Utilizing Environmental DNA Metabarcoding to Assess Fish-Based Food Resources in Key Foraging Areas of the Black...

The Black Stork (Ciconia nigra) is a widely distributed yet scarce wading bird, predominantly piscivorous, and is classified as a National First-Class Key Protected Wildlife Species in China. Effective conservation strategies necessitate the monitoring of its food resources. During the migration period of black storks, this study utilized environmental DNA (eDNA) metabarcoding to assess ichthyological resources within the water bodies of key foraging areas, specifically Zhanghe Canyon National Wetland Park and Qixi River National Wetland Park, Anyang City, Henan Province, China. The findings revealed a diverse range of fish species, including some not previously documented locally, with no significant differences in species composition between the two sites. The results suggest that the primary fish resources in the foraging habitats of black storks are species from the orders Siluriformes, Cypriniformes, and Perciformes. To address the risk of false detections inherent to eDNA technology, we implemented a two-step filtering method, as detailed and discussed in the main text. Based on these findings, we recommend that local governments integrate dynamic monitoring of the identified fish resources into routine conservation planning for black storks and its habitats, thereby ensuring the stability and sustainability of this essential food resource.