It’s generally not newsworthy when new couples move or relocate to the Westside. But these four residents are extraordinary in the sense that they are a rare species, and their decision to set up home locally has scientists and nature lovers excited about the rewards of habitat restoration.
The Ballona Wetlands and the riparian corridor of Playa Vista are two locations where an endangered bird, the least Bell’s vireo, has been spotted nesting over the last few weeks. Both areas are the recipients of intense, public campaigns to restore some, if not most of an ecosystem that has nurtured and nourished a variety of bird, plant and insect species for thousands of years.
The least Bell’s vireo has been seen in the area of Playa Vista and sections of the wetlands for some time but was only recently found building nests, one already dotted with eggs, indicating that the endangered bird might no longer be transitory to the local area.
Dr. Edith Read, a biologist who manages Ballona Freshwater Marsh in Playa Vista, says one reason the birds have begun nesting there is because the physical environment that the least Bell’s vireo is attracted to is now more prevalent.
“The proximity of fresh water has drawn them here,” Read said. “There has been a lot of freshwater habitat here over the years.”
The least Bell’s vireo (Vireo bellii pusillus) has been a federally endangered bird since 1986 and has been listed as a state endangered species by the California Fish and Game Commission since 1980. Approximately five inches long, these small, gray and white birds spend their summers here in the Golden State and winters in Mexico. They are known as migratory birds and have been seen for at least a decade in the region, according to bird experts and local biologists.
Least Bell’s vireo males are known for their distinctive singing, which in combination with other birds has provided the soundtrack for several different species of lizards, insects and other creatures in the freshwater marsh and the bluffs since their nests were discovered last month.
The U.S. Fish and Wildlife Department, which is part of the Department of the Interior, has made an effort for more than two decades to increase the number of least Bell’s vireos. Gjon Hazard, a biologist with Fish and Wildlife in Carlsbad, thinks the songbirds’ decision to nest is a testament to the success of his agency’s recovery program.
Reestablishing conditions where the bird can live, nest and thrive include having a certain species of willow trees, mulefat and other riparian, or being situated near water, plants and trees.
“The proof is in the pudding,” Hazard told The Argonaut. “We have been working with several public and private agencies to restore and improve the habitat for the least Bell’s vireo and therefore increase its numbers.”
Twelve years after it was named an endangered federal species, the least Bell’s vireo has grown from 200 pairs in 1986 to over 2,000, according to the Western Ecological Research Center of the United States Geological Survey. Approximately half of the vireo population resides near the Marine Corps base Camp Pendleton in San Diego.
Robert “Roy” van de Hoek, the lead biologist with the Playa del Rey-based Ballona Institute, on a recent walk in the bluffs just north of Loyola Marymount University saw what he thought was a single male least Bell’s vireo singing on a willow branch. He agrees that the recovery and the restoration efforts of the federal government have been a key factor in the endangered songbirds’ migration to new habitats like the freshwater marsh and the wetlands.
“This is a major success for an endangered species,” van de Hoek said as he walked along Cabora Road below the university.
Van de Hoek said controlling cowbirds, which sometimes take over the nests of least Bell’s vireos and force them out, has also played an important role in the songbirds’ increase in numbers and could be why they are looking for new surroundings.
“Cowbirds can be very aggressive,” the biologist noted. “That’s one reason why the least Bell’s vireo is a very secretive bird that hides its nest away from predators.”
Dan Cooper, a bird expert who works with Read in the freshwater marsh, confirmed that there is a fifth bird above the riparian corridor in Playa Vista.
“They’re birds that like to be near water, and we think that they came to Ballona to nest because of the habitat,” said Cooper, the president of Cooper Ecological Inc. “Part of its DNA is seeking out fresh habitat, so it’s not a total shock that they’re here.”
Van de Hoek said Playa Vista’s rehabilitation of the wildlife corridor, located in Phase II of its development, cannot accurately be attributed to the birds’ decision to nest there.
“They’ve been coming here for years. They would have eventually nested here despite (Playa Vista’s) restoration,” he said.
Van de Hoek, who was one of the first biologists to rediscover the rare Orcutt’s Yellow Pincushion flower in the wetlands near the Marina Peninsula in March, said prior riparian corridors were suitable for nesting, but much of the habitat was removed when Playa Vista began construction of its residential community.
“(Playa Vista) destroyed willow trees there, which might have prevented them from nesting,” he alleged.
Philippa Drennan, Ph.D., who is a professor of plant ecology at LMU, disagrees.
“The habitat may not be perfect, but it’s much better than it was before,” she stated. In order to attract an endangered or declining species, “it always comes back to having the proper habitat, and the riparian corridor and freshwater marsh have been significantly improved,” Drennan added.
Hazard also thinks that the habitat near Playa Vista, as well as in the wetlands, is conducive to the least Bell’s vireo’s nesting needs.
“You have to have the proper habitat in order for them to build their nests,” he said. “This is a sign that good things are going on with our recovery program.”
While there may be disparate opinions regarding the merits of the riparian corridor’s role in inciting the least Bell’s vireo to Playa Vista, there is agreement that Fish and Wildlife’s restoration plan has been a factor in the endangered birds’ seeking out new places to build their homes.
“There is an overflow now in certain areas where habitats of least Bell’s vireo have been established throughout the state, and I think we’re seeing the result of that here,” van de Hoek said.
Read said creating havens for young least Bell’s vireos, which typically breed as first-year adults, is essential as the population expands beyond San Diego and Santa Barbara.
“If you restore the structure, they will come,” Read, who at one time was Playa Vista’s consulting biological consultant, said. “The freshwater marsh and riparian corridor are also providing an insect supply for the least Bell’s vireo.”
The restoration of the marshes and wetlands for a variety of creatures is a part of the larger picture, said Hazard. Now that an endangered species of bird has taken up residence near the wetlands, other species could soon follow, he said.
“(Ecosystems) are intricately connected networks, and it’s very important to have these functioning ecosystems,” the Fish and Wildlife biologist said.
The scientist also agrees that the male least Bell’s vireo, like many rare or endangered species, subscribe to a theory uttered in the movie Field of Dreams: “If you build it, he will come.”