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Shaela Adams
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The Monumental Effort to Understand Migrating Shorebirds

 Audubon > News Read More 

This past April, more than 300 participants gathered at over 200 wetland sites across 11 states in the Intermountain West, armed with binoculars and spotting scopes, joined together for one purpose: to survey shorebirds. Facing inclement weather and an overwhelming sense of urgency to time their effort to capture peak migration perfectly, the data collected will contribute to a much larger effort—the Intermountain West Shorebird Surveys (IMWSS or surveys).

Initiated in the Fall of 2022, the Intermountain West Shorebird Surveys are a monumental endeavor to map out the distribution and abundance of migratory shorebirds as they move through the interior portion of the Pacific Flyway in hopes the results will help wetland managers across the country to sustain the wetlands shorebirds depend on, even in an age of changing water systems.

The Pacific Flyway—a bird highway running from the Arctic in North America to Tierra Del Fuego on the far tip of South America—is essential to shorebirds. Some 30 common shorebird species winter and breed along the flyway—including as high as the Arctic. Spanning more than 9,000 miles, their journey is long, leaving shorebirds reliant on saline lakes and other wetland ecosystems across the Intermountain West for critical stopover points during both spring migration (to build energy) and fall migration (to molt their feathers).

The IMWSS project takes advantage of these stops, giving surveyors a chance to count a significant portion of the far-flying birds as they funnel through these stopover points in their journey. Peak migration periods are short though, lasting only one to two weeks, and organizing such a large number of volunteers and biologists to survey such an expansive range of sites is an immense lift. Despite analyzing trend data from eBird and Audubon’s own science team, hitting the peak of all shorebirds in spring and fall isn’t always perfect.

Which all begs the question: why such a monumental effort for such small birds? Especially considering they’re not keystone species within the food systems which they move through?

“Migrating shorebirds are indicators of ecosystem quality at a grand scale—they tell us how Earth itself is doing,” said Blake Barbaree, a Senior Ecologist with Point Blue Conservation Science and one of the lead coordinators of the Intermountain West Shorebird Surveys.

Blake joined Point Blue Conservation Science in 2012, working almost exclusively on the research and monitoring of migratory shorebirds. Among other endeavors, he’s coordinated Point Blue’s monitoring project of shorebirds covering the Pacific Coast of the Americas from Alaska down to Chile for the past ten years.

Point Blue also works with the Pacific Flyway Council, a consortium of state and federal agencies collaborating and supporting migratory bird needs at the large-scale flyway level. As Blake engaged with the Council through his coastal monitoring work, it became evident that there was a significant data gap when it came to shorebirds in the interior portion of the West.

“Our coastal monitoring program is primarily focused on wintering populations that congregate in coastal locations, so important sites between the Rockies and the Cascades have been left out for the most part,” he explained.

And while there are other monitoring programs, such as Manomet’s International Shorebird Survey, they primarily cover shorebird populations in the Midwest and East Coast.

“There was this gap within and around the West and very little work to understand migratory shorebird populations beyond Shuford’s project thirty years ago that Point Blue and Audubon are now working to replicate,” said Blake.

Blake isn’t the first scientist at Point Blue to come to this realization. Point Blue, formerly known as Point Reyes Bird Observatory, conducted the first and only, comprehensive shorebird surveys of the U.S. portion of the Pacific Flyway 30 years ago that covered inland wetland sites across the Great Basin under the leadership of former Senior Scientist, David Shuford, who retired in 2019.

“Very little work has been done to understand those populations since the original surveys. We wanted to leverage all of that work to not only replicate a similar monitoring program today, but also have the ability to look back and compare the new information to what was gathered 30 years ago,” said Blake.

While it was already a massive undertaking 30 years ago, the scope of the project has only magnified as survey sites today include not only the original 162 sites, but more than 50 additional sites. Simultaneous surveys over such a broad area requires a collective that was two years in the making and would be impossible without the large number of volunteers contributing to the project.  

“We couldn’t do it without volunteers, especially those participating from Audubon’s network of chapters across the West, but we also couldn’t do it without the biologists.  It takes everyone.”  

While it varies by season, this new survey effort has built out a full partnership network composed of more than 70 organizations, including National Audubon Society, and 300 participants, of which two-thirds are volunteers and the rest professional biologists. Of the 200+ sites in the network, the vast majority are on some kind of publicly managed lands—including more than 40 sites on federally managed national wildlife refuges, and a significant number on the lands managed through 11 different state wildlife agencies. Such a level of coordination and collaboration is often not the standard, but it’s needed here because of the massive scale of migrating shorebirds.

“Most science ends up working in a bit of a bubble to an extent, whereas working through huge networks to survey and meet the challenge of meaningful science for migratory birds requires collaboration at a scale that is unthinkable for most in the scientific community,” said Blake.

