The Common Loon is listed by Wyoming Game & Fish as a Tier 1 Species of Greatest Conservation Need and is considered the rarest breeding bird in Wyoming. The population of only 21 territorial pairs can be found on lakes in the northwest portion of the state in Yellowstone National Park, Grand Teton National Park, and the Bridger-Teton and Caribou-Targhee National Forests. These loons are at the southern extent of the species' range and are isolated by over 200 miles from the nearest breeding population.
Wyoming’s landscape is a study in contrasts, from shortgrass prairies and sagebrush steppes to the stunning peaks of the Rocky Mountains.
Yellowstone National Park is dedicated to preserving the state’s natural environments and native species. One such species, the Common Loon, is in danger of disappearing. Since the mid-2000s, this population has declined by nearly 42 percent and is considered one of the most southern populations in its range.
The Common Loon is considered the highest ranked Species of Greatest Need by the Wyoming Game and Fish Department.
In Wyoming, the Common Loon is the rarest breeding bird; they are listed as a Species of Greatest Conservation Need, as determined by the Wyoming Game and Fish Department. In 2012, Biodiversity Research Institute (BRI), in partnership with Yellowstone National Park (YNP), initiated a study to monitor and understand the local breeding loon population. In 2013, BRI created a dedicated working group in collaboration with governmental agencies including Yellowstone and Grand Teton National Parks, the Wyoming Game and Fish Department, and Bridger-Teton and Caribou-Targhee National Forests. The goals of BRI within the Wyoming Loon Working Group are to ensure that Wyoming’s small and isolated breeding population of Common Loons is self-sustaining. A wider understanding of loon ecology and threats will be important to assist governmental agencies with management and outreach efforts.
With only 22 observed territorial pairs, the Wyoming loon population is one of the smallest and most isolated in the species range (Figure 1). This population is not only the most southern loon population in the west, but it is also isolated from contiguous populations to the north by more than 220 miles. This makes immigration, and therefore dispersal and rescue from other populations, unlikely. The breeding population is distributed across:
Surveys from 2015-2019 identified several lakes with oversummering individuals and occasionally territorial pairs in the Wind River Range.
Despite the small size of the population, the number of territorial pairs in Wyoming has been trending upward since BRI began conducting standardized surveys in 2013 (when only 14 pairs were observed).
Loon productivity is best measured as chicks surviving (i.e., those living at least 6 weeks) per territorial pair. In Wyoming, 20 of the 30 years of measured productivity since 1989 were above the well-established sustainability threshold of 0.48 CS/TP value. This statistic is encouraging. For the past nine years, productivity has been above 0.48 CS/TP, which may be related to the increase in territorial pairs now being observed. Having exceptionally low productivity years, such as in 1993, 2004, 2008, and 2011, are typical of loon populations over time. Conversely, exceptional years were recorded in 1989, 2014, and in 2019.
Evidence of the loon’s ability to acclimate to changing conditions demonstrates that properly designed conservation efforts can often be beneficial. General threats to North America’s loon population are well-established (Figure 6). In Wyoming, BRI’s research over the past seven years recommends prioritizing the following actions to help understand and protect loon breeding populations and maintain their long-term sustainability.
BRI, in collaboration with Ricketts Conservation Foundation, Wyoming Game & Fish Department (WGFD), Yellowstone National Park, recently published a two page summary brochure titled "Common Loon Research and Monitoring in Wyoming."
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