The absence of a peregrine falcon couple from UC Berkeley’s famous Campanile this January has alarmed a group of observers who fear the avian flu has claimed the birds as its latest victims.
Cal Falcons, an organization that has monitored the pair, Annie and Archie, for years has not seen the birds since early January — a concerning sign, as the birds would typically be preparing to lay their eggs and nest, according to East Bay Regional Parks District wildlife program manager Doug Bell.
“She’s a public figure as it were. I can bet people are taking it hard. It’s distressing to us,” Bell said. “The fact that they’ve gone missing would suggest that something tragic has befallen them, perhaps the bird flu.”
Peregrine falcons are the fastest animals in the world, reaching speeds up to 240 miles per hour when dive bombing after prey. But the raptors are notoriously sensitive to environmental changes. Their population once existed across North America, but the prolific use of pesticides such as DDT beginning in the 1940s caused eggshell thinning and embryo deaths, according to a 1989 report by the California Department of Fish and Wildlife. Peregrine falcons ceased to exist east of the Mississippi River, and only two pairs existed in California in the early 1970s, according to East Bay Regional Parks.
In one of the most successful conservation efforts in American history, the Environmental Protection Agency banned DDT in 1972, ruling that widespread use of the pesticide was crippling falcons’ — in addition to bald eagles’ — ability to reproduce. In the decades that followed, peregrine falcon and bald eagle populations have rebounded, and both species have been removed from the endangered species list.
In 2017, Annie the Peregrine Falcon took up residence atop the UC Berkeley Campanile, the world’s second-tallest freestanding clock and bell tower, where she has raised numerous broods with various mates. As Cal Birds waited for her to start a new clutch with her latest partner, Archie, this January, the pair went missing. Bell and the other members of Cal Birds feared the worst.
“We’ve been responding to other incidents of bird carcasses or birds showing up sick around the Bay Area,” Bell said. “It would not be surprising that the bird flu could be the cause of our Cal falcons’ disappearance.”
The latest strain of the avian flu, H5N1, has been highly pathogenic since scientists first observed it in 2022. More than 150 million commercial birds have been forcibly euthanized in an attempt to mitigate the pathogen’s spread, according to the U.S. Department of Agriculture. Wild bird populations have also been hit hard by the virus, and birds of prey have shown particular vulnerability, Bell said.
The most recent annual report on California peregrine falcons, commissioned by the Humboldt Redwood Company, showed a significant decline in territories occupied by the birds since the latest outbreak of the avian flu in 2022. Peregrine falcons occupied 87.5% of their known territories in 2021, but they occupied only half of those just two years later.
While Bell could not definitively state that the avian flu was the reason for Annie and Archie’s disappearance, he said it is highly uncommon for peregrine falcons to uproot themselves from a territory once they’ve embedded themselves.
“They’re more true to their territory than they are to their mates. It’s in their biology to stay in that same territory,” Bell said. “They’re unlikely to leave it unless it’s an exceptional circumstance.”
Bell and other conservationists are unable to track Annie and Archie since peregrine falcons were removed from the endangered species list in 1999 and therefore not subject to trackers that would help environmental groups monitor their whereabouts. Instead, groups like Cal Falcons have served as a watchful eye over the world’s fastest birds.
Even if Annie and Archie don’t return to their hallowed perch above Berkeley, Bell noted that the territory was still a prime location for falcons to call home. Perhaps it could be taken by one of Annie’s offspring that lives on Alcatraz.
“In spite of these recent events,” Bell said, “we’re hopeful that the peregrines will get through this particular epidemic and their populations will recover as soon as possible — because we know their populations can recover.”
