Biodiversity Research Institute
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Loon Program
Loon Program

BRI’s Loon Program is dedicated to assessing current and emerging threats to loons, and to collaborating with the many agencies and organizations that work to conserve loon populations across the Northern Hemisphere. Our research and conservation projects contribute to understanding basic ecology and strive to unravel the impacts of ecological stressors and how they can be lessened. 

The Program is also actively involved in assisting state and federal conservation and management agencies in monitoring efforts that include the capture, banding, sampling, and tracking of individual loons and their populations. We publish our findings through reports, management plans, and communications pieces to inform decision makers and the general public. 

Innovative Wildlife Science at Work

The Program’s innovative approach uses information from known individuals (through color-banding, geolocators, and satellite transmitters) and has population-level applications for conservation and management efforts. While studies over the past 29 years have emphasized the Common Loon, similar field efforts with the Yellow-billed Loon began in 2004. Studies involving the Red-throated Loon began in 2000 and have expanded over the past several years. Ancillary studies tracking productivity and movements of Pacific Loons are ongoing.

Loon research by BRI biologists began in 1989 with the discovery of a replicable nighttime capture method, which facilitated the ability to track individual movements and health. This capture method is responsible for the banding and recapture of more than 5,000 Common Loons. A daytime technique has since been developed that now contributes to the capture, marking, and sampling of other species of loons, including the Yellow-billed Loon, Red-throated Loon, and Pacific Loon. The ability to safely and regularly capture individual loons over time provides a way to track individual performance and health that can be related at population-level scales.

2020 International Loon/Diver Symposium


BRI is hosting the 2020 International Loon/Diver Symposium, October 19-21 in Portland, Maine.

Our goal for this symposium is to bring together researchers, conservationists, resource managers, and other experts to share knowledge and expertise for the purpose of advancing loon conservation.

Click here to learn more about the symposium and to sign up for our mailing list for updates on this event.

The overarching goal of the Loon Program is to develop applied methods that can be used to a) better understand loon ecology, and b) lessen anthropogenic threats to at-risk populations. The major categories of our scientific research and conservation efforts include:
Restore the Call Conservation Study

Restore the Call Conservation Study

In 2013, BRI initiated the largest conservation study for the Common Loon, a key bioindicator of aquatic integrity for lakes and nearshore marine ecosystems across North America. This scientific initiative provides an opportunity to identify major threats to loons while also creating solutions that strengthen current populations and restore loons to their former breeding range. Focal restoration sites are in Massachusetts, Minnesota, and Wyoming.

Click here to learn more about our Restore the Call initiative.

Contaminants Monitoring

Contaminants Monitoring

BRI began studying contaminants by documenting the exposure and effects of methylmercury in the Common Loon across North America. Research efforts have expanded to include additional contaminants (including lead, oil and emerging organic pollutants) and species (including the Red-throated and Yellow-billed Loons). Overall research goals include identifying biological mercury hotspots, conducting risk and injury assessments, and developing the use of loon species as biosentinels for monitoring contaminants in response to regulatory and other policy needs (e.g., Minamata Convention).

Contaminants monitoring projects include:

Monitoring Population Dynamics

Monitoring Population Dynamics

Monitoring uniquely color-marked or satellite-tagged loons is paramount to the continued understanding of population demographics and trends. Over time, the Program’s banding efforts have encompassed most of North America for the Common Loon (including 11 states and 8 provinces during the breeding season and 8 states during winter), three sites in the Yellow-billed Loon’s breeding range (Alaska, Nunavut, and Northwest Territories), and many sites for the Red-throated and Pacific Loons (mostly in Alaska during the breeding season). As a result of research conducted using banded and tagged loons, various state, regional, and national management and conservation efforts have been employed.

Population dynamics monitoring projects include: 

  • Rangeley Lakes Long-term Monitoring
  • Arctic Coastal Plain Loon Study
  • NRDA (North Cape, Sanborn, Bouchard Barge, Deepwater Horizon)
  • Common Loons in the Gulf of Mexico - Winter Ecology
  • Common Loons in Saskatchewan
Monitoring Movements

Monitoring Movements

Efforts to study and monitor the movements of loons across their life cycle help us learn critical information about their behavior and ecology. What is the breeding and wintering site fidelity of loons (important for managing populations)? What is the connectivity for various breeding populations with their wintering areas (important for pinpointing impacts during a marine oil spill)? What threats do breeding loon populations encounter during migration and winter (important for rare species like the Yellow-billed Loon)? The answers to such questions are more than just interesting; they are needed to make responsible conservation and management decisions that affect both wildlife and humans.

Movements monitoring projects include: 

Monitoring Specific Species

Monitoring Specific Species

The Loon Program is actively conducting studies on four of the five species of loons found worldwide: Common Loons; Yellow-billed Loons; Red-throated Loons; and Pacific Loons. Efforts are concentrated on breeding areas for each of the four species, with an emphasis on the Common Loon and on the other three species at the Program’s biostation on the tundra southeast of Barrow, Alaska (in our 9th year at that site in cooperation with the U.S. Geological Survey). Migration studies are limited to monitoring species using satellite transmitters. Winter studies are focused on Common Loons (in Louisiana and South Carolina) and Red-throated Loons (in Delaware, Maryland, North Carolina, and Virginia).

Species-specific monitoring projects include:

Adirondack Center for Loon Conservation

Adirondack Center for Loon Conservation

The Adirondack Park, a six-million-acre reserve in upstate New York, boasts hundreds of lakes and ponds—perfect breeding grounds for the Common Loon. The Adirondack Center for Loon Conservation is dedicated to improving the overall health of this environment, particularly its air and water quality, through collaborative research and education efforts. These efforts focus on the natural history of the Common Loon, while also studying conservation issues that affect all loon populations and their aquatic habitats.

Learn more about the Adirondack Center for Loon Conservation here.

Bald Eagle and Common Loon Interaction Form


As part of a collaborative effort among wildlife researchers to better understand the effect of increasing Bald Eagle populations on Common Loon populations, BRI is seeking information on observed interactions between the two species.

If you have observed an interaction between Bald Eagles and Common Loons, please share your observation with us through our Bald Eagle and Common Loon Interaction Form. Thank you!

Left: Bald Eagle and Common Loon encounter on Bow Lake, NH. © Jon Winslow

Program Director
Lucas Savoy
207-839-7600 x104

Program and Contributing Staff
Alex Dalton
Bill Hanson
Shearon Murphy
Chris Persico
Kate Taylor
Tim Welch

Adjunct Loon Research Biologists 
Lee Attix
Jeff Fair
Jim Paruk

Photo Credits: Header: © Daniel Poleschook. Portraits: Common Loon and Bald Eagle © Jon Winslow; Common Loon © Daniel Poleschook; Yellow-billed Loon © BRI-David Evers; Red-throated Loon © BRI-David Evers; Pacific Loon © BRI-Lucas Savoy. Book Jacket by RavenMark. Restore the Call © Daniel Poleschook; Contaminants Monitoring © Vincent Spagnuolo; Population Dynamics © Daniel Poleschook; Movements © Daniel Poleschook; ACLC logo by Jason Smith; Yellow-billed Loon © Ken Wright. Photocam © BRI. Loon capture © BRI-Jonathan Fiely.
Biodiversity Research Institute