For the first time in the United States, biologists have used a flu vaccine designed specially to protect the endangered California condor.
The problem began in the spring of 2023 when biologists began seeing an alarming number of sick condors around the Vermilion Cliffs in northern Arizona. The birds showed many symptoms humans have with the flu, like lethargy, slow movement and lack of coordination.
In only a few weeks, 21 condors died from a highly pathogenic avian flu. That’s a 20% loss of the region’s total population and a serious setback to recovery efforts.
Condors are vulnerable because they’re social, slow to reproduce and roost and nest in cool, damp cliff crevices that may harbor the virus.
Hoping to control the spread, the U.S. Fish and Wildlife Service received approval from the Department of Agriculture to use the avian flu vaccine.
The vaccine was first tested on black vultures. Then, trials were conducted on a small number of condors in captivity. Through this year, many more have received initial doses, to be followed with boosters. And the good news is some are producing natural antibodies.
The Peregrine Fund, which manages the Southwest population, traps condors regularly to test for lead — still the main cause of mortality. At the same time, they can test for flu, administer the vaccine and see how the birds respond.
So far, the vaccine is offering some protection — better immunity and less severe infections — and saving condor lives.
This Earth Note was written by Rose Houk and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
