Little Birds, Big Purpose

On the coast of Whidbey Island, researchers and community scientists are using pigeon guillemots to learn about the condition of the birds’ environment.

Story by Cooper Castelle | Photos by Linnea Hoover

June 12, 2021

It’s 7:30 a.m. on a cool spring morning at Whidbey Island’s Penn Cove and the team of community scientists is almost ready. Herons, seagulls and sparrows soar above as a harbor seal drifts lazily along the coast. Birds chirp as waves gently lap the shore and the briny smell of the Salish Sea fills the air.

In the distance, a group of crow-sized black seabirds with white-tipped wings and bright red legs fly over the beach, swim in search of food and rest on floating logs. Known for their playfulness and prevalence in the Puget Sound, these birds are no ordinary deep-sea divers: They’re pigeon guillemots.

Team leader Kris Holley is busy pointing out various burrows to volunteers. It’s late May and the pigeon guillemot breeding season has just begun. Armed with survey sheets for data collection, binoculars and soft blankets to sit on, the community scientists prepare for a day of observation.

Since 2004, Frances Wood, founder of the Salish Sea Guillemot Network, and her teams of volunteer community scientists have been combing the beaches of Whidbey Island in search of pigeon guillemots. Labeled an indicator species due to their abundance and accessibility, these small Pacific Northwest seabirds represent the wellbeing of their surrounding ecosystem. Community scientists are able to inform professional researchers about the birds and their current activities by recording the birds’ diet and breeding habits.

“I want everybody in Puget Sound to know what a pigeon guillemot is,” said Wood. “It’s not a pigeon.”

The Puget Sound Partnership was created to improve the Sound’s ecological health by 2020. Researchers involved in this project recognized the value of birds as indicator species, and seabirds like pigeon guillemots were chosen based on their abundance and ecological importance. The community scientists who gather data on these birds are often interns or retirees.

“The data were really informative,” said Scott Pearson, a senior research scientist specializing in seabirds at the Washington Department of Fish and Wildlife. “I think it’s a nice example of citizens getting very involved.”

During the hour-long surveys, everyone remains quiet and still to avoid disturbing the birds. After recording the date, time and tide levels, the community scientists begin their observations. All disturbances must be recorded: Dogs, boats and beachgoers can force the birds to abandon their activities. While seagulls may not pose a threat, bald eagles certainly do and pigeon guillemots know it.

The community scientists record all burrow visits, as well as what food is brought back to the nests. Unlike most seabirds who use their beaks and feet to dig burrows into the ground, pigeon guillemots typically nest in pre-existing burrows dug by other birds.

An occupied burrow is where a pair has begun nesting and the female has laid at least one egg, according to scientists. Burrow occupancy is important to monitor because it can reveal potential population and breeding changes to come. Sometimes these shifts reflect short-term events, like particularly warm years. In other cases, they can represent long-term population changes.

When ocean temperatures along much of the west coast of North America spiked between 2013 and 2016, volunteers saw fewer burrows occupied. Another local seabird species, the rhinoceros auklet, saw a 30% decrease in burrow occupancy during this time. The heat wave likely led to a lack of food, reducing the auklets’ ability to breed, according to Pearson. When the water eventually cooled off a couple years later, breeding rates returned to normal.

Marine heat waves can disrupt fish populations, which means less food for seabirds like pigeon guillemots, who eat underwater organisms such as gunnels– wormy, eel-like coastal fish– and sculpins– small, lanky fish with big, wide heads. According to Whidbey Island’s community scientists, gunnel populations are currently decreasing whereas sculpin populations are increasing.

Some local seabird species, such as the elusive marbled murrelets, are declining rapidly. Oil spills, deforestation and commercial fishing are all factors behind this trend. Pigeon guillemots have proven more durable. Their numbers in Washington — estimated at 4,000 to 6,000 birds — have remained relatively stable in recent years, though it is likely their numbers have decreased in recent decades, according to the Seattle Audubon Society.

“If something is happening to the pigeon guillemot, you know that something is bad,” said Emily Buckner, a graduate student at the University of Washington who recently conducted a study on the dietary shifts in breeding pigeon guillemots. “These are species that should be able to withstand slight variations.”

Climate change alone threatens more than two-thirds of North America’s bird species, according to a recent report by the Audubon Society. Of the 389 species listed as vulnerable to extinction, nearly 150 may be saved if global warming remains below 1.5 °C. These species include birds native to Washington state such as the American goldfinch and the red-breasted nuthatch. Community scientists continue to provide data that researchers need if threatened bird species are ever to make a comeback.

“It’s really easy to want to get in your hidey-hole and just run away from it all, but I highly encourage people to reach out to people in their community that are doing good work,” Holley said. “You can always find people that want to make a difference.”

As the morning’s survey ends, the community scientists reflect on their observations. It’s now 9 a.m. and the sun is beginning to fight the clouds. Everyone is in good spirits as they prepare to leave the beach.

“Once you know something, you begin to understand it, and once you understand it, you begin to love it,” Holley said. “Once you love it, you want to protect it.”

Cooper Castelle is an environmental studies student at Western who is interested in the relationships between people and the natural environment.