A silver-phase American Eel in a northeastern river begins migrating downstream to the ocean to spawn in the Sargasso Sea. The migration can span hundreds of kilometers in freshwater rivers and thousands of kilometers at sea.
Alexander Haro, Ph.D.
Dr. Haro is a Fish Biologist at the USGS S.O. Conte Anadromous Fish Research Laboratory at Turners Falls, Massachusetts, and serves as Section Leader of the Fish Passage Engineering Section.
His present work involves migratory fish behavior, design, engineering, and evaluation of fish passage structures, fish swimming performance, and ecology and management of American eels. He is also an Adjunct Associate Professor at the University of Massachusetts Department of Environmental Conservation and serves as a major advisor for graduate students, as well as an instructor for courses in fisheries biology.
Science and Products
Passage Technologies for American Eels
The American eel ( Anguilla rostrata ) migrates into freshwater in the juvenile (glass eel and elver) stage, feeds and grows in freshwater habitats, and migrates downstream to the ocean to spawn as an adult. Migrating eels frequently encounter barriers in river environments, primarily in the form of dams, that limit access of juveniles to upstream growth habitat, and can injure or kill adult...
Evaluation and Development of Fish Passage Structures and Technologies
Dams can be found in just about every major river, and for good reason. Society has received many benefits like flood control, hydropower, water supply storage, and places to recreate. However, many fish and other life in our rivers can’t swim around these barriers. Often, the best spot for a fish to live and reproduce is out of reach because they can’t pass by a dam. This has not gone unnoticed...
Fish Passage
A major focus of USGS-LSC is the design and evaluation of state-of the-art upstream and downstream fish passage structures for hydropower facilities of different sizes and locations and for different fish species, including endangered sturgeons and Atlantic salmon. Performance, physiology, behavior and energetics of each fish species are tested in-house for each design.
Adult silver phase American Eel
A silver-phase American Eel in a northeastern river begins migrating downstream to the ocean to spawn in the Sargasso Sea. The migration can span hundreds of kilometers in freshwater rivers and thousands of kilometers at sea.
Eel climbing substrate
Left: Prototype ABS plastic eel climbing ramp under development and testing at CAFRL. New substrate design allows for passage of a wider size range of eels with less need for precise flow regulation. Right: juvenile eel climbing wetted ABS plastic substrate.
Left: Prototype ABS plastic eel climbing ramp under development and testing at CAFRL. New substrate design allows for passage of a wider size range of eels with less need for precise flow regulation. Right: juvenile eel climbing wetted ABS plastic substrate.
Release of radio-tagged silver phase American Eel
Radio-tagged silver phase American Eels being released for a CAFRL telemetry study of downstream passage of eels at hydroelectric dams on the Shetucket River, Connecticut.
Radio-tagged silver phase American Eels being released for a CAFRL telemetry study of downstream passage of eels at hydroelectric dams on the Shetucket River, Connecticut.
Eel airlift bypass prototype
Prototype design of an airlift developed at CAFL to transport downstream migrant eels through a bypass pipe and away from turbine intakes. The airlift design passes eels as well as a conventional siphon or gravity pipe.
Prototype design of an airlift developed at CAFL to transport downstream migrant eels through a bypass pipe and away from turbine intakes. The airlift design passes eels as well as a conventional siphon or gravity pipe.
Eel electrosensitivity test apparatus
Apparatus used to test the sensitivity of eels to low-voltage pulsed DC electric fields. Knowledge of sensitivity of eels to electric fields enables development of behavioral barriers that use electricity to guide eels away from turbine intakes.
Apparatus used to test the sensitivity of eels to low-voltage pulsed DC electric fields. Knowledge of sensitivity of eels to electric fields enables development of behavioral barriers that use electricity to guide eels away from turbine intakes.
Science and Products
- Science
Passage Technologies for American Eels
The American eel ( Anguilla rostrata ) migrates into freshwater in the juvenile (glass eel and elver) stage, feeds and grows in freshwater habitats, and migrates downstream to the ocean to spawn as an adult. Migrating eels frequently encounter barriers in river environments, primarily in the form of dams, that limit access of juveniles to upstream growth habitat, and can injure or kill adult...Evaluation and Development of Fish Passage Structures and Technologies
Dams can be found in just about every major river, and for good reason. Society has received many benefits like flood control, hydropower, water supply storage, and places to recreate. However, many fish and other life in our rivers can’t swim around these barriers. Often, the best spot for a fish to live and reproduce is out of reach because they can’t pass by a dam. This has not gone unnoticed...Fish Passage
A major focus of USGS-LSC is the design and evaluation of state-of the-art upstream and downstream fish passage structures for hydropower facilities of different sizes and locations and for different fish species, including endangered sturgeons and Atlantic salmon. Performance, physiology, behavior and energetics of each fish species are tested in-house for each design. - Data
- Multimedia
Adult silver phase American Eel
A silver-phase American Eel in a northeastern river begins migrating downstream to the ocean to spawn in the Sargasso Sea. The migration can span hundreds of kilometers in freshwater rivers and thousands of kilometers at sea.
A silver-phase American Eel in a northeastern river begins migrating downstream to the ocean to spawn in the Sargasso Sea. The migration can span hundreds of kilometers in freshwater rivers and thousands of kilometers at sea.
Eel climbing substrateLeft: Prototype ABS plastic eel climbing ramp under development and testing at CAFRL. New substrate design allows for passage of a wider size range of eels with less need for precise flow regulation. Right: juvenile eel climbing wetted ABS plastic substrate.
Left: Prototype ABS plastic eel climbing ramp under development and testing at CAFRL. New substrate design allows for passage of a wider size range of eels with less need for precise flow regulation. Right: juvenile eel climbing wetted ABS plastic substrate.
Release of radio-tagged silver phase American EelRadio-tagged silver phase American Eels being released for a CAFRL telemetry study of downstream passage of eels at hydroelectric dams on the Shetucket River, Connecticut.
Radio-tagged silver phase American Eels being released for a CAFRL telemetry study of downstream passage of eels at hydroelectric dams on the Shetucket River, Connecticut.
Eel airlift bypass prototypePrototype design of an airlift developed at CAFL to transport downstream migrant eels through a bypass pipe and away from turbine intakes. The airlift design passes eels as well as a conventional siphon or gravity pipe.
Prototype design of an airlift developed at CAFL to transport downstream migrant eels through a bypass pipe and away from turbine intakes. The airlift design passes eels as well as a conventional siphon or gravity pipe.
Eel electrosensitivity test apparatusApparatus used to test the sensitivity of eels to low-voltage pulsed DC electric fields. Knowledge of sensitivity of eels to electric fields enables development of behavioral barriers that use electricity to guide eels away from turbine intakes.
Apparatus used to test the sensitivity of eels to low-voltage pulsed DC electric fields. Knowledge of sensitivity of eels to electric fields enables development of behavioral barriers that use electricity to guide eels away from turbine intakes.
- Publications
- News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government