Conclusion
In this study, we applied deep learning to identify hybrids between Japanese and Chinese giant salamanders. Our results show that the head of giant salamanders is effective for classification. The use of Grad-CAM also revealed that the spot pattern is important for identifying the two species. Visual identification of hybrids has historically been restricted to specialists, but our approach could give a possibility for the public to identify hybrids. These results support the identification of hybrids, especially within the context of citizen science.
Acknowledgements
We are very grateful to the Hiroshima City Asa Zoological Park for their cooperation in our research on Japanese giant salamanders. Under permission from the Agency for Cultural Affairs, the Asa Zoological Park is researching and breeding the Japanese giant salamander, a nationally protected species. This work was supported by the Sasakawa Scientific Research Grant from The Japan Science Society.
Author contributions
Kosuke Takaya: Conceptualization, data analysis, interpretation, and preparation of the first original manuscript
Yuki Taguchi: Conceptualization, data collection, interpretation, and suggestions for the original manuscript
Takeshi Ise: Guided all steps of the analysis and manuscript preparation.
Competing interests
The authors declare no conflicts of interest associated with this manuscript.
Data availability statement
The code and models are both also archived at Zenodo.
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