Bird-watchers are intrigued and delighted that high-diving seabirds known as blue-footed boobies are being found across Southern California and as far north as Marin County in recent weeks.
Blue-footed boobies, which rarely venture north of Imperial County's Salton Sea, are suddenly "all over the place," said Kimball Garrett, manager of the ornithology collection at the Natural History Museum of Los Angeles County.
Members of the large bluish-gray species with a long serrated beak, absurdly short legs and bright blue webbed feet have been spotted more than 30 times recently. They include six seen relaxing on the breakwater at Marina del Rey.
A similar wave of the birds hit Los Angeles County beaches, lakes and streams in the early 1970s.
"This is the first invasion of boobies since the numbers of birders have swelled," Garrett said. "So, there's a lot of happy bird-watchers seeing them for the first time."
Some scientists are wondering if the visiting boobies are somehow related to a recent series of distressing biological mysteries in Southern California's coastal waters.
The National Oceanic and Atmospheric Administration is trying to determine whether a sudden reduction in sea lion pups in 2012 was linked to a dearth of sardines and anchovies that year. In the Channel Islands, the reproduction rates of the only breeding colonies of brown pelicans in the Western United States have plunged since 2010, a year after the bird was removed from the endangered species list. In August, at least three brown pelicans were found dead in Malibu Lagoon.
"There's a lot of weird things happening out there," Dan Anderson, a professor of wildlife biology at UC Davis, said. "No one is sure of what the cause is."
On Tuesday, Audubon California, the Center for Biological Diversity and the Pacific Seabird Group called on the U.S. Fish and Wildlife Service to assess the status of the brown pelican and potentially related factors such as climate change and supplies of forage fish near breeding islands.
As for the boobies, bird experts speculate that the birds, most of them juveniles, may have been driven north in search of prey fish.
The sightings include one reported to Los Angeles Animal Services after the bird was found waddling along a sidewalk near 2nd and West Slauson avenues south of downtown. On Tuesday, the emaciated juvenile was recovering in a spacious waterfowl pen at the International Bird Rescue Center in San Pedro, gulping small fish by the dozens.
"He's still really skinny," Kylie Clatterbuck, a rehabilitation technician at the facility, said as the booby preened nearby. "We're going to fatten him up a little bit, then find a nice spot to release him."