Montana has the largest population of Common Loons in the western United States with 72 territorial pairs. While the number of territorial pairs has fluctuated since 2006, the overall number of pairs has increased. In order to support the expanding work conducted by Montana Fish, Wildlife, and Parks and the Montana Common Loon Working Group, BRI staff will broaden current monitoring efforts to improve our understanding of Montana loon population dynamics to ensure the continued growth of the population.
Lead Investigator: Allison Byrd
Assist MFWP with surveys of loon territories and with identifying research in support of the Montana Comprehensive Fish and Wildlife Conservation Strategy Plan, including:
Lakes will be observed using binoculars or a spotting scope to determine the presence or absence of loons. Kayaks or boats will be used to survey lakes when appropriate. If use of watercraft is not possible, lake perimeters where breeding is occurring or suspected will be searched on foot for the presence of nests.
Capture and Banding
Loons will be captured using both nocturnal and diurnal techniques developed by BRI. Captured loons will be banded for individual identification using unique combinations of color-marked bands and numbered U.S. Geological Survey aluminum bands.
Blood and Feather Collection
We will follow established tissue sample collection protocols. We will non-lethally collect loon blood samples to evaluate short-term mercury accumulation in the loons. Feather samples will be collected from the adults (and from juvenile loons with fully emerged feathers) to provide an indication of long-term mercury accumulation.
Loon eggs will be collected when a nest is confirmed abandoned or has been over-incubated (due to inviable egg/s). The average length of incubation for Common Loons is 28 days; therefore eggs will not be deemed inviable until they have been incubated many days or weeks beyond this length of time.
Biologists may encounter deceased loon adults or chicks. If this occurs, the carcass will be collected in a sealable plastic bag and marked with the location of the carcass, the date, and any other pertinent information. When possible, a GPS location of the carcass will be taken. If the carcass is reasonably fresh, it will be refrigerated. Michelle Kneeland, DVM will be contacted to determine if she is available for a necropsy. If Dr. Kneeland is not available, or if the carcass is decaying, it will be stored in a freezer until a necropsy can be performed.
1. Conduct surveys via shoreline, kayak, boat, and plane
2. Assist MFWP with banding efforts
3. Coordinate loon egg and carcass collection
4. Set-up, monitor, and remove nest cameras when appropriate; disseminate photos, video, and information
5. Assist MFWP biologist with:
6. Monitor lakes in Glacier National Park where gill-netting activities are occurring
7. Assist the Wyoming and British Columbia loon projects when necessary for capture or surveys
8. Implement/Initiate further research projects when relevant
Montana’s topography is defined by the Continental Divide, which creates distinct eastern and western regions that encompass snow-covered mountains, prairie lands, and alpine forests. Glacier National Park is dedicated to preserving the state’s natural environments and native species. One such species, the Common Loon, is increasing after years of dedicated conservation and management. Although the number of territorial pairs has increased by 23 percent since 2000, continued health requires diligent monitoring.
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