Sentinels of Climate Change: Shorebirds in Nevada

By Morrigan DeVito

Shorelines trace the signature of water across the Mojave Desert, brushed with cottonwoods, willows, reeds, and cattails. Dotting that signature are long-legged shorebirds probing the sand with sensitive bills for little insects and other invertebrates to eat. The migration of shorebirds spans across continents, a living memory of where water has marked the West. What are their generations telling us as they move through our landscape?

Shorebird Surveys in Las Vegas

In August of 2022, members of Red Rock Audubon Society (RRAS) gathered at places like the Las Vegas Wash and the Henderson Bird Viewing Preserve to record and count shorebird species for the Intermountain West Shorebird Survey (IWSS). The survey is a conservation initiative led by National Audubon Society and Point Blue Conservation Science with the intent to document changes to freshwater wetlands and saline lakes over the last 30 years. By recording the shorebirds present in these habitats, both volunteers and professional scientists are filling in knowledge gaps about how shorebirds use habitats across the West. This ensures that there is information to guide management decisions that will sustain shorebird populations in the future.

Shorebirds are facing steep population declines across the Western Hemisphere. According to Birdlife International’s 2022 State of the Birds, shorebird populations are declining significantly over the past 40 years. Shorebirds are particularly sensitive to development on wetlands and saline lakes, deeply intertwined with these habitats as they breed or travel thousands of miles on epic migration journeys between the Arctic and Latin America.

Among the shorebirds surveyed in the Las Vegas Valley were sinuous American Avocets, dapper Black-necked Stilts, and wobbly Spotted Sandpipers. But three shorebirds that pass through the valley are species of high conservation concern in the State of the Birds: Lesser Yellowlegs, Long-billed Dowitchers, and Short-billed Dowitchers. These tipping point species may lose another 50% of their population in the next 50 years if nothing is done to help them, putting them in a highly vulnerable position to extinction.

Which Shorebird is That?

Shorebird feathers are mosaics of sand, with flecks of black and strokes of tan, tawny, umber, and pearl stippling their bodies. So for many birders, identifying shorebirds poses a challenge. This is especially true for Greater and Lesser Yellowlegs and Long-billed and Short-billed Dowitchers, whose names indicate only the subtlest of differences between species. Yellowlegs can be differentiated by bill-length and size, with Greater Yellowlegs sporting a bill that is twice the length of their head. But for the dowitchers, vocalizations are the best way to tell the lookalikes apart, and Long-billed Dowitchers flocks proclaim keek-calls.

RRAS member and wildlife photographer David Anderson was one of the shorebird surveyors in August, scoping out the Springs Preserve, Upper Las Vegas Wash, and Henderson Bird Viewing Preserve for all shorebirds present. To those who may be uncertain about their shorebird ID skill level but want to survey, Anderson says,

“Anyone can attend, no matter what their bird ID skills are [...] it was really helpful to have other people to double check the numbers in individual species. Also, it was a low key relaxing morning and I was able to offer identification tricks and tips to the other people on the survey.”

Challenges in Shorebird Conservation

There are big knowledge gaps when it comes to shorebird behavior and movement, and these gaps affect how shorebirds are understood and protected across different states. But the IWSS is a direct response to that. The surveys span stopover habitat, places like freshwater wetlands and saline lakes where shorebirds refuel before reaching their winter or summer grounds, in 11 western states including Nevada, Utah, California, and Arizona.

One of the reasons why there are knowledge gaps is because different states have adopted different protocols to monitor shorebirds. For example, phalaropes, another difficult bird to tell apart at the species level, are monitored very differently between states. At Utah’s Great Salt Lake, the Utah Division of Wildlife conducts aerial surveys and counts large flocks of phalaropes without differentiating species. But at Mono Lake in California, phalaropes are counted by boat surveys at randomized points, so the species are known but not the overall population on the lake. These two styles, while valuable at local level management decisions, paint different pictures when zoomed out to the landscape scale, affecting the understanding of shorebird distribution and response to habitat conditions across the West.

Max Malmquist, National Audubon’s Saline Lakes Engagement Manager, explained that the standardized methodologies and protocols of the IWSS are meant to, “[...] align with protocols used at the landscape scale, such as the Pacific Flyway Shorebird Survey or the International Shorebird Survey, and having standardized protocols allows us to compare and analyze data across the region.”

