Fisheries

Electrofishing in Ridley Creek

The Patrick Center Fisheries Section has expertise in stream, riverine and estuarine fish ecology, environmental impact assessment, biomonitoring, collection and identification of fishes (including ichthyoplankton), habitat and fisheries restoration, fisheries science, and analysis of fish contamination.

The excellent facilities of the Fisheries Section permit intensive and comprehensive scientific evaluations of aquatic systems and foster quality scientific investigation of dynamics of both lentic and lotic systems.

Staff

Richard J. Horwitz, Ph.D.

Section Leader and Ruth Patrick Chair in Environmental Science

Dr. Horwitz has over 30 years experience with the collection, identification and analysis of fish specimens from throughout the United States and other parts of the world (e.g., Canada, Central and South America, Nepal, Africa), statistical analysis of ecological data, and analysis of relationships between disturbance and fish communities. His expertise is in reproductive ecology, life history and distribution of freshwater fishes; effects of land use, habitat structure and hydrology on population dynamics and species composition in aquatic systems; ecological modeling and biometry; anthropogenic contaminants in fishes.

Paul F. Overbeck

Mr. Paul F. Overbeck has over 20 years experience in field collection, identification, and analysis (including otolith‑based age and growth measures) of freshwater and marine specimens from throughout the United States.

David Keller

David Keller has experience with invasive species, including the flathead catfish and the northern snakehead, and is conducting research on the native white catfish.

Expertise

The Patrick Center Fisheries Section has expertise in stream, riverine and estuarine fish ecology, environmental impact assessment, biomonitoring, collection and identification of fishes (including ichthyoplankton), habitat and fisheries restoration, fisheries science, and analysis of fish contamination. Our fisheries scientists work in aquatic systems throughout the United States and have experience working in other parts of the world including Canada, Central and South America, Nepal, and Africa. We maintain extensive fisheries databases that include long-term, continuous assessment data from projects that have been ongoing for over 50 years. These long-term databases, collections of the Fish Department of the Academy of Natural Sciences and other data sources have been used to analyze environmental trends and changes in biodiversity in rivers and other systems.

Links with other sections in the Patrick Center for Environmental Research have promoted multi-disciplinary environmental assessment. For example, scientists in the Fisheries Section are studying the effects of land use, riparian zone management, urbanization, dams, and point-source contaminants on biological communities. These studies incorporate studies on fish, macroinvertebrates, algae, water quality, hydrology, food web structure and geomorphology.

The Fisheries Section and Chemistry Section have conducted numerous studies of chemical contamination of fishes and other organisms. Results from these contamination assessments are used tdevelop public health advisories for fish consumption. The Fisheries Section has studied effects of entrainment and impingement on larval and adult fishes. Information from our monitoring programs are incorporated intrecommendations for aquatic system restoration.

Staff of the Fisheries Section have served as experts for a variety of agencies for verification and quality control of fish identifications. The excellent facilities of the Fisheries Section permit intensive and comprehensive scientific evaluations of aquatic systems and foster quality scientific investigation of dynamics of both lentic and lotic systems.

Capabilities

redear sunfish
  • large and small river/stream surveys
  • lake inventory and assessment
  • wetland and stream restoration (dam removal) and monitoring,
  • restoration site identification and evaluation
  • indices of biotic integrity to assess health of aquatic systems
  • preparation of fish and other aquatic specimens for contaminant analysis
  • urban park restoration and planning (including re-introduction of native fauna)
  • multiscale analyses of fish assemblage structure ranging from microhabitat watershed levels
  • taxonomic identifications for all life stages of fish, larval to adult

Facilities

The Fisheries Section develops and implements innovative sampling methods for collecting fishes of all life stages in a variety of habitats from tidal marshes tlarge rivers and bays. The Section maintains a variety of electroshocking equipment, permitting sampling in a wide range of environmental conditions. This equipment includes a dedicated, 17-ft electroshocking boat, several configurations of towbarge and walkalong electroshocking gear, and backpack electrofishing gear. The Section maintains a variety of active and passive fishing gear and small and large crafts for fish collection in all water bodies.

Our laboratory includes state-of-the-art imaging and image analysis equipment for preparation and analysis of fish otoliths (used tage fishes and texamine yearly and daily growth rates).

The fisheries lab works closely with the Ichthyology Department within the Biodiversity Group on preparation of fish and histological specimens, and curation of fishes in the permanent ichthyology collection held at the Academy. In addition, the Section has access ta world-class Natural History and Ichthyology Library with extensive taxonomic and life history literature references.

Selected Projects

American Eel Population Trends
The American eel (Anguilla rostrata) is a migratory species that spawns in the Atlantic, but spends most of its life in the streams, rivers, estuaries, and lakes of eastern North America. As they move from marine to estuarine and freshwater habitats, the eels transform from transparent glass eels to pigmented juveniles (elvers) and then to sexually immature adults called yellow eels. They spend a many as 20 years in this yellow-phase: feeding and growing until they’re ready to return to the ocean to spawn.
Ecological Effects of Small Dams
South Fork Holston River Monitoring
Neches River Monitoring
Stream Restoration Projects
Sabine River Monitoring

Educational Outreach

The Fisheries Section is active in a variety of educational programs on fisheries, local environmental issues and Patrick Center research. The Section frequently accepts student interns for summer field and lab work. Fisheries scientists conduct workshops, present research results to community groups, and frequently develop and participate in educational programs in conjunction with local watershed associations, secondary schools, and other groups. For example, members of the Fisheries Section recently participated in a Fish Identification Workshop sponsored by the Pennsylvania Chapter of the American Fisheries Society.