Conserving the Nature of America
Press Release
Service scientists receive national recognition
U.S. Fish and Wildlife Service recognizes senior fisheries biologist and hydraulic engineer for extraordinary contributions to conservation science

March 8, 2019


Division of Public Affairs
External Affairs
Telephone: 703-358-2220

Two U.S. Fish and Wildlife Service Northeast Region employees have earned prestigious honors from the agency for their efforts to advance conservation through science.

Dr. William (Bill) Ardren, a senior fish biologist, has received the Rachel Carson Award for Exemplary Scientific Accomplishment, and Dr. Brett Towler, a hydraulic engineer, has received the Sam D. Hamilton Award for Transformational Conservation Science.

The awards were presented during a ceremony at the North American Wildlife and Natural Resources conference in Denver, Co., on March 7, 2019.

More than just contributions to a body of scientific knowledge, the awards recognize meaningful results in the face of real conservation challenges.

For Ardren, that challenge has been restoring a population of landlocked Atlantic salmon to the Lake Champlain Basin in Vermont, New York, and Quebec after more than a century’s absence. Salmon disappeared in the mid 1800s as a result of overfishing, agricultural runoff, development, and the construction of dams in rivers that prevented them from swimming upstream to spawn.

“Bill recognized that there are multiple conservation problems that make up the overarching challenge of restoring salmon in Lake Champlain, and he has brought together a broad network of conservation and academic partners to understand and help address them,” said Andrew Milliken, Project Leader for the Lake Champlain Fish and Wildlife Conservation Office.

Those problems have been both complex and confounding, including a debilitating Vitamin B deficiency caused by an invasive forage fish, low returns of hatchery raised fish to spawning grounds, and dams standing in the way of those that do attempt to migrate.

Ardren responded with a series of large-scale experiments in the hatchery, field, and lab that leveraged the capacity of staff and partners to change the population trajectory for Atlantic salmon in Lake Champlain through research, observation, and calibration – also known as adaptive management. For example, Ardren was able to identify specific chemical odorants that salmon cue in on to home to spawning grounds in the wild, and to figure out the life history stage critical for those cues. In response, he recommended changing the water source in the hatcheries from well water to brook water at a certain time of year to expose young salmon to these natural chemical cues, which has led to returns to rivers three to five times previous rates.

The results of these and other conservation solutions is highlighted by the first documented natural reproduction of salmon in over 150 years in two tributaries to Lake Champlain – the Winooski River in Vermont in 2016 and in the Boquet River in New York in 2017.

“This award acknowledges the culmination of efforts by partners working to advance the science and help address limiting factors for salmon in Lake Champlain – many of which also appear in other systems,” Arden said. He has drawn on the connections and experience developed helping to start the Conservation Genetics Lab at the Abernathy Fish Technology Center in Washington state to tap into expertise from across the global salmon community to understand better what is happening in Lake Champlain.

In Towler’s case, the motivating conservation challenge has been more than just the barriers holding fish back, but the barriers holding back fish-passage science.

“For a long time, much of the information we had on fish passage came from research on Pacific salmon on the west coast,” Towler explained. “But we have many other anadromous fish in our rivers that face unique challenges, like American shad and eel.” Although research was taking place to understand these challenges, there were fewer mechanisms for transferring this technology to practitioners in the field.

In response, Towler dedicated himself to increasing the rigor and accessibility of fish-passage engineering science through publications, education, and training. In 2010, he developed a partnership with the University of Massachusetts Amherst’s Master of Science in Civil and Environmental Engineering program to improve the ecological literacy of the next generation of fish-passage engineers through specialized courses and research opportunities. Recognizing the need for collaboration to advance fish-passage science, he wrote a memorandum of understanding to synthesize research priorities for UMass, the U.S. Geological Survey, and the Service, resulting in stronger relationships, and better conservation outcomes. In 2016, he produced the first Service manual on anadromous fish passage for the east coast, providing standardized design guidelines that are now being used by states, consultants, and other federal agencies.

“Considering the enormity of our conservation challenges, we need the best and most creative minds working towards innovative solutions,” said Will Duncan, Species and Habitat Conservation Branch Chief for the Northeast Region. “Brett embodies the creative and innovative spirit of our agency, and his scientific capabilities have produced broad-ranging benefits,” he said, explaining, “He has repeatedly shown that we can achieve great conservation outcomes while also serving the needs of private industry and citizens.”

A perfect example is a project in which Towler and Ardren worked together to address a fish-passage challenge on Vermont’s Winooski River in collaboration with Green Mountain Power. Building on Ardren’s research, Towler assessed downstream passage at a hydropower dam on the river and recommended a few small modifications to a structure that will enable salmon smolts to migrate out to Lake Champlain to mature and help their population grow.

Both Ardren and Towler embody the conviction and vision represented by the individuals their awards are named for. Rachel Carson, who was once an aquatic biologist for the Service, blazed the trail for using applied science in an adaptive management framework by scrutinizing the widespread use of chemical pesticides, resulting in a ban on DDT in the United States.

While serving as the Director of the southeast region for the U.S. Fish and Wildlife Service, Sam D. Hamilton was a champion for collaboration and innovation in leading coastal restoration efforts in the wake of hurricanes Katrina and Rita.

The Rachel Carson and Sam D. Hamilton awards are two of just three Science Awards given annually by the U.S. Fish and Wildlife Service. The third is the Science Leadership Award, which recognizes a supervisor who champions the use of science in conservation decision making, and empowers staff to accomplish scientific work and engage in the scientific community. The awards are part of the Service’s continuing dedication to strengthening the agency’s use of science in the conservation of fish, wildlife, plants, and their habitats.

Information contained in older news items may be outdated. These materials are made available as historical archival information only. Individual contacts have been replaced with general External Affairs office information. No other updates have been made to the information and we do not guarantee current accuracy or completeness.

The mission of the U.S. Fish and Wildlife Service is working with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. We are both a leader and trusted partner in fish and wildlife conservation, known for our scientific excellence, stewardship of lands and natural resources, dedicated professionals, and commitment to public service. For more information on our work and the people who make it happen, visit

For more information on our work and the people who make it happen, visit Connect with our Facebook page, follow our tweets, watch our YouTube Channel and download photos from our Flickr page.