There is a steady trickle of birds from across Southern California being brought to rescue centers like the one in Orange County. McGuire and others consider the usual culprits that cause injuries among birds, such as paralytic shellfish poisoning and domoic acid toxins from algae blooms.
"I don't know what's going on," McGuire said. "It's so hard to keep count in the past few days. What day is it?"
In 2010 and 2012, Southern California veterinarians saw a similar crash among the brown pelican population that stretched over several weeks. Around that time, rescue centers saw more young birds in distress, but the latest batch includes older birds. A similar event happened in 2018, but not at the current scale.
"Getting a large number of hungry young birds is sometimes more normal and it can also be a sign of something problematic in the environment. But the fact that we're getting all ages of birds and that this is hitting all pelicans equally, you can almost rule out the young bird inexperience factor," Bergeron said.
Rescue centers are scrambling with limited funds to feed and nurse the brown pelicans and workers can't help but wonder what dire warnings this all points to.
"We definitely need to be paying attention and do what we can for the birds right now. And also think about what the big picture is that humans should be concerned about as well," Bergeron said.
Nearly 60 years ago, the California brown pelican was on the brink of extinction. The now-banned pesticide DDT weakened the birds' eggshells, making them so brittle that nesting mothers would crush them.
Anacapa Island in Ventura County is one of the birds' main roosting sites in the United States. In 1970, just one pelican chick was successfully born in captivity on the island, and that same year the federal government listed the bird as an endangered species.
Conservation efforts, and the ban of DDT, helped the bird's population rebound, and by 1985 researchers counted nearly 6,500 newborn pelicans at Anacapa Island. By 2009, the population soared and the bird was taken off the endangered species list.
State officials expect to have more answers in the next few days about what is happening to the brown pelican.
Bergeron said that sometimes rehabilitated birds are released hundreds of miles from where they were found to give them a chance to thrive in a new habitat. But it's still too soon to say how far the current crash is spread across California.©2022 Los Angeles Times. Visit at latimes.com. Distributed by Tribune Content Agency, LLC.