eDNA

Environmental DNA (eDNA) and related molecular methods are important tools for helping to detect and monitor invasive carp presence in the Mississippi River and Great Lakes basins. The use of eDNA has become a common method for detecting presence of invasive carp in areas of low density and uncertain presence. Furthermore, eDNA can be used to identify activities such as spawning. However, an eDNA...

We aim to develop control tools for eliminating invasive carps (silver carp – Hypophthalmichthys molitrix, bighead carp – H. nobilis, grass carp – Ctenopharyngodon idella, and black carp – Mylopharyngodon piceus) that use natural gene regulation mechanisms (RNA-induced gene silencing; RNA interference; RNAi) to be species-specific without non-target effects. Invasive carps cause substantial...

Researchers and managers have documented spawning by Grass Carp ( Ctenopharyngodon idella) in three tributaries of Lake Erie, with additional rivers potentially providing suitable spawning habitat. Spawning events can be targeted by managers to disrupt reproduction and remove aggregating fish. Prior research has identified the temperature and streamflow conditions that can help predict spawning...

Environmental DNA (eDNA) is organismal DNA that can be found in the environment. eDNA originates from cellular material shed by organisms (e.g., skin, hair, saliva, or feces) into aquatic and terrestrial environments. Researchers sample the air, soil, water or other areas to track or detect invasive, endangered, or rare species.

R is a free software that is used to run statistical analyses and models as well as create figures such as graphs and maps that can be used to display the data collected. While using this software researchers can also use downloadable packages that increase the number of analyses and models they can perform. Statisticians and researchers collaborate to create new packages that can be used by other...

Silver carp ( Hypophthalmichthys molirix) and bighead carp ( H. nobilis), commonly call bigheaded carp, are native to portions of Asia and were introduced to North America in aquaculture farms and sewage treatment ponds to control algae and plant growth. Bigheaded carp escaped from their intended locations and have an adverse effect on the ecosystem functions and the economic value of the...

Occupancy models are used by researchers to estimate the true occupancy of a species and accounts for imperfect detection of organisms in a study. Researchers will visit sampling sites to collect species detection data (e.g., species count). Occupancy models can predict the detection probability (probability of finding a species at a specific time and site) and occupancy (probability a species...

Presence-absence surveys are commonly used to estimate the spatial distribution of a species. However, during a field survey some organisms, especially rare or elusive species, can be missed; increasing the chance of error in the data collected. To combat the potential error, researchers will regularly visit sites and collect more data that will later be analyzed using occupancy models. Occupancy...

Scientists from six USGS science centers are collaborating with USDA, university, and Tribal partners, and Department of the Interior land managers, to assess the status of pollinator communities and the distribution of species of conservation concern using environmental DNA. These methods will be used to improve assessments of habitat quality and pollinator responses to restoration, including...

Molecular tools have garnered a lot of interest in natural resource management, particularly in biosurveillance. Filling gaps in monitoring, characterizing, communicating molecular approaches, and easily accessible information will help realize the potential of molecular tools. The Resource Manager's eDNA Toolbox is a series of web pages where managers can assess the available approaches, markers...

The USGS has developed the Rapid environmental (e)DNA Assessment and Deployment Initiative & Network (READI-Net) to accelerate the implementation of environmental DNA (eDNA) analysis as a best practice for the early detection of aquatic biological threats. READI-Net provides tools and a strategy to collect and deliver early detection data for natural resource managers and public health protection...

A team of USGS scientists is currently working with the MDNR, ODNR, USFWS, and academic institutions to evaluate the use of grass carp baits and attractants as a tool for resource managers. The science team aims to integrate the use of baits and attractants to increase aggregation of grass carp near targeted capture sites to enhance the multi-jurisdictional removal program associated with the Lake...