EESC's Fish biologist, Aaron Heisey, holds a shortnose sturgeon (acipenser brevirostrum) caught and released on the Merrimack River outside Lowell, Massachusetts. This freshwater fish was captured as part of a 2024 population dynamics study.
Brett Towler, Ph.D., P.E.
Dr. Brett Towler is a Science Team Manager with the Eastern Ecological Science Center at the S.O. Conte Research Laboratory in Turners Falls, MA.
Dr. Towler is a hydraulic engineer and a fish passage expert with 25+ combined years of experience as a consultant, educator, researcher and practicing civil engineer. His experience is primarily in the fields of hydraulic engineering, surface water hydrology, river mechanics, dam safety, hydropower, and fish passage and protection.
He serves as the Fish Passage Design & Analysis Team Manager and Senior Manager at EESC's Conte Lab located on the Connecticut River in Western Massachusetts. In these roles, he is responsible for the project management of multiple interdisciplinary studies, the development of partnerships, integrating research with other USGS programs, and the coordination of laboratory activities among scientists reporting to multiple EESC science and science-enabling teams.
Science and Products
Fish Passage Design and Analysis at the S.O. Conte Research Laboratory
There are more than 92,000 dams in the United States, of which at least 3% of these produce hydropower. Hydropower projects create renewable energy but also can alter habitats, restrict upstream and downstream movements of fishes and other aquatic organisms, and may stress, injure or kill migrant fishes and other aquatic organisms. In addition, there are more than 5 million culverts and other road...
Scientist nets shortnose sturgeon on the Merrimack
EESC's Fish biologist, Aaron Heisey, holds a shortnose sturgeon (acipenser brevirostrum) caught and released on the Merrimack River outside Lowell, Massachusetts. This freshwater fish was captured as part of a 2024 population dynamics study.
Kyle Hubbard, assists with PIT antennas for East Coast Ladder study
Biological Science Technician, Kyle Hubbard, assists with checking and installing passive integrated transponder antennas for Kevin Mulligan's East Coast Ladder study in the East flume of the Fish Passage Complex at the Conte Lab.
Biological Science Technician, Kyle Hubbard, assists with checking and installing passive integrated transponder antennas for Kevin Mulligan's East Coast Ladder study in the East flume of the Fish Passage Complex at the Conte Lab.
Comparison of the novel D-Cylinder and standard Denil fish ladders
Two 4-foot wide baffled chute fishways are tested side-by-side in the Conte Lab's Fish Passage Complex's east flume. The fish ladders are instrumented with passive integrated transponder antennas/reader. River herring, collected from the mouth of the Chicopee River are tested to assess entry and ascent rates.
Two 4-foot wide baffled chute fishways are tested side-by-side in the Conte Lab's Fish Passage Complex's east flume. The fish ladders are instrumented with passive integrated transponder antennas/reader. River herring, collected from the mouth of the Chicopee River are tested to assess entry and ascent rates.
Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers
linkUSGS Fish Biologist Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers.
Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers
linkUSGS Fish Biologist Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers.
Constructing a Denil fishway baffle
EESC facilities and Fish Passage Design & Analysis team members constructed wooden Denil fishway baffles for the 2023 D-Cylinder study in Conte's Fish Passage Complex
EESC facilities and Fish Passage Design & Analysis team members constructed wooden Denil fishway baffles for the 2023 D-Cylinder study in Conte's Fish Passage Complex
Steel support structure installed for fish ladder experiment
A steel support structure for the upcoming 2023 D-Cylinder fish ladder study installed in the East Flume of the Conte Research Lab's Fish Passage Complex by USGS employees Rolando (Marty) Garcia and Aaron Heisey.
A steel support structure for the upcoming 2023 D-Cylinder fish ladder study installed in the East Flume of the Conte Research Lab's Fish Passage Complex by USGS employees Rolando (Marty) Garcia and Aaron Heisey.
Aerial photo of the USGS Conte Research Laboratory
Aerial photo of the USGS Conte Research Laboratory located on the Connecticut River in Turners Falls, Massachusetts. Photo take in mid September of 2022.
Aerial photo of the USGS Conte Research Laboratory located on the Connecticut River in Turners Falls, Massachusetts. Photo take in mid September of 2022.
Planting the pollinator garden at the Conte Lab
Sam Droege (fore) arrived from Patuxent with plants for the Conte Lab's new pollinator garden. Sam Parker (back) assists with the planting.
Sam Droege (fore) arrived from Patuxent with plants for the Conte Lab's new pollinator garden. Sam Parker (back) assists with the planting.
