Science for a Blue Planet

Featuring cutting-edge work, discoveries, and challenges of our scientists, our partners, and the larger conservation science community.

Strengthening the Strands, One Snowy Plover Flock at a Time

written by Lishka Arata, Point Blue Communications Manager

The Western Snowy Plover, a very cute white and brown beach-loving shorebird, is federally threatened and is considered a species of special concern in the state. California State Parks, US Fish and Wildlife Service, and Point Blue Conservation Science staff conduct field monitoring of this species at Monterey Bay locations. Esther Haile, Point Blue Avian Ecologist, is part of this team and happily shares that, “It’s a great crew that’s extremely passionate and knowledgeable about plover conservation.”

Point Blue Avian Ecologist Esther Haile on a Plover Survey at Monterey State Beach in the fall of 2022. Photo credit: Lishka Arata, Point Blue.

One of the sites that Esther monitors is along Monterey State Beach. She walks the sand with a spotting scope on her shoulder, binoculars around her neck, and a data notebook in her pocket, looking for flocks of plovers she and the entire team have been tracking for years. As she searches she’s surrounded by the complexity of ocean life and death: the harsh calls of terns, the splashing of diving Brown Pelicans, the rise and fall of waves crashing and receding, a decomposing California Sea Lion on the sand, and bits of plastic trash intermingled with washed up seaweed and driftwood.

Monterey State Beach is one of Point Blue’s southernmost Monterey Bay Snowy Plover monitoring locations and it’s part of a swath of key locations that stretches from the Point Reyes National Seashore just north of San Francisco to Vandenberg Air Force Base just north of Santa Barbara. All along that stretch we are partnering with state and federal agencies as well as other non-profit organizations who have shared goals to increase the health and resilience of the beach ecosystems. These are places that define California, provide many economic and environmental benefits, and make the state a beautiful and desirable place to live and visit.

The snowy plover has a unique life history that was designed to help it avoid harm from threats that existed before so many people were on the planet and on beaches. The bird itself, its nest, its eggs, and its chicks are colored in such a way that they blend into the sand on west coast beaches and other shoreline areas making them virtually invisible to the naked human eye. Without ATVs, domestic riding horses, on and off-leash pet dogs, various types of pollution, human-caused climate change, and jogging/walking/playing humans of all ages encroaching on most of the coastline of California, they’d be doing pretty darn well.

How many Snowy Plovers can you spot in the sand here at Monterey State Beach? (answer: there are at least 4). Photo credit: Lishka Arata, Point Blue.

Point Blue’s history with this small, cryptic beach bird dates back to the 1970s when the organization was operating under its founding name, the Point Reyes Bird Observatory. See more about our history with the Snowy Plover in our 2021 newsletter. Biologists–including plover conservation pioneers like Lynne Stenzel, Gary Page, and Dave Shuford–provided the first reliable information on the abundance of Snowy Plovers along the California coast from surveys they conducted during the 1977 to 1980 breeding seasons (March through August is a breeding season, where plovers build nests and raise young). The surveys suggested that the snowy plover had disappeared from significant parts of its coastal California breeding range by 1980. Coast-wide surveys during the summer of 1995 suggested about a 20 percent decline in numbers of breeders along the coast since the initial 1977 to 1980 surveys. Once numbering in the thousands, fewer than 1,800 breeding plovers are thought to nest along the California coast today. Prior to 1970 the coastal population was thought to have nested in over 50 locations in California. Presently, Snowy Plovers nest in only about half as many locations.

Snowy Plover at Pacifica Beach 2021. Photo credit: Jenny Erbes.

When Esther finds her flock, she counts them, notes if they have identifying bands on their legs or not, records the exact location, and writes down a few other details in her field notebook. Esther also documents sources of disturbance and predation, like people, dogs, and crows and ravens. Crows and ravens are the number one predators of plovers at this site. With increased crow and raven numbers due to the growing presence of people and our trash, the balance is off and the plovers get the short end of the stick. Because the plover is a state species of special concern and federally threatened (i.e. its ultimate survival is under threat), conservationists at NGOs like Point Blue as well as state and federal agencies have a mission and mandate to protect the vulnerable species. There have been successful efforts to address the crow and raven problem in recent years, where very targeted efforts were successfully made to remove the crows and ravens that had learned to depredate the plover nests. Esther said the difference in nest success at Monterey State Beach for the plovers before and after the crow removal was like night and day. The year before the  treatment there were five documented nests of which three hatched. The first year after treatment that number jumped to eight documented nests with seven hatching! After her survey Esther enters her observations into a central database electronically and they become part of the species’ conservation story.

As a group effort, Esther and her colleagues are working on educating the public about the harmful effects of disturbance and trash to beach ecosystems, devising science-driven solutions like large-scale habitat restoration to address climate change and biodiversity loss, implementing targeted predator control, and providing reports on population trends based on decades of boots on the ground monitoring to federal agencies in order to influence larger scale policy that could continue to protect endangered and threatened species. Nature is one big connected web which includes our food crops, the air we breathe, the water we drink, and the beaches we enjoy recreating in and on. When one strand of it weakens, it affects the entire network. In order to secure a healthy future we need to keep strengthening each strand and supporting people like Esther who are doing the science. Like she says, “Plovers are just one tiny piece of the web, but a very important one.”