Fish and Aquatic Species

Biological production represents the total amount of living material (biomass) that was produced during a defined period of time. This production is important because some of it is used for food and some is valued for recreation, it is a direct measure of total ecosystem processes, and it sustains biological diversity. Production is a measure of energy flow, and is therefore a natural currency for...

Impact of UMESC Science This research aims to estimate the fraction of mussels that are able to avoid short-term mortality during a water level drawdown by burrowing or moving horizontally into deeper water. Resource managers can use this critical information about mussel behavior and survival to make informed river management decisions.

Impact of UMESC Science The results of this study suggest that native mussels play an integral role in this ecosystem by sequestering large volumes of suspended materials that can be used by other benthic organisms. Managers now have critical data on population size, distribution, and relative health—these data are being used to guide habitat restoration activities to benefit native mussel...

In the past century about 20 mussel species have become extinct from the Upper Mississippi River (UMR) basin, and at least 28 species are state or federally listed. The species composition appears to have changed considerably from pre-European settlement times toward communities dominated by mussels that are tolerant of pollution and can utilize many different types of habitats. River managers...

Freshwater mussels are in serious global decline and urgently need protection and conservation. Declines in the abundance and diversity of North American mussels have been attributed to a wide array of human activities that cause pollution, water-quality degradation, and habitat destruction. Recent findings suggest that many mussel species are already living close to their upper thermal tolerances...

The spectaclecase mussel, Cumberlandia monodonta, was effectively listed as federally endangered in April 2012 (https://federalregister.gov/a/2012-5603). It is endemic to the Mississippi, Ohio and Missouri River basins and historically inhabited 44 streams in these basins (USFWS 2014). Currently, the species is known to inhabit 20 of the historical streams, five of which are represented by one or...

Invasive fishes are of considerable concern to aquatic resource managers. For example, the common carp (Cyprinus carpio), originally brought over from Eurasia sometime in the 1800s are now ubiquitous in U.S. waters. Although they have been around for over 100 years and have become part of U.S. culture, they are still highly detrimental to aquatic ecosystems and a method to eradicate and control of...

Populations of amphibians have been declining around the world (Stokstad 2004). The US Geological Survey is working to understand the extent and causes of such declines via the Amphibian Research and Monitoring Initiative (ARMI). We are conducting research in support of this program in the Midwest Region of ARMI. Our offices and laboratories are at the Upper Midwest Environmental Sciences Center...

Invertebrate communities provide food for several economically and ecologically important fish and waterbird species in coastal estuaries. Scientists at the WERC San Francisco Bay Estuary Field Station specialize in studying foraging ecology of waterbirds and fishes, general food web dynamics across estuaries, and the effects of habitat restoration and other factors on waterbird prey availability.

Adult sea lamprey abundance in Lake Erie increased during the past decade, exceeding pre-control levels and causing extensive mortality on some strains of stocked lake trout (Markham 2015). Control agents speculate that this increase may be due to an uncontrolled larval sea lamprey population in the St. Clair River because other known sources of larval sea lampreys are regularly treated with...

Introduced rainbow trout and brown trout are considered a threat to the endangered humpback chub in the Colorado River in Grand Canyon. These introduced species eat native fish, but impacts are difficult to assess because predation vulnerability depends on the physical conditions under which predation takes place. We studied how predation vulnerability of juvenile humpback chub changes in response...

Although it is not listed on the Federal Endangered Species list, there is considerable concern over northern leopard frog declines in western North America. It is listed as a “special concern” species by some state wildlife agencies (e.g., Arizona Game and Fish Department 1996) and declines have been reported in Arizona, Colorado, New Mexico, and other areas across the west. Leopard frogs have...