Collecting shad for study at Holyoke fish lift
Steve Walk and crew collect 80+ American shad from the trap at the Holyoke fish lift on the Connecticut River. Shad behavior will be studied in Kevin Mulligan's V-Trap study.
Steve Walk and crew collect 80+ American shad from the trap at the Holyoke fish lift on the Connecticut River. Shad behavior will be studied in Kevin Mulligan's V-Trap study.
Palisade study trials in the Fish Passage Complex with American shad
The Palisade Entrance, a novel fishway entrance, was constructed and tested at the Conte Lab's Fish Passage Complex. Trials were conducted with multiple species, including American shad, to determine entry rate under a variety of hydraulic conditions.
The Palisade Entrance, a novel fishway entrance, was constructed and tested at the Conte Lab's Fish Passage Complex. Trials were conducted with multiple species, including American shad, to determine entry rate under a variety of hydraulic conditions.
Seining fish into the Burroughs Pond following the first shad trial
Kevin Molongoski (left) and Steve Walk (right) seine adult American shad back into the Burroughs Ponds (resting/exercising pools) following the completion of trial through the Palisade Entrance.
Kevin Molongoski (left) and Steve Walk (right) seine adult American shad back into the Burroughs Ponds (resting/exercising pools) following the completion of trial through the Palisade Entrance.
The first shad trial in the Palisade Entrance is complete
Kevin Mulligan coordinates the end of the first shad trail in the Palisade Entrance study, a DOE funded study investigating the efficiency of a novel fishway entrance.
Kevin Mulligan coordinates the end of the first shad trail in the Palisade Entrance study, a DOE funded study investigating the efficiency of a novel fishway entrance.
Tagging and measuring American shad for the Palisade fishway study
Kevin Molongoski (fore) carries a tagged adult American shad from the fish truck to the Burroughs Pond in the Conte Lab's Fish Passage Complex. Kevin Mulligan (back) prepares another passive integrated transponder (PIT) tag.
Kevin Molongoski (fore) carries a tagged adult American shad from the fish truck to the Burroughs Pond in the Conte Lab's Fish Passage Complex. Kevin Mulligan (back) prepares another passive integrated transponder (PIT) tag.
Adjustments to the O2 delivery system on Conte's fish truck
Steve Walk makes final adjustments to innovative oxygen delivery system recently installed on FPDA team's fish truck.
Steve Walk makes final adjustments to innovative oxygen delivery system recently installed on FPDA team's fish truck.
Solar Panel Installation
This is the set up of the solar panels at Blackwater National Wildlife Preserve that will be used to power the newly installed sap flow sensors on site. These solar panels will decrease the number of required trips to the site to change batteries and will contribute to the undisturbed data flow from the sensors.
This is the set up of the solar panels at Blackwater National Wildlife Preserve that will be used to power the newly installed sap flow sensors on site. These solar panels will decrease the number of required trips to the site to change batteries and will contribute to the undisturbed data flow from the sensors.
Final preparations for the 2022 Delaware River American shad study
Micah Kieffer, John Burns (volunteer), and Ted Castro-Santos performing final preparations on the 23 foot Commander for service in the initial year of EESC's Delaware River shad study.
Micah Kieffer, John Burns (volunteer), and Ted Castro-Santos performing final preparations on the 23 foot Commander for service in the initial year of EESC's Delaware River shad study.
Atlantic sturgeon recovered for necropsy
Micah Kieffer, EESC sturgeon biologist and a member of NOAA's sturgeon recovery network, returns to the S.O. Conte Research Laboratory with a young adult Atlantic sturgeon that was found on the shore in Reverse, Massachusetts in February of 2022. Fish is scheduled for necropsy in the days to come.
Micah Kieffer, EESC sturgeon biologist and a member of NOAA's sturgeon recovery network, returns to the S.O. Conte Research Laboratory with a young adult Atlantic sturgeon that was found on the shore in Reverse, Massachusetts in February of 2022. Fish is scheduled for necropsy in the days to come.
Alex Haro clearing flume during lamprey light study
During Nov-Dec 2021 study in the Conte Fish Passage Complex (flume bldg), juvenile lamprey transformers were tagged and released in the 10' wide west flume to evaluate their response to various conditions including water velocity and light. Alex Haro is shown here clearing the flume of fish that were not captured in the trap or moved downstream.
During Nov-Dec 2021 study in the Conte Fish Passage Complex (flume bldg), juvenile lamprey transformers were tagged and released in the 10' wide west flume to evaluate their response to various conditions including water velocity and light. Alex Haro is shown here clearing the flume of fish that were not captured in the trap or moved downstream.
