Why birders travel from all over to see Sacramento’s yellow-billed magpie

This year, his population survey was spread over 15 sites throughout Sacramento County. He counted 850 yellow-billed magpies at the sites and says that amounts to a 30% recovery since his surveys began. He ventures out to do this work every nesting season, which is late winter for yellow-billed magpies. 

While Airola mostly conducts these surveys on his own, he’s also sometimes had the help of his daughter, Layla. And over the years, his passion for the species has grown.

“I think it should be the state bird instead of the California quail,” Airola said. “But that’s very controversial.” 

His work offers some insight into how their population has started to recover after being hit hard by the West Nile Virus in the mid-2000s. CapRadio’s Manola Secaira joined Airola and his daughter Layla at Discovery Park, one of his survey sites, to learn more about the bird’s recovery and where to find them. 

This interview has been edited for length and clarity. 

Yellow-billed magpies are really unique to the region that we live in. Why is that?

The yellow-billed magpie is what's called an endemic species to California. So, it is one of only two species that occurs in the state of California that has never been seen outside the boundaries of California. It is truly a California native. 

They are also genetically separate. They were isolated from the larger population of the black-billed magpie, which occurs throughout the west on the east side of the Sierras and to the north of the Cascades.

But this population became isolated. It became a separate species. It adapted to our hotter climate and different conditions in the Central Valley and the Central Coast of California. 

It's interesting to see how they live together with man, which they do very effectively or have done very effectively up until West Nile virus took them out. 

A yellow-billed magpie seen through tree branches Thursday, March 20, 2025, at Discovery Park in Sacramento.(Gerardo Zavala/CapRadio)

Why are these yellow-billed magpies particularly sensitive to that disease?

Well, the magpie is a corvid and the corvids are particularly susceptible to West Nile virus.

So when it arrived, the crows, the jays, the magpies and then several other species declined dramatically. The yellow-billed magpie population decreased by about 85% within just a year or two after West Nile virus arrived. You [could] find dead magpies laying around all over the place here at that time.

Then, for unknown reasons, the other corvids — the jays and the crows — recovered. They developed resistance to the disease, the West Nile virus disease. But the yellow-billed magpie has been very slow to accumulate that resistance.

And then in 2020, you came in and started this population survey. 

Well, my study sort of began as a field project to go learn what I could learn. And as I learned about the population and I began looking year to year to year, I realized I [could] start tracking what changes are occurring in the population — Is it continuing to decline? Is it staying stable or is it increasing?

What I found is that since 2020, the population that occupies the Sacramento Metropolitan area has increased by an average of 6% per year over that six-year period. We're up about 30% in terms of numbers.

So, the magpie is coming back slowly — more slowly than others, but at least in the urban area where I've been studying, the population is coming back.

The reasons that the magpie may be coming back here would be that they are slowly developing resistance, but it does appear to be slow. You know, it's an evolutionary process. 

The other possibility is that they're doing better here because in human environments like our urban areas — these parks that I'm studying them in are surrounded by urban areas — the mosquito abatement programs are intensively controlling mosquitoes, which may be just incidentally protecting or assisting magpies by lowering the amount of West Nile virus in the population. Until we get data, blood samples, and look to determine if resistance exists in the population, we won’t know for certain. 

A yellow-billed magpie flying over Discovery Park Thursday, March 20, 2025, in Sacramento.(Gerardo Zavala/CapRadio)

I’ve heard that birders from all over come to the Sacramento region to see this bird. You’re a member of the Audubon Society — have you noticed that? 

If you're going to get a magpie, you have to come here. So there are a lot of people from all over the U.S., North America and even the world that come here to California. They're coming, in part, to get [a look at] these unique species, one of which is the yellow-billed magpie. 

Many times during the season, I'll get these calls: “I really need to see a yellow-billed magpie. Where can I go? Does anyone know where I can see one?” And to some of us, it's kind of funny because they're very common if you go to the right place here. 

Discovery Park [is] the area with the largest population of yellow-billed magpies. There are about 250 birds nesting here this year. So I send everybody to Discovery Park and then they're happy. They find their bird.

But other parks include Howe Community Park, Ancil Hoffman Park, William B. Pond Recreational Area on the American River. Any of these parks along the river that have areas of turf, you're going to find magpies there.

What has made this species an interesting one to study?

A lot of the reason that we didn't have a lot of research on the yellow-billed magpie before I started my work here in the Central Valley is because they were so common. People thought it wasn't worth really studying, I guess. When we had the big decline, suddenly it became, oh my gosh, we better know more about them. And there was surprisingly little done.

The only studies that were ever done were done in the Central Coast region but almost nothing on the Central Valley population.

I feel good that I've been able to add to that knowledge base for our Central Valley birds. I have kind of a paternalistic attitude toward magpies in general because they're clever, intelligent, pretty to look at, interesting to watch.

It’s impressive that you’ve been able to do this as a mostly one-man operation.

AIROLA: I have mostly done it myself. My daughter helped me before she went off to college.

LAYLA: It's a good opportunity to spend time together. Sometimes having your dad boss you around and tell you like, oh, count this, count that. [I’m] like, "Oh, stop telling me what to do." But… it’s a fun experience. I think overall, it's good to recognize and learn more about the birds that are in the area that you live in, and to appreciate them.

AIROLA: It gets me out walking and being in nature. And you know, I'm relatively low-tech. I have a clipboard and a pair of binoculars and a ballpoint pen, a few maps. That's pretty much all I need to do this study. There's a lot of opportunities for people to contribute in that way without being a big fancy scientist with large research budgets.