The first time Andrea Jones, director of bird conservation at Audubon California, saw western snowy plovers, she nearly didn’t see them at all. Walking along the high tide line of a Central California beach around 2007, she came across what appeared to be a bunch of gray rocks a couple hundred feet off. The “stones” suddenly stood up, exposing feathered white bellies as they scampered away. The ability to vanish in plain sight is this muffin-size, gray-backed shorebird’s primary defense against predators such as hawks and owls. “Sometimes you can’t see them until you’re almost on top of them,” Jones says.

While the species’ coastal population blends in perfectly among the sparsely vegetated dunes and beaches they inhabit along the Pacific Coast, from Washington State to Baja California, their preference for beachfront real estate with few plants has contributed to their undoing. Invasive plants such as European beach grass have destroyed and crowded the birds’ habitat, as has expanding development, which amplifies other natural dangers, too. In particular, ravens, voracious native predators of plover eggs, have exploded in numbers because they can turn urban food waste into a smorgasbord and concrete buildings into cozy nests.

In the 1980s, these threats slashed the U.S. population of coastal western snowy plovers from an estimated 2,300 to less than 1,500, leading to its 1993 listing as threatened under the Endangered Species Act. (As if that weren’t enough, climate change-driven sea-level rise is projected to shrink many of the beaches they use even further.)

Since then, hundreds of scientists, land managers and volunteers from more than 25 organizations have worked to boost the birds’ numbers, allowing the American population to rebound to roughly 2,300 adults as of 2023. The coastal population must hold steady at 3,000 breeding adults for a decade before it can be upgraded from its threatened status. Because growth has slowed in recent years, researchers are expanding efforts to increase the number of chicks that survive each year and carefully tracking the population’s progress.

As a part of the recovery effort, Matt Lau, a biologist at Point Reyes National Seashore, just north of San Francisco, scours the dunes every summer during breeding season for snowy plover nests. To prevent ravens from poaching eggs, he encases the nests in wire cages with holes large enough for plover parents to freely come and go, and sets up a wider perimeter around favored nesting areas using a knee-high cable to keep people away. If he times it right, he can be close by to attach color-coded bands to the ankles of newly hatched, marshmallow-size fluff balls, to track the birds throughout their lives. Elsewhere in the park, staff are restoring dunes by removing invasive plants, allowing the plovers to reclaim the sand for breeding. Similar efforts are underway up and down the coast.

“It’s a lot of work,” says Jones, who works on western snowy plover recovery with Audubon. “But we put snowy plovers in this situation, and it’s our responsibility to fix it.”

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This article is a selection from the June 2024 issue of Smithsonian magazine

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