Identifying spawning sites and other critical habitat in lotic systems using eDNA “snapshots”: a case study using the sea lamprey Petromyzon marinus L.

Many aquatic species of conservation concern exist at low densities and are inherently difficult to detect or monitor using conventional methods. However, the introduction of environmental (e)DNA has recently transformed our ability to detect these species and enables effective deployment of limited conservation resources. Identifying areas for breeding, as well as the ecological distribution of a species are vital to the survival or recovery of a conservation species (i.e. critical habitat). In many species, spawning events are associated with a higher relative abundance of DNA released within an aquatic system (i.e. gametes, skin cells etc.), making this the ideal time to monitor these species using eDNA techniques. This study aims to examine whether a ‘snapshot’ eDNA sampling approach (i.e. samples taken at fixed points in chronological time) could reveal areas of critical habitat including spawning sites for our target species Petromyzon marinus. We utilised a species-specific qPCR ...