Despite drought-related setbacks, habitat restoration work has the tiny El Segundo Blue Butterfly bouncing back in the Ballona Wetlands
By Gary Walker
The restoration of the Ballona Wetlands may be mired in seemingly endless delays, but nature is not waiting to begin writing its own comeback stories.
The El Segundo Blue Butterfly, a federally designated endangered species, has re-established itself in a small area of the wetlands about a half-mile from a fenced-in preserve in Playa del Rey owned by Los Angeles International Airport.
Sightings of more than 100 of the butterflies have given naturalists and biologists hope that, with the proper habitat conditions, other species may return to the 600-acre wetland, which is slated for a full-fledge restoration by the state Dept. of Fish and Wildlife and the California Coastal Conservancy.
The rare butterflies’ population in the wetlands has steadily increased over the past three years, said nature biologist Irena Mendez. Earlier this summer, naturalists counted 117 of the thumbnail-sized insects where years ago there were none.
“Last year, we did an official count at the height of the flight season and we counted 61 [last] July,” she said. “Between now and the end of this year’s flight season, we are expecting more butterflies.”
The return of the El Segundo Blues coincides with targeted plantings of their sole food source — coastal buckwheat — and environmental conditions in the wetlands that have created optimal breeding conditions, Mendez said.
For the past several years, the nonprofit Friends of the Ballona Wetlands has been restoring sand dune ecosystems by removing non-native plants in wetland areas west of Culver Boulevard in Playa del Rey. The efforts have involved an intensive removal of invasive ice plant in order to allow the native coastal buckwheat to grow, said Friends of the Ballona Wetlands Executive Director Lisa Fimiani.
The larger story of the El Segundo Blue Butterfly has been an optimistic one for several years, but has recently encountered a major backslide, making the species’ return to the wetlands all the more important for its survival.
A 2012 count by entomologist Richard Arnold noted a population increase from about 120,000 in 2010 to roughly 126,000 in the LAX-maintained preserve.
Last year’s LAX survey, however, showed a dramatic decline — an estimated 45,000 butterflies.
“We believe the recent drought has caused the substantial decline in the estimated numbers of the El Segundo Blue population,” Los Angeles World Airports spokesman Marshall Lowe said.
That problem, naturally, can be traced back to the buckwheat.
During her volunteer butterfly surveys in the wetlands, Mendez found El Segundo Blues present a week earlier than expected, also due to climate.
“The rain in March and the warm weather were sufficient for these buckwheat to bloom early,” she said, explaining that the butterflies’ flight season usually doesn’t start until July.
During a recent trip to the wetlands, several of the fragile, typically blue- and orange-tinged butterflies were seen fluttering between buckwheat plants, some of them mating.
There are only four locations in the world where the El Segundo Blue butterfly exists: Palos Verdes, a coastal area along the border of Torrance and Redondo Beach, the LAX preserve and now the Ballona Wetlands.
Mendez, citing a 1991 study conducted by ecologist Rudolph Mattoni, who worked to establish the LAX preserve, said the El Segundo Blue is not a highly migratory butterfly. Therefore, the belief is that the wetlands butterflies moved west from the LAX preserve.
“Since there were no butterflies here four years ago, they would have to have come from the LAX dunes,” Mendez said.
Fortuitous winds may have also played a role in getting the El Segundo Blues to come north. Mattoni’s report had envisioned the wetlands in Playa del Rey as a potential repopulation area, but found that the butterflies seldom travel more than 650 feet in search of food sources.
Naturalist Tracy Drake, who photographed an El Segundo Blue in the wetlands on June 30, has been involved in guiding the butterfly survey efforts in the wetlands and is ecstatic about the new numbers.
“It shows that restoration really works,” said Drake, the manager of the Madrona Marsh Preserve Center in Torrance.
The El Segundo Blue is not the only species that has made a comeback in the wetlands.
A male and female California gnatcatcher, a bird that had been listed as a threatened species by the U.S. Fish and Wildlife Service for 20 years, were seen last year in the wetlands and have since had babies.
The Orcutt’s Yellow Pincushion made its colorful return in 2009 to the Ballona Peninsula, where scientists say it had not been seen in over a century. The dune flower is listed as a “1.B.1” by the California Native Plant Society, which means the flower is rare, threatened or endangered. Several were also later found in 2011 near the area of the wetlands in which the El Segundo Blue appears to now be flourishing.
The Least Bell’s Vireo, a native bird considered an endangered species, returned to the area in 2010, building nests in the freshwater marsh at Playa Vista and in the Ballona Wetlands west of Lincoln Boulevard.
“We can definitely say that the restoration work in the western dunes has brought back the El Segundo Blue Butterfly. They need a very specific plant, dune buckwheat, to survive, and the Friends of Ballona Wetlands have actively planted that species to give the endangered butterfly additional habitat,” said Karina Johnston, a restoration biologist and watershed programs manager for the nonprofit Bay Foundation. “The Least Bell’s Vireo has used the restored riparian corridor, so planting natives there and restoring the corridor likely had some positive effects on the vireo.”
The female El Segundo Blue lays between 80 to 100 eggs within a single flower, said Mendez. After the eggs hatch, the caterpillars feed on the flowers’ pollen and begin metamorphosis. As larvae, they burrow underneath the buckwheat to emerge from underneath the plant in spring and transform again into butterflies.
Mendez hopes the butterflies’ growing numbers will inspire wider support for restoration efforts.
“I think the potential for education and the realization that the coexistence of an endangered species with humans in an urban environment is happening here is a very important story to tell,” she said.