SAVING WILSON'S PHALAROPE
Wilson’s phalaropes are dainty shorebirds best known for their spectacular congregations at large salt lakes in the U.S. West, as well as for their clever feeding behavior and unusual mating system. Unlike most shorebirds, phalaropes spend most of their time swimming and change their feathers — a process known as molting — en route to their wintering grounds.
Natural History
In phalaropes, the typical bird sex roles are reversed: The larger, brighter-colored females pursue males, have multiple mates, compete for nesting territory, and aggressively defend their nests and mates. The male takes on the task of caring for chicks.
Phalaropes eat mostly aquatic insects and crustaceans like brine flies, alkali flies, and brine shrimp. They have a unique technique for catching their food, often swimming in a tight, fast circle to form a small whirlpool, which helps raise food from the bottom of shallow water.
Wilson's phalaropes breed in wetland areas of the north-central United States and south-central Canada and spend winters on saline lakes in South America. During that impressively long southward journey (starting in late summer), these phalaropes make stops at “staging sites” to molt their feathers, stuff their bellies and rest. On their way south, most of these birds congregate at Great Salt Lake in Utah, with other important staging sites including Lake Abert in Oregon and Mono Lake in California. These big salt lakes attract hundreds of thousands of Wilson’s phalaropes, offering a virtually inexhaustible abundance of invertebrates, which the southward-bound birds gorge on to help them rapidly molt their feathers and increase their fat reserves. On their return migration from South America in the spring, Wilson’s phalaropes are less picky about where they stop to rest, using a variety of habitats such as coastal lagoons.
Population Status
Although Wilson’s phalaropes have a relatively large population — about 1 million individuals — they’ve seen dramatic declines that put them all in danger. Thanks to loss of breeding habitat, the species underwent a significant decline in the early 20th century, and since 1980, it has declined by as much as 75% in North America1. Recent surveys at its three main staging sites — the pillars of the species’ transhemispheric range — show major declines compared to 1980s average high counts. At Great Salt Lake, by far the most important staging site, peak counts were one of the lowest on record for the site in 2022.
Threats
Wilson’s phalaropes’ love for saline lakes makes them especially sensitive to threats affecting these habitats.
In the United States, two of their biggest human-caused threats — both of which drain these lakes of water — are diversion of surface water and climate change. In 2022 Great Salt Lake’s water dropped to its lowest-ever recorded level, which increased the lake’s salinity to levels known to impair the survival of invertebrates the Wilson’s phalaropes eat. Lake Abert’s water has almost completely disappeared twice in the recent past, causing major declines in phalarope numbers. Both the Great Salt Lake and Lake Albert are on a trajectory toward ecosystem collapse. Even at Mono Lake, phalaropes’ best-protected saline lake staging site, the water has stayed below the target level for more than 20 years — and its water is still being diverted.
In South America Wilson’s phalaropes’ core wintering habitat falls within a very dry area in the Andes that’s seen an explosion of water-intensive lithium mining development, threatening landscape-scale destruction of these birds’ habitat.
Wilson’s phalaropes are also threatened in their breeding grounds, where their habitat is harmed by agriculture, and between 22% and 46% of their range will probably be lost due to climate change1.
Our Campaign
To save Wilson’s phalaropes from extinction, the Center led a coalition of allies — including author and Center board member Terry Tempest Williams — in petitioning the U.S. Fish and Wildlife Service to protect these birds under the Endangered Species Act. When a species gets protected, the Act requires the Service to draft a recovery plan, which is a roadmap outlining actions to be taken to help the species recover and, eventually, thrive in the wild. The Service must also designate critical habitat to protect the lands and waters the species needs to survive and recover.
The Act requires federal agencies to consult with the Service to make sure any actions they fund, permit or carry out don’t jeopardize protected species or harm their critical habitat. That means that protecting Wilson’s phalaropes could limit federal projects that would drain water from habitats the phalaropes depend on. The Service may also apply protections restricting private or public activities harming the birds — which could, in practice, affect water use around their lake habitats.
Check out our press releases to learn more about the Center's actions for Wilson's phalaropes.