Fish and Aquatic Species

Widespread shale oil and gas (unconventional oil and gas, UOG) has only recently begun and many gaps in our knowledge of its potential effects to freshwaters exist.

Early detection systems for aquatic nuisance species have been improved by the advancement of polymerase chain reactions that amplify DNA sequences for decoding.

Small streams in forests are likely to see dramatic shifts as global climate change influences air temperature and rain patterns. We have already seen warmer stream temperatures as air temperatures increase in summer in the Northeastern US. The intensity and duration of floods and droughts are also expected to magnify as future rain patterns shift. This project will evaluate how stream temperature...

We are working closely with multiple partners to provide updated information, model potential outcomes, and identify key uncertainties relevant to amphibian and reptile species proposed for listing in the northeast US. We also provide timely science to partners to assist in recovery of listed species, which may involve field research, data analysis, or decision support.

USGS scientists are collaborating with the Maryland Department of Natural Resources (MDDNR) to develop and evaluate a genetic assay for blue catfish fish diets that will allow us to design a cost-effective monitoring program for determining the diet of wild fish.

These systems are characterized as 4th order and larger nontidal riverine systems, which includes many of the intermediate and larger size rivers, such as the Penobscot, Connecticut, Hudson, Delaware, and Susquehanna Rivers and their larger tributaries of the northeastern U.S. Fish passage, thermal stress, and ecological flows are likely important issues in these systems. Fish health issues and...

Disease may be caused by infectious agents, nutritional imbalances, physiological or genetically-based abnormalities, and suboptimal environmental conditions, acting either alone or in combination with other factors. In many instances, environmental stressors may merge forces with an infectious agent or some other non-infectious factor to produce or exacerbate a state of disease. By studying...

Striped bass ( Morone saxatilis ) displaying ulcerative skin lesions and chronic wasting, both typical clinical signs of mycobacteriosis, a bacterial disease that is problematic among many types of fishes around the world.

Whirling disease, caused by the myxosporean parasite Myxobolus cerebralis was identified as an emerging pathogen of trout in the intermountain west region of the U.S. in the early 1990’s. Investigators here worked collaboratively with others to further our understanding of this disease and its impacts on trout and other salmonid fishes.