Juvenile lamprey collection in the power canal
The de-watered Turners Falls power canal taken from the S.O. Conte Lab intakes. Juvenile lamprey were collected in the drained water canal via fyke-type traps seen in the lower left.
The de-watered Turners Falls power canal taken from the S.O. Conte Lab intakes. Juvenile lamprey were collected in the drained water canal via fyke-type traps seen in the lower left.
Science and Products
Fish Passage Design and Analysis at the S.O. Conte Research Laboratory
There are more than 92,000 dams in the United States, of which at least 3% of these produce hydropower. Hydropower projects create renewable energy but also can alter habitats, restrict upstream and downstream movements of fishes and other aquatic organisms, and may stress, injure or kill migrant fishes and other aquatic organisms. In addition, there are more than 5 million culverts and other road...
Scientist nets shortnose sturgeon on the Merrimack
EESC's Fish biologist, Aaron Heisey, holds a shortnose sturgeon (acipenser brevirostrum) caught and released on the Merrimack River outside Lowell, Massachusetts. This freshwater fish was captured as part of a 2024 population dynamics study.
EESC's Fish biologist, Aaron Heisey, holds a shortnose sturgeon (acipenser brevirostrum) caught and released on the Merrimack River outside Lowell, Massachusetts. This freshwater fish was captured as part of a 2024 population dynamics study.
Kyle Hubbard, assists with PIT antennas for East Coast Ladder study
Biological Science Technician, Kyle Hubbard, assists with checking and installing passive integrated transponder antennas for Kevin Mulligan's East Coast Ladder study in the East flume of the Fish Passage Complex at the Conte Lab.
Biological Science Technician, Kyle Hubbard, assists with checking and installing passive integrated transponder antennas for Kevin Mulligan's East Coast Ladder study in the East flume of the Fish Passage Complex at the Conte Lab.
Comparison of the novel D-Cylinder and standard Denil fish ladders
Two 4-foot wide baffled chute fishways are tested side-by-side in the Conte Lab's Fish Passage Complex's east flume. The fish ladders are instrumented with passive integrated transponder antennas/reader. River herring, collected from the mouth of the Chicopee River are tested to assess entry and ascent rates.
Two 4-foot wide baffled chute fishways are tested side-by-side in the Conte Lab's Fish Passage Complex's east flume. The fish ladders are instrumented with passive integrated transponder antennas/reader. River herring, collected from the mouth of the Chicopee River are tested to assess entry and ascent rates.
Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers
linkUSGS Fish Biologist Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers.
Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers
linkUSGS Fish Biologist Aaron Heisey and EESC colleagues enter the east flume in the Conte Lab's Fish Passage Complex after the conclusion of a study trial to recover adult white suckers.
Constructing a Denil fishway baffle
EESC facilities and Fish Passage Design & Analysis team members constructed wooden Denil fishway baffles for the 2023 D-Cylinder study in Conte's Fish Passage Complex
EESC facilities and Fish Passage Design & Analysis team members constructed wooden Denil fishway baffles for the 2023 D-Cylinder study in Conte's Fish Passage Complex
Steel support structure installed for fish ladder experiment
A steel support structure for the upcoming 2023 D-Cylinder fish ladder study installed in the East Flume of the Conte Research Lab's Fish Passage Complex by USGS employees Rolando (Marty) Garcia and Aaron Heisey.
A steel support structure for the upcoming 2023 D-Cylinder fish ladder study installed in the East Flume of the Conte Research Lab's Fish Passage Complex by USGS employees Rolando (Marty) Garcia and Aaron Heisey.
Aerial photo of the USGS Conte Research Laboratory
Aerial photo of the USGS Conte Research Laboratory located on the Connecticut River in Turners Falls, Massachusetts. Photo take in mid September of 2022.
Aerial photo of the USGS Conte Research Laboratory located on the Connecticut River in Turners Falls, Massachusetts. Photo take in mid September of 2022.
Planting the pollinator garden at the Conte Lab
Sam Droege (fore) arrived from Patuxent with plants for the Conte Lab's new pollinator garden. Sam Parker (back) assists with the planting.
Sam Droege (fore) arrived from Patuxent with plants for the Conte Lab's new pollinator garden. Sam Parker (back) assists with the planting.
Collecting shad for study at Holyoke fish lift
Steve Walk and crew collect 80+ American shad from the trap at the Holyoke fish lift on the Connecticut River. Shad behavior will be studied in Kevin Mulligan's V-Trap study.
Steve Walk and crew collect 80+ American shad from the trap at the Holyoke fish lift on the Connecticut River. Shad behavior will be studied in Kevin Mulligan's V-Trap study.
