Citizen scientists, partners to document California brown pelicans population declines

Credit: David Pereksta, for USFWS

By Ashley Spratt
Updated October 13, 2016

The U.S. Fish and Wildlife Service is partnering with the Audubon Society and Cornell Lab of Ornithology to host a West coast-wide citizen science survey to count California brown pelicans on Saturday, October 15, 2016.

The count is happening during the last four hours of daylight to help conservationists determine the health of the iconic species. Data collected from this survey will help scientists and researchers understand how threats to the species, like changes in weather patterns and prey availability, could impact pelican populations over the long term.

“Data collected in both the spring and fall will help us understand breeding activity over time,” said Robert McMorran, fish and wildlife biologist with the Service’s Ventura Fish and Wildlife Office. “During the spring, the pelicans are likely to be at their breeding locations, like the Channel Islands. During the fall, we would anticipate higher numbers at roost sites along the coast. With data collected at both times of year over time, we will be able to document results of past breeding seasons, based on the number of juveniles and adults present on the breeding islands and the coast.”

Credit:  David Pereksta, for USFWS


There are two ways for the public to participate in the citizen science survey. Birdwatchers can find an established group on the survey website and contact the roost coordinator, or interested individuals can visit any site along the coast, during the same time frame, and report their observations through a portal in eBird, an online database of bird observations providing real-time data about bird distribution and abundance.

“People who care about pelicans really stepped up to make the kickoff survey in May a big success, showing this survey will succeed over time in providing information critical for understanding and protecting this amazing seabird,” said Anna Weinstein, marine program director at Audubon California. “We are so grateful for the interest and enthusiasm of folks up and down the coast.”

About the Brown Pelican

The California Brown Pelican subspecies (Pelecanus occidentalis californicus) was removed from the Endangered Species list in 2009. The most recent population estimate is 70,680 breeding pairs.

The majority of the subspecies breeds in the Gulf of California, Mexico; 15-20 percent of the population breeds at the U.S. Channel Islands. In recent years Brown Pelican productivity at the Channel Islands and across the range has been poor, and key forage species including anchovy and sardine have collapsed raising questions and concerns about recruitment to the breeding population and ultimately the health of the subspecies.

The survey will be conducted by Service biologists and our partners, as well as volunteers, like those shown here during the annual Bay Area "Hawk Watch" in 2014. Credit: Terrie Schweitzer

The Service is also dedicating $120,000 in funding to support a five-year survey from 2016-2020 of California brown pelicans at the Channel Islands – home to up to 20 percent of the breeding population.

California brown pelican populations plummeted in the 1970s due to the impacts of DDT and other pesticides in the environment flowing from mainland sewers into the ocean, contaminating the pelicans’ fish prey base. When the pelicans ate contaminated fish, DDT altered the birds' calcium metabolism, resulting in egg-shell thinning and ultimately reproductive failure.

Credit: Mike Long/USFWS

In 1970 only a single chick survived out of 552 nests at the U.S. Channel Islands’ Anacapa Island off the southern California coast. That same year, the species was listed as federally endangered. DDT was banned in 1972, and so began the fight to save the California brown pelican from extinction.

The U.S. Fish and Wildlife Service published a recovery plan for the species in 1983, and strong increases in both productivity and nest attempts were observed in the mid-1980s. From 1985-2006 the Anacapa Island nesting colony produced a mean of 4,600 nests each year.

California brown pelicans are an iconic species for
communities along the Pacific coastline.  From
Washington to California, these animals play
important roles in our coastal ecosystem. Pelican
populations are closely linked to their food source
populations along the Pacific coastline. During
their breeding season, 90 percent of the California
brown pelican’s diet consists of northern anchovy,
but they also feed on Pacific sardine and Pacific
mackeral throughout the year. Photo Credit: USFWS

In 2006, the Service estimated the entire California brown population at around 70,680 nesting pairs, equating to 141,360 breeding birds.

Due to this remarkable recovery, in November 2009, the California brown pelican was removed from the endangered species list, but remained protected under the provisions of the Migratory Bird Treaty Act.

Since delisting, conservation partners including the California Institute of Environmental Studies, National Park Service and other organizations have collected intermittent population data on brown pelican populations, however, funding for comprehensive monitoring efforts has been limited.

Through those surveys, scientists have observed poor productivity of brown pelicans on Anacapa Island at the Channel Islands and across the species’ range. Changes in the population of key forage species including anchovy and sardines raise questions and concerns about the health of the breeding pelican population.

Although numbers suggest a population decline, this limited data does not necessarily indicate a long-term trend. By collecting this important data, scientists hope to understand how potential threats from changes in weather patterns, to changes in prey availability, changes in habitat or contaminants, could impact California brown pelican populations over the long term.

“Working together we can take steps to determine the stressors impacting California brown pelican populations. With support from Audubon chapters, local birding groups, communities, and the general public, citizen science surveys like this one can contribute to solving real-world conservation problems,” Lohoefener said.

Credit: Mike McCrary, for USFWS

Ashley Spratt is the public affairs officer for the Ventura Fish and Wildlife Office.

[Note: This article was originally published in October 2015. It is updated here to announce this year's survey activities.]