Muséum National d'Histoire Naturelle, Station Marine de Concarneau, Concarneau, France.
Institut de Systématique, Évolution, Biodiversité, Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, Station Marine de Concarneau, Concarneau, France.
J Fish Biol. 2020 Aug;97(2):515-526. doi: 10.1111/jfb.14407. Epub 2020 Jun 21.
Knowledge of skate ecology must be improved to ensure their effective protection. This study represents the first description of diet composition for one of the largest European rajid, the blue skate Dipturus cf. flossada. A total of 346 specimens collected in the Celtic Sea from 2012 to 2015 were analysed for their gut content, with respect to individual total length, maturity stage and sex. Overall, the blue skate diet mainly consisted of shrimps and prawns, crabs and teleost fishes. Nonmetric multidimensional scaling and ANOSIM analyses revealed major ontogenetic shifts in the feeding strategy that were related to size and maturity, but not to sex. Shrimps and prawns, mostly composed of Crangon allmanni, dominated the diet of small and immature individuals, while mod-size skate primarily preyed on crabs. The prevalence of crustaceans decreased with size and maturity, and was gradually replaced by teleost fishes in large mature individuals. A concomitant increase of the trophic level with size revealed that large blue skate become a top predator within the ecosystem. These results highlight the need to include ontogenetic changes in the diet description. As individuals grow and mature, blue skates can play a fundamental role in the structure of the Celtic Sea food web.
必须提高对鳐鱼生态学的认识，以确保对其进行有效的保护。本研究首次描述了欧洲最大的鳐鱼之一——蓝鳐 Dipturus cf. flossada 的食性组成。2012 年至 2015 年期间，在凯尔特海共采集了 346 个样本，根据个体全长、成熟阶段和性别对其肠道内容物进行了分析。总的来说，蓝鳐的饮食主要由虾、蟹和硬骨鱼组成。非度量多维尺度分析和 ANOSIM 分析表明，摄食策略存在主要的发育变化，与大小和成熟度有关，而与性别无关。虾和对虾（主要由 Allmanni 虾组成）主要是小的和未成熟个体的食物来源，而中型大小的鳐鱼主要捕食蟹类。甲壳类动物的丰度随大小和成熟度而减少，并逐渐被大型成熟个体的硬骨鱼所取代。随着大小的增加，营养水平的协同增加表明，大型蓝鳐成为生态系统中的顶级掠食者。这些结果强调了在食性描述中纳入发育变化的必要性。随着个体的生长和成熟，蓝鳐在凯尔特海食物网的结构中可以发挥重要作用。