Matt Flores, the southern region supervisor for the Nevada Department of Wildlife (NDOW), stated that the IWSS gave NDOW the opportunity to monitor shorebird populations in Southern NV, something that hadn’t been done for a few years. It also gave NDOW the chance to align their surveys with the same protocol as other agencies in NV and other states. Long-billed Dowitchers are among the shorebird species prioritized in the Nevada Wildlife Action Plan as species with the greatest conservation needs, alongside American Avocets, Black-necked Stilts, Wilson’s Phalarope, and others.

Collecting standardized data between agencies and states will allow scientists and communities to take the next step in shorebird conservation and better strategize ways to protect shorebirds across the Western Hemisphere. The solutions will look different in different communities and landscapes, but because shorebirds are sentinels of climate change, figuring out their conservation plans will have cascading effects on other issues like climate change and water conservation.

Shorebirds in the Las Vegas Valley: Critical Urban Habitat 

After wintering along balmy wetlands in Latin America, Lesser Yellowlegs are ready to fly North to their boreal wetland breeding grounds in the Arctic. They stuff their bellies with worms, crustaceans, and insects before flinging themselves to instinct, traveling thousands of miles through the night, calling softly to one another under the stars.

The challenges Lesser Yellowlegs face change with the landscape. They are hunted in the Caribbean and have lost breeding habitat in the Arctic as warming temperatures dry up their wetlands. As they navigate the tapestry of mountains and deserts threaded across Western United States, finding water is their biggest concern. They must land, exhausted, in a wetland with ample shoreline so that they can find food before continuing their journey.

One of the places Lesser Yellowlegs land is along the Las Vegas Wash, but it is not as their ancestors would have found it. Once a perennial stream, the Las Vegas Wash is now an urban river coursing past neighborhoods in the Las Vegas Valley, with trail locations from the Upper Las Vegas Wash in East Las Vegas all the way to Henderson’s Pittman Wash. The Wash’s water is primarily treated wastewater, with urban runoff, stormwater, and shallow groundwater in the mix. Since all indoor water use in Las Vegas is recycled through the Las Vegas Wash, which collects and flows through Clark County Wetlands Park and back into Lake Mead, the Wash has become a consistent habitat for Lesser Yellowlegs and other shorebirds.

Local agencies are working to ensure that shorebirds continue to have stopover habitat in Las Vegas. At Clark County Wetlands Park, environmental specialist Ben Jurand explained that the park is working with the Las Vegas Wash Coordination Committee on projects to restore the weirs, which act as water control, at the Nature Preserve and the Mitigation Wetlands past Duck Creek trailhead.

“It has been a few seasons since we have been able to manipulate the water levels,” he says. “The Mitigation Wetlands was originally set up for seasonal flooding in a few of the ponds, so our intention is to restore that functionality and thereby provide better shorebird habitat.”

When water is shallow, Lesser Yellowlegs join throngs of dowitchers, sandpipers, avocets, and other shorebirds as they hurry to feed. Man-made impoundments like those at the Henderson Bird Viewing Preserve (HBVP), where the preserve’s nine ponds are sourced by treated wastewater from the City of Henderson, have become increasingly important for migratory shorebirds. In Anderson’s surveys, he and his team counted 12 shorebirds species at HBVP, including Lesser Yellowlegs and both species of dowitchers. He notes that because a couple of the ponds were kept at lower levels, shorebirds congregated at and feasted on the exposed shoreline.

However, his survey notes a level of uncertainty, marking that it is unclear if water levels at the preserve will be managed this way in the future. But Flores stated that since NDOW has been involved with the City of Henderson, which manages the HBVP, there is potential for the water levels to be managed and lowered for shorebird migration season. If the water is not lowered, this means that during the next spring and fall migration, shorebirds may not have the same habitat and food security, possibly having to travel farther on depleted energy.

Another site that Anderson surveyed was the Springs Preserve, a historic institution often called the “birthplace of Las Vegas”, where springs flowed that attracted early settlers to the valley. Once recharged by an underground aquifer, the historic Las Vegas Springs dried up in 1962 after the city’s population boom and demand for water. Now just past the highway and urban neighborhoods, a trickle of a stream still flows through cottonwood and willow habitat, though it is not favorable for shorebirds because there is not enough exposed shoreline.

