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Loon Program - Washington
Loon Program - Washington

Loon Research in Washington

Partnered with the Washington Department of Fish and Game (King County), United States Forest Service (Colville District), Spokane Audubon, and Hancock Timber Resource Group, BRI is investigating Common Loon population trends throughout the state. Since beginning annual banding efforts in 1995, BRI has banded more than 100 Common Loons in Washington State.

Lead Investigator: Lucas Savoy
Contributing BRI Staff: Chris Persico


NEW: Common Loon Status Report


BRI's new publication, Common Loon Status Report 2020: Washington, summarizes the recent trends in the breeding population of Common Loons in Washington State and the Western U.S. The report highlights trends in population, reproduction status, conservation concerns, and recommendations for future monitoring and management.

Download the PDF here.

Project Overview

Project Overview

Our banding efforts allowed researchers to verify that many of the adult loons were dying due to fishing-related activities, such as ingestion of lead tackle, and entanglement in monofilament. Because of these findings, the Washington Department of Fish and Game excluded the use of lead tackle on 10 of the 11 breeding lakes Common Loons use in the state.
Overall Study Goals

Overall Study Goals

  • Assist and lead in the capture and color-banding of Common Loons in both the western and eastern parts of the state
  • Collect tissue samples of Common Loons and analyze them for lead and mercury, two environmental toxins that adversely impact loon breeding success
  • Obtain geolocators previously deployed in earlier years to identify migration patterns and winter use areas

Current Status

Washington Common Loon population study area. Loons from Bonaparte, Swan, and South Twin Lakes represent individuals who have held territories for the longest terms. (Age of each loon assumes age at first breeding is six years.)

The statewide breeding loon population is currently 22 known pairs, with an estimated six pairs in the western range and 14 pairs in northeastern Washington.

In Washington the number of known territorial pairs has ranged from 6 to 23 from 1996-2019. This variation over the 24-year time period is typical for bird species.

Productivity in Washington for the last 24 years was above the well-established sustainability threshold value of 0.48 chicks surviving per territorial pair. For the past seven years in particular, productivity has remained above threshold levels, and this may be related to the increase in territorial pairs now being observed.

Conservation Concerns

Conservation Concerns

Protection of loon breeding habitat is critical to maintaining the integrity of loon populations and avoiding increased degradation of suitable breeding habitat. Because of its status at the top of the food web, high visibility to people, limited dispersal ability, and relatively slow replacement rate, the loon is widely used as an indicator species for tracking aquatic integrity.

General threats to this population during the breeding season include: (1) direct human disturbance to nests and chicks; (2) water level fluctuations of territorial lakes and reservoirs; (3) changes in prey abundance; and, (4) contaminants. Washington’s wintering loon population is susceptible in marine waters (see Figure 1) to hazards such as oil spills and commercial fishing nets. Loons are long-lived and have relatively low fecundity—therefore, Washington’s breeding population is at particularly high risk to anthropogenic stressors. 

Recommendations for 2020

Evidence of the loon’s ability to acclimate to changing conditions demonstrates that properly designed conservation efforts can be beneficial. General threats to North America’s loon population are well-established. We recommend prioritizing the following actions to help maintain their long-term sustainability.


  • Continue standardized surveys of breeding loon population.
  • Continue to band and track adults and returning  juveniles to determine mate and site fidelity, local territory movements, age at first breeding, longevity, and individual performance.
  • Enlist the help of additional citizen scientists at breeding territories to function as Loon Rangers.
  • Collect more information on reproductive success and specific movements during and after the breeding season to assess long-term sustainability of loon populations west of the Cascade Mountains.
  • Continue tracking mortality to document trends and the effectiveness of current lead ban regulations.
  • Continue monitoring number and locations of bald eagle predation.


  • Continue capturing, banding, and sampling loons to track individuals and determine health, including contaminant body burdens (e.g., mercury and lead and stable isotopes).
  • Determine inter- and intraseasonal movements with geolocators and satellite transmitters.


  • Expand the use of artificial nest platforms. Use avian guards around nest sites and on artificial nest platforms.
  • Assess the impact of Washington’s Bald Eagle population on loons.
  • Increase the ban on lead fishing tackle statewide. 


  • Continue to increase awareness of the presence and requirements of breeding loons using dioramas, exhibits, brochures, and video presentations.
  • Post educational signs at boat launches, trail heads, kiosks, and visitor centers.


  • Collaborators Washington Department of Fish & Game
  • U.S. Forest Service (Colville District)
  • Hancock Timber Resource Group
  • Seattle Public Utilities
  • Tacoma Water District
  • Colville Confederated Tribes
  • Spokane Audubon
Photo Credits: All Common Loon Photos © Daniel Poleschook
Biodiversity Research Institute