Phalarope Research from Mono Lake to Laguna Mar Chiquita
By: Ryan Carle, Oikonos
If you are lucky, you have stood on the shores of a saline lake as thousands of tiny swimming shorebirds known as phalaropes take to the air, swirling and making lightning quick hairpin turns in unison. Maybe you’ve heard the “whoosh” of their wings as hundreds fly low over your kayak. If so, you’ll know these diminutive charmers embody the unique spirit of saline lakes and can capture your heart.
If you have not yet met these little shorebirds, –they are fragile and strong, elegant and silly, ocean-going and desert-going, and altogether inspiring. Phalaropes breed in northern latitudes, stop at saline lakes in the western U.S. to rest and refuel for their migration, and ultimately continue to saline lakes in the Andes (Wilson’s Phalarope Phalaropus tricolor), and the Pacific Ocean off South America (Red-necked Phalarope Phalaropus lobatus). At their saline lake “staging” sites in the Unites States, such as Mono Lake, California, or Great Salt Lake, Utah Wilson’s phalaropes gorge on brine flies and double their body weight, from the mass of one AA battery, to the mass of two AA batteries before they take-off on a non-stop, flight of more than 5,000 miles to South America.
Left: Wilson’s phalaropes flocking at Mono Lake. Photo: Samuel Rapp. Right: Oikonos ecologist Kyriana Tarr surveys for phalaropes at Mono Lake with WHSRN staff Marcela Castellino, who was visiting from Argentina. Photo: Ryan Carle.
When given the chance, phalaropes have won many hearts, but still have received relatively little conservation attention. Shorebirds are showing dramatic declines worldwide, and other species with urgent conservation needs have been prioritized. However, the data we do have suggests that phalaropes are also declining. Since phalaropes concentrate at saline lakes during migration, data from lakes like Mono Lake can help us better understand the status of phalaropes. From 2019-2022, Oikonos and partners have surveyed phalaropes bi-weekly through the boreal summer at Mono Lake, in the first surveys with such consistency in decades. Surveys were conducted by counting birds from a series of boat and shore stations. The surveys have provided valuable information on phalarope use of Mono Lake, such as annual populations, responses to fluctuating lake levels, and timing.
However, phalaropes are mobile and can choose where they go–they might choose to visit Great Salt Lake, Utah or Lake Abert, Oregon, two other important staging sites in western United States. To capture the full story, we coordinate our surveys with five other major phalarope stopover sites, Great Salt Lake; Lake Abert; Owens Lake, California; San Francisco Bay, California; and Chaplin Lake, Saskatchewan. At this scale, we can begin to see how phalaropes are reacting to rapid habitat changes—for example, a 35,000-bird increase in Wilson’s Phalaropes at Mono Lake in 2021 coincided with a severe drought at Lake Abert that year. Adding up peak annual totals from all six sites we monitor, numbers of Wilson’s phalaropes ranged from 200,000-300,000 birds total in 2020-2022. This compares to around 500,000 birds recorded in a similar effort in 1986 at the same sites. That could indicate a decline of 200,000-300,000 birds since 1986, but methods differ between the older surveys and the recent surveys. Lake levels have changed greatly which may have driven phalaropes to seek habitat elsewhere. Continued monitoring is needed to understand potential declines.
Ryan Carle, Marcela Castellino, and Kyriana Tarr surveying at Mono Lake in summer 2022. Photo: Ryan Carle
There is reason to be concerned for the future of phalaropes. Their fate is entwined with saline lakes, which worldwide are threatened by water diversion and climate change. Mono Lake is in a precarious situation as the climate in the Sierra Nevada dries, but it does have legal protections and guaranteed water rights. Other lakes are not so lucky: as water diversions and droughts shrink Great Salt Lake, it has shrunk to its lowest level in history and is on the verge of becoming saltier than its invertebrates can handle. 95% of Wilson’s Phalaropes we count are at Great Salt Lake—the fate of that lake and the Wilson’s phalarope are one in the same. Lake Abert, once a large saline lake in southeastern Oregon, dried up in 2021, leaving only trace amounts of local spring water in the lakebed.
People are working hard to secure water for Lake Abert and Great Salt Lake (see Audubon’s Saline Lakes program), but it is a complicated, political process involving a tangle of water rights. We are working to tell the story of phalaropes as a symbol for everything we would lose if we lose saline lakes. A hopeful piece of the phalarope’s story is that the largest phalarope site in South America, Laguna Mar Chiquita, Argentina, was protected this year as the Ansenuza National Park and National Reserve. Half the world’s population of Wilson’s Phalaropes can be found at this site at one time.
Since many of the important phalarope sites are also Western Hemisphere Shorebird Reserve Network (WHSRN) sites, Oikonos is working with the WHSRN Executive Office and others to develop a network of people working on phalaropes and saline lakes throughout the western hemisphere. Strong connections have formed between the communities of Mono Lake and Laguna Mar Chiquita, bringing the phalarope journey to students, leaders, and other community members. As that bond strengthens we hope to connect with additional sites.
Wilson’s phalaropes flying at Mono Lake among the lake’s iconic “tufa tower” rocks. Photo: David Carle
As we work to understand trends, it is important to remember the big picture: saline lake habitat is endangered, therefore, phalaropes probably are too. Next summer, we plan to continue the surveys at these six lakes, while beginning to track the movements of birds with Motus radio transmitters. If you have the opportunity, please spend a quiet moment cherishing a saline lake, while they are with us. With your action and ours they will continue.
You can learn more about our work at Oikonos.org.
Cover Photo: Wilson’s and Red-necked Phalaropes at Mono lake. Photo: Ryan Carle
