Fish and Aquatic Species

The Herpetological Research Team focuses on issues related to conservation and management of amphibians and other aquatic and semi-aquatic species. Among our current studies are effects of invasive species, disease, and land use change on the dynamics of amphibian communities to inform conservation and management decision making.

Differentiating diploids from triploids at the earliest life stage possible allows for a more efficient use of resources including production time and rearing space. Thus, a reliable flow cytometric (FCM) method has been developed to discriminate triploids from diploids at the larval stage. In order to help simplify the process of differentiating triploids from diploids, we propose a simple...

Rivermouth ecosystems, or freshwater estuaries, are the focus of human and wildlife interactions with the Great Lakes. They are highly valued as the region’s urban, industrial, shipping and recreational centers; and home to recreational harbors, wildlife viewing and production, beaches and urban riverfronts. Rivermouths are also both the mixing zones where nutrients from upstream watersheds are...

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.