Palisade study trials in the Fish Passage Complex with American shad
The Palisade Entrance, a novel fishway entrance, was constructed and tested at the Conte Lab's Fish Passage Complex. Trials were conducted with multiple species, including American shad, to determine entry rate under a variety of hydraulic conditions.
The Palisade Entrance, a novel fishway entrance, was constructed and tested at the Conte Lab's Fish Passage Complex. Trials were conducted with multiple species, including American shad, to determine entry rate under a variety of hydraulic conditions.
Seining fish into the Burroughs Pond following the first shad trial
Kevin Molongoski (left) and Steve Walk (right) seine adult American shad back into the Burroughs Ponds (resting/exercising pools) following the completion of trial through the Palisade Entrance.
Kevin Molongoski (left) and Steve Walk (right) seine adult American shad back into the Burroughs Ponds (resting/exercising pools) following the completion of trial through the Palisade Entrance.
The first shad trial in the Palisade Entrance is complete
Kevin Mulligan coordinates the end of the first shad trail in the Palisade Entrance study, a DOE funded study investigating the efficiency of a novel fishway entrance.
Kevin Mulligan coordinates the end of the first shad trail in the Palisade Entrance study, a DOE funded study investigating the efficiency of a novel fishway entrance.
Tagging and measuring American shad for the Palisade fishway study
Kevin Molongoski (fore) carries a tagged adult American shad from the fish truck to the Burroughs Pond in the Conte Lab's Fish Passage Complex. Kevin Mulligan (back) prepares another passive integrated transponder (PIT) tag.
Kevin Molongoski (fore) carries a tagged adult American shad from the fish truck to the Burroughs Pond in the Conte Lab's Fish Passage Complex. Kevin Mulligan (back) prepares another passive integrated transponder (PIT) tag.
Adjustments to the O2 delivery system on Conte's fish truck
Steve Walk makes final adjustments to innovative oxygen delivery system recently installed on FPDA team's fish truck.
Steve Walk makes final adjustments to innovative oxygen delivery system recently installed on FPDA team's fish truck.
Solar Panel Installation
This is the set up of the solar panels at Blackwater National Wildlife Preserve that will be used to power the newly installed sap flow sensors on site. These solar panels will decrease the number of required trips to the site to change batteries and will contribute to the undisturbed data flow from the sensors.
This is the set up of the solar panels at Blackwater National Wildlife Preserve that will be used to power the newly installed sap flow sensors on site. These solar panels will decrease the number of required trips to the site to change batteries and will contribute to the undisturbed data flow from the sensors.
Final preparations for the 2022 Delaware River American shad study
Micah Kieffer, John Burns (volunteer), and Ted Castro-Santos performing final preparations on the 23 foot Commander for service in the initial year of EESC's Delaware River shad study.
Micah Kieffer, John Burns (volunteer), and Ted Castro-Santos performing final preparations on the 23 foot Commander for service in the initial year of EESC's Delaware River shad study.
Atlantic sturgeon recovered for necropsy
Micah Kieffer, EESC sturgeon biologist and a member of NOAA's sturgeon recovery network, returns to the S.O. Conte Research Laboratory with a young adult Atlantic sturgeon that was found on the shore in Reverse, Massachusetts in February of 2022. Fish is scheduled for necropsy in the days to come.
Micah Kieffer, EESC sturgeon biologist and a member of NOAA's sturgeon recovery network, returns to the S.O. Conte Research Laboratory with a young adult Atlantic sturgeon that was found on the shore in Reverse, Massachusetts in February of 2022. Fish is scheduled for necropsy in the days to come.
Alex Haro clearing flume during lamprey light study
During Nov-Dec 2021 study in the Conte Fish Passage Complex (flume bldg), juvenile lamprey transformers were tagged and released in the 10' wide west flume to evaluate their response to various conditions including water velocity and light. Alex Haro is shown here clearing the flume of fish that were not captured in the trap or moved downstream.
During Nov-Dec 2021 study in the Conte Fish Passage Complex (flume bldg), juvenile lamprey transformers were tagged and released in the 10' wide west flume to evaluate their response to various conditions including water velocity and light. Alex Haro is shown here clearing the flume of fish that were not captured in the trap or moved downstream.
Juvenile lamprey collection in the power canal
The de-watered Turners Falls power canal taken from the S.O. Conte Lab intakes. Juvenile lamprey were collected in the drained water canal via fyke-type traps seen in the lower left.
The de-watered Turners Falls power canal taken from the S.O. Conte Lab intakes. Juvenile lamprey were collected in the drained water canal via fyke-type traps seen in the lower left.
*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