Aquatic Ecosystem Health

Bighead carp and silver carp (collectively known as bigheaded carps) first escaped to the Mississippi River Basin in the 1970s and by 1989 had invaded the Tennessee and Cumberland Rivers. The species threaten the economies and ecosystems for these rivers and are currently spreading upriver. USGS scientists are developing population-level models to help guide and inform control strategies and...

The Obed Wild and Scenic River, located on the Cumberland Plateau, is in a region where major declines and mass mortality of mussels have been observed. The Wild and Scenic River contains designated critical habitat for the federally endangered endemic Tennessee Bean ( Venustaconcha trabalis; aka Purple Bean). Water quality and habitat conditions in the Obed are critical factors for recovery of...

Previous studies and experience have demonstrated that some locks and dams operate as bottlenecks or pinch points for invasive carp populations and range expansion because of unique hydraulic conditions and operations at these dams. As compared to dams without these unique conditions, pinch-point dams restrict upstream fish passage to the lock chamber and result in limited (but not zero) upstream...

The Mississippi River is of global importance to persons and to the wildlife that live on and migrate along the river corridor. Data collected and processed by the Long-Term Resource Monitoring (LTRM) element of the Upper Mississippi River Restoration (UMRR) Program serves to help us understand, restore, and protect this remarkable ecosystem. The LTRM has collected aquatic and floodplain...

Shallow lakes are a key resource for waterfowl species, so protecting and restoring these areas is of great importance to managing their populations. This study evaluated the effectiveness of management practices on shallow lakes and their influence on waterbird populations that depend on them. Researchers found that lake management actions increased the abundance of submerged aquatic vegetation...

Cyanobacteria (a.k.a. blue-green algae) are photosynthetic bacteria that occur in a wide array of terrestrial and aquatic habitats. In freshwaters, cyanobacteria sometimes form extremely dense populations that are termed blooms or harmful algal blooms (HABs). When forming blooms, cyanobacteria cause a variety of environmental issues, but one of the most important is the production of compounds (i...

Harmful algae blooms can produce cyanotoxins that are harmful to humans, pets, livestock, and ecosystem health. Harmful algae blooms are a frequent occurrence in the Great Lakes, particularly in Lake Erie and Lake Michigan at the mouths of the Maumee and Fox Rivers and are partially caused by an excess of nutrients such as nitrogen and phosphorous in the water column.

The Snuffbox mussel ( Epioblasma triquetra) was a historically widespread species occurring in 210 lakes and streams in the United States and Canada; however, the range has declined by 62% and reduced to 79 lakes and streams. Existing populations are small and isolated, increasing the risk of species extinction. These factors prompted the listing of Snuffbox as federally endangered in 2012...

Bighead carp ( Hypophthalmichthys nobilis) and silver carp ( Hypophthalmichthys molitrix) are invasive carp species within the Mississippi River basin. In the early-1970s these species escaped from ponds where people introduced them to control algae (ICRCC). Invasive carp cause ecological and economic damage by outcompeting native species and disrupting native food webs. Stopping the spread of...

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...

Michigan and Ohio Department of Natural Resources along with the U.S. Geological Survey (USGS) Columbia Environmental Research Center (CERC) and USGS Upper Midwest Environmental Science Center (UMESC) are planning field studies to attract Grass Carp using formulated baits and algae attractants. These baits are intended to increase the density of Grass Carp in specified areas for capture and...

Currently, the only U.S. Environmental Protection Agency (USEPA) registered pesticide for resource managers to control populations of Invasive Carp (e.g., Bighead Carp, Hypophthalmichthys nobilis) are rotenone (Prenfish Fish Toxicant; EPA Reg. No. 89459-85) and Carbon Dioxide – Carp (EPA Reg. No. 6704-95). An alternative to rotenone and Carbon Dioxide – Carp, antimycin-A (ANT-A), is desired by...