists” were present; however, in all three populations, generalist individuals always represented the larger proportion. Interspecific and intraspecific competition did not play an important role in determining individual dietary specialisation in H. ambrosii; contrarily, the characteristics of the surrounding environment seemed to be an important factor. The best body conditions were observed in the population located in the site where the non-arboreal vegetation cover was the highest. Besides providing new information on the trophic niche of H. ambrosii, we here showed that studies encompassing both intrinsic and extrinsic factors at the population level are needed to fully understand the trophic dynamics occurring among European cave salamanders.

中文翻译：

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相同的饮食，不同的策略：安布罗西洞穴Sal（Hydromantes ambrosii）的三个种群的个体进食习惯的变异性

欧洲水Hydro类的洞穴cave是意大利和法国东南部特有的八种物种。关于欧洲水man的营养小生境的知识很贫乏，很少有可用的研究仅部分调查它们的摄食习惯。我们对安布罗西洞穴sal（H. ambrosii）的营养生态位进行了深入研究），评估三个不同人群之间的潜在差异。所有人群的饮食组成相似，与春季相比，秋季的营养生态位更广。只有一个人口中存在“真正的专家”。但是，在所有三个人口中，通才个体始终占较大比例。种间和种内竞争在确定汉布鲁氏菌的个体饮食专业性中并不发挥重要作用; 相反，周围环境的特征似乎是一个重要因素。在非乔木植被覆盖最高的地点的人群中观察到最佳的身体状况。除了提供有关H. ambrosii的营养小生境的新信息，我们在这里表明，需要在人口层次上同时包含内在和外在因素的研究，才能充分了解欧洲穴居among之间发生的营养动力学。