Back-Calculation of Fish Size in Diet Analysis of Piscivorous Predators: A New Index for the Alien Silurus glanis
Round 1
Reviewer 1 Report
A welcome topic, an original and useful approach from the Back-Calculation approach point of view, different from what others Back-Calculation Methods has been done so far. The article respects the rigors of a scientific paper.
The sections Abstract, Introduction, Material and Methods, Results, Conclusion and contain clear analyses, explanations, corelations and conclusion reflecting nature and inter- conditionalities.
Bibliographic resources are correctly mentioned throughout the article.
Reviewer 2 Report
In this work Renato et al. states the impact of invasive species Silurus glanis on the local ichthyofaunal diversity and, mainly, proposes a novel indicator using undigested ( focusing on vertebrae) prey parts by the Eurasian otter Lutra lutra.
The work is clear and well written and indeed adds value to the current literature, however a few details require clarification.
Line 70 Please state the methodology of electrofishing as well as the device used
Line 152 " they represented useful tools for species identification " It is a known fact, please use citation
Hopefully, in time, the K index will become one of the classic indicators. Good work, congratulation.