“[...] there were no shorebirds seen,” Anderson stated. “[...] but it is important to document how shorebird habitat changes.”

And shorebird habitat has changed significantly. Across the entire region of the shorebird surveys, 7 of the 38 survey sites that historically held at least 1,000 shorebirds every year were completely dry in Aug. 2022. Malmquist stated that in Nevada,

“A large percentage of the historic wetlands and playas [...] were completely dry and provided no habitat, while Las Vegas Wash held 50 shorebirds representing 7 species, and Henderson Viewing Preserve held 125 shorebirds representing 12 species.”

Urban habitat is becoming more important for shorebirds as climate change impacts the availability of water in the desert. Coming into the city may not be ideal for shorebirds, but their adaptability shows that urban wetland and water management has a significant impact on the survival of their species.

Shorebirds Across Nevada

On their way north this season, yellowlegs, dowitchers, and other shorebirds will pass through Important Bird Areas like Pahranagat Valley National Wildlife Refuge in Southern NV and Stillwater National Wildlife Refuge in Northern NV. An Important Bird Area is defined by Birdlife International as having exceptionally large numbers of migratory birds, among other criteria.

At Pahranagat, shorebirds find sanctuary away from the bustling city. Water in the spring-fed lakes at Pahranagat is an echo of what the Las Vegas Springs were once like, where water bubbled to the surface in the middle of the desert. But even here, man-made alterations affect water levels and shorebird habitat. Wildlife Refuge Manager Rob Vinson, who fell in love with shorebirds working in the Bootheel of MI, explains, 

“During spring migration, water levels are the highest and offer the least habitat opportunity for some sandpipers and plovers [...] water levels in some of the marsh fringes are maintained 6-12 inches to allow for larger, wading shorebirds to utilize.”

In the fall, Vinson stated that Lower Lake is allowed to drop to expose shoreline and that North Marsh is dropped to allow large expanses of mudflat “[...] to provide the most diverse shorebird habitat allowing for every niche to be accounted for.”

Up North, Bethany Chagnon, the deputy project manager at Stillwater National Wildlife Complex, participated in the IWSS with the Lahontan Audubon Society to better understand how shorebirds move through the Lahontan Valley. The Stillwater National Wildlife Complex is listed as a site of hemispheric importance to the Western Hemisphere Shorebird Reserve Network as a place where at least more that 5,000 shorebirds stop during migration.

“Connectivity across sites really is critical for these species,” Chagnon says. “With future water shortages across the west, conservation and management of our resources will be vital [...] these issues go beyond what is happening in Lahontan Valley. If we can’t support these populations through all of their life stages, we will keep seeing the same troubling declines.”

How You Can Help Shorebirds

All shorebird habitat is connected, even if it is many miles apart. Shorebirds, while resilient, are still sensitive to climate change. For especially vulnerable shorebirds like Lesser Yellowlegs and dowitchers, finding habitat in Las Vegas on their journey makes all the difference. Although people living in Las Vegas may not see shorebirds in the thousands unless they travel to a wildlife refuge, advocating for public lands, water conservation, and local wetlands still has an impact.

“Connectivity is important, so the work you do in Southern NV makes a difference here,” Chagnon says. “You don"t have to be an expert birder or have a really specialized skillset to help.”

“Reaching out to your local state and federal-level elected officials and asking them to support water conservation policies, state and federal funding is a great way to help protect these critical habitats,” Malmquist states. “Anything that individual members can do to move towards more conservation of water can help. Every drop counts!”

The next IWSS period runs from April 24 to April 30 and will document the springtime migration of shorebirds across the West. According to Malmquist, the surveys will be conducted every spring and fall until 2025. In 2026, National Audubon Society and Point Blue Conservation Science aim to do an in-depth analysis of the data collected and publish the report in a peer- reviewed journal by 2027. The data will then provide foundational information to inform management of shorebird habitat and water conservation policies, such as when and where shorebirds congregate and how the megadrought is affecting them.

“These birds are migrating on faith that something is going to be there for them,” Vinson says. As the signature of water changes throughout the West, how will the story of migrating shorebirds change with it? Will future generations of yellowlegs and dowitchers find enough stopover and breeding habitat in our cities and public lands? The coming years will add more narratives to the shorebird stories. Will we listen?

Photos by Alex Harper