Fish survey limitations based on eDNA methods
Although the eDNA method has had a significant impact on the field of ecology, it faces some limitations as a developing science (Goldberg et al., 2016). One area of contention is whether the number of sequences obtained through eDNA analysis can be used as a proxy for the number of species identified in traditional surveys (Deiner et al., 2016; Zhang et al., 2022). This is a crucial consideration because the accuracy of the eDNA data relies on this assumption.
Another challenge is the reliability and accuracy of the species comparison databases used in eDNA studies. The credibility of the new records generated using this method is directly related to the quality of the database. However, the eDNA method alone cannot verify the accuracy of this database, which can affect the scientific rigor and reliability of the results.
Finally, there is the issue of whether eDNA results accurately reflect the fish species present at the sample site. DNA can originate from organisms located several kilometers away, which can lead to erroneous results (Deiner et al., 2016). This raises concerns about the representativeness of the eDNA data and underscores the importance of careful sampling.