Folder
ROOT
_ScienceBase Catalog
__US Fish and Wildlife Service (USFWS)
___Archive
____Pacific Region, Region 1
_____Pacific Lamprey Data Clearinghouse
______Genetics
_______eDNA
________non-Lamprey eDNA
Fisheries conservation requires accurate knowledge of species identities and distributions. Fisheries are typically assessed via capture-based sampling, but managers frequently are unable to conduct extensive surveys due to budgetary constraints. Sampling of environmental DNA (eDNA) released by fish is a potentially cost-effective approach that could improve species detection per unit effort. However, eDNA methods have not been widely adopted, in part because the cost and effort of eDNA versus traditional sampling are often unclear to managers. We compared the monetary costs and sampling effort required to assess the distribution of Brook Trout Salvelinus fontinalis in a Wisconsin watershed using both electrofishing...
Proper management of species relies on accurate assessment of their distributional range. When species are rare, monitoring techniques can fail to detect them. This is particularly true in aquatic environments where the underwater environment hides organisms from view. Recent work using DNA suspended in the water column, otherwise known as environmental DNA (eDNA), has indicated that such techniques have greater sensitivity than traditional techniques in lentic systems. In this thesis, I explore the potential use of eDNA as a monitoring tool in headwater stream systems, where currents are more likely to rapidly carry suspended DNA away from the source. In Chapter 1, I provide a brief overview of the use of eDNA...
Summary 1. In Rees et al. (2014b), we reviewed the current status of environmental DNA (eDNA) to monitor aquatic populations. Our aim was to focus on discussion of methodologies used, application of eDNA analysis as a survey tool in ecology, and to include some innovative ideas for using eDNA in conservation and management. 2. Roussel et al. (2015) claim that analysis of Rees et al. (2014b) and other publications highlights the downsides of the method, and they suggest that some conclusions should be toned down. Many of their arguments were covered in our original paper (Rees et al., 2014b); however, they make the point that modelling approaches should be encouraged, and we fully agree with this suggestion. 3. Roussel...
Accurate knowledge of the distribution of rare, indicator, or invasive species is required for conservation and management decisions. However, species monitoring done with conventional methods may have limitations, such as being laborious in terms of cost and time, and often requires invasive sampling of specimens. Environmental DNA (eDNA) has been identified as a molecular tool that could overcome these limitations, particularly in aquatic systems. Detection of rare and invasive amphibians and fish in lake and river systems has been effective, but few studies have targeted macroinvertebrates in aquatic systems. We expanded eDNA techniques to a broad taxonomic array of macroinvertebrate species in river and lake...
Summary 1. Using environmental DNA (eDNA) to detect aquatic macroorganisms is a new survey method with broad applicability. However, the origin, state and fate of aqueous macrobial eDNA – which collectively determine how well eDNA can serve as a proxy for directly observing organisms and how eDNA should be captured, purified and assayed – are poorly understood. 2. The size of aquatic particles provides clues about their origin, state and fate. We used sequential filtration size fractionation to measure the particle size distribution (PSD) of macrobial eDNA, specifically Common Carp (hereafter referred to as Carp) eDNA. We compared it to the PSDs of total eDNA (from all organisms) and suspended particle matter (SPM)....
Environmental DNA (eDNA) detection has emerged as a powerful tool for monitoring aquatic organisms, but much remains unknown about the dynamics of aquatic eDNA over a range of environmental conditions. DNA concentrations in streams and rivers will depend not only on the equilibrium between DNA entering the water and DNA leaving the system through degradation, but also on downstream transport. To improve understanding of the dynamics of eDNA concentration in lotic systems, we introduced caged trout into two fishless headwater streams and took eDNA samples at evenly spaced downstream intervals. This was repeated 18 times from mid-summer through autumn, over flows ranging from approximately 1–96 L/s. We used quantitative...
Environmental DNA (eDNA) monitoring approaches promise to greatly improve detection of rare, endangered, and invasive aquatic species. Although research has shown eDNA to be a sensitive monitoring tool, rigorous comparisons to traditional field sampling methods have not been fully explored. Few studies have specifically examined the application of eDNA within a statistical framework that explicitly allows for direct comparison between eDNA and traditional field sampling approaches while simultaneously accounting for imperfect detection of both methods. An eDNA approach was compared to traditional seining methods for determining site occupancy and relative abundance of endangered tidewater goby (Eucyclogobius newberryi)...
Abstract Environmental DNA (eDNA) from aquatic vertebrates has recently been used to estimate the presence of a species. We hypothesized that fish release DNA into the water at a rate commensurate with their biomass. Thus, the concentration of eDNA of a target species may be used to estimate the species biomass. We developed an eDNA method to estimate the biomass of common carp (Cyprinus carpio L.) using laboratory and field experiments. In the aquarium, the concentration of eDNA changed initially, but reached an equilibrium after 6 days. Temperature had no effect on eDNA concentrations in aquaria. The concentration of eDNA was positively correlated with carp biomass in both aquaria and experimental ponds. We used...
