eDNA reveals spatial differences in species composition of protected rockfishes

Area of Science:

• Marine Biology
• Conservation Genetics
• Environmental DNA (eDNA) analysis

Background:

• Detecting rare and elusive marine species is challenging.
• Environmental DNA (eDNA) offers a promising approach to increase data availability for monitoring and management.
• The diverse rockfish genus Sebastes presents a model system for testing eDNA utility.

Purpose of the Study:

• To develop and validate a novel eDNA metabarcoding assay for identifying rockfish species.
• To assess the effectiveness of eDNA for detecting rare and difficult-to-observe rockfish in Puget Sound.
• To evaluate the impact of sampling location on eDNA-based species detection.

Main Methods:

• Identified a phylogenetically informative gene region for eDNA metabarcoding.
• Developed an assay to uniquely identify 93 out of 109 described Sebastes species.
• Collected and analyzed eDNA from field samples using three different sampling platforms in Puget Sound.

Main Results:

• The developed eDNA assay successfully identified a significant portion of rockfish species.
• Species detection rates and diversity varied substantially based on sample collection location (distance from seafloor).
• Findings suggest that sampling location significantly influences eDNA detection, likely due to species-specific habitat preferences.

Conclusions:

• eDNA metabarcoding is a powerful tool for monitoring diverse and rare rockfish populations.
• The developed assay is valuable for rockfish monitoring in Puget Sound and the broader North Pacific.
• eDNA data significantly aids in the conservation and management of rare and difficult-to-distinguish marine species.