Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Invasive lionfish detected in estuaries in the Northern Gulf of Mexico using environmental DNA.

Abstract

Invasive lionfish are considered to be one of the worst marine invaders primarily due to their threat as predators to native species. The distribution of lionfish across their invasive range has been fairly well characterized, but their presence within estuaries is largely unknown. While removal of invasive lionfish is the primary mode of managing the invasion, early detection in new locations could be valuable for documenting range expansion. Environmental DNA (eDNA) has become a useful tool to identify the presence of invasive species prior to establishment and may be especially valuable for systems that are challenging to survey. In this study, an environmental DNA assay was developed and successfully identified the presence of lionfish DNA in four riverine estuaries in the northern Gulf of Mexico. Detections were significantly higher in July but did not vary by location. Occupancy modeling shows that the assay is not exceptionally sensitive and may be underreporting the presence of lionfish, possibly due to the effect of salinity. The presence of invasive lionfish within estuaries could put native fish and invertebrates at risk, especially species that use these systems as nurseries. Ongoing monitoring using molecular methods may be useful in the management of invasive lionfish by providing early detection of fish moving into systems that neighbor known invaded regions.