And while some volunteers only survey one site during each migration season, others such as Blake work tirelessly to survey as many sites as possible during each window.  

Moving northward with the birds, Blake started this spring’s surveys at the Salton Sea in southeastern California and then moved north to the Southern Oregon-Northern California wetland region that includes numerous crucial sites for migrating waterbirds.

“I hope at the end of this that we can have something meaningful that is useful for decision makers to use, and if we do, we’ll have collectively made an impact at the end of this project. And that collective impact is a huge part of the Intermountain West Shorebird Survey story.”

The power in replicating a survey at this scale is the ability to compare data—comparisons that will hopefully shed light on how the abundance of shorebirds may have changed at individual sites, at the regional level, and also how their distribution has changed as the different water systems have changed over the past 30 years.

Water systems across the West have experienced significant changes in the past few decades, in part from climate influences, but also from management and human use, impacting different water basins in different ways. National Audubon Society published a report in 2017 entitled “Water and Birds in the Arid West: Habitats in Decline” highlighting the changes in many of these water systems, and has been instrumental in driving conservation of wetlands—including saline lakes—that continue to support ~90% of shorebirds migrating through the Intermountain West despite steep declines. In addition to backing the need of the Intermountain West Shorebird Surveys, it has helped drive conservation efforts like the federal legislation “Saline Lake Ecosystems of the Great Basin States Program Act” that created the USGS’s Saline Lakes Integrated Watershed Availability Assessment program.

On the other side of the coin, there have been different levels of conservation on wetlands and different regions, changing water dynamics and hydrologic basins.

And yet, surveyors are finding that even with changing water dynamics shorebirds have the innate ability to not only detect habitat but respond and adapt to habitat change.

To put it plainly, if there is water, birds will come.

“This spring, the Lower Klamath Wildlife Refuge had water for the first time in five or six years,” Blake said, detailing how in Shuford’s original survey these refuges were some of the more important places in the flyway, but have since gone almost entirely offline. “We’re talking bottom of the priority ladder now, and yet, not only did they have water this spring, but we also counted 8,000 shorebirds.” 

Despite the generational absence of habitat for most of these birds, there is an immediate response the moment water returns. Klamath isn’t the only site surveyors have witnessed a return of habitat, and therefore a return of shorebirds.

Owens Lake in California has been infamously dry after water diversions to Los Angeles in the 1970s completely emptied the basin. Before these diversions, Owens Lake was a well utilized habitat for shorebirds. The dry lakebed has resulted in catastrophic dust events, leading the state to spend billions on dust mitigation. An unintentional benefit of the dust mitigation efforts? New shallow wetlands.

“The original Shuford papers outline how degraded Owens Lake had become with hardly any birds,” Blake said. “During the past two fall surveys, an average of around 25,000 shorebirds were using the intentionally created wetlands for wildlife and dust suppression.”

Blake and partners like Audubon hope that the insights gleaned from case studies such as these sites will help aid water managers to better manage their own wetlands. If we can understand how distribution has changed over time, we can better understand how management can create additional habitat. And while the IMWSS is still two years from being complete, many involved are already sharing their findings.

Just this month, Blake released a new summary of data that’s been collected thus far. While the summary is not an analysis, in part because we’re still building the sample size needed to start analyzing and drawing any conclusions, the numbers are already starting to tell a story. 

“There is evidence that Great Salt Lake and Salton Sea remain two of the most important sites, just as they were 30 years ago, even with varying shorebird counts recorded during the last three survey windows. Other larger sites are having lower rates of decline while some of the smaller sites are entirely offline or dried up,” said Blake.

When the surveys wrap up in 2026, Point Blue and Audubon are aiming for a peer-reviewed paper, like the original Shuford Paper, and ideally a few more analyses that will provide additional details on individual sites or species. Blake and team also hope to work through the Pacific Flyway Council and State and Federal wildlife agencies to have migratory shorebirds better addressed within both state and federal wildlife plans as potential species of conservation focus.

“It’s really challenging for some states to be able to incorporate migratory species that may only be passing through their state for portions of their life cycle,” Blake said, explaining that with so many species present in each state, most state-level plans need to prioritize species that reproduce or breed within the state.

“It’s really challenging, and inherently there’s very little robust and useful scientific information for managers to rely on and use to make decisions. We’re hoping through this survey we can highlight changes at the species level, not just the entire taxa or group of shorebirds.”

Thinking about individual species may prove beneficial over time for identifying species that may need more help than others and need to be considered for some type of conservation designation. The prospect of this benefit alone is enough for those involved to continue in the monumental effort that is the Intermountain West Shorebird Surveys.

Community science is only possible with volunteers, and we need your help!

Email: Blake Barbaree at [email protected] or Max Malmquist at [email protected] to join the effort this fall and find the survey location closest to you. 


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