Catching Up With Our California Endemic: The Yellow-billed Magpie

I see them pretty much every day, so it's easy sometimes to forget that this is an exceedingly rare bird. There are less than 200,000 of them in the world, which is not all that many for a species that is faced with habitat loss, and an exotic disease. The Yellow-billed Magpie (Pica nuttalli) is also one of California's few endemic bird species.

If you are a non-Californian, you might look at this species and think it is just a magpie (the Black-billed Magpie), but it is a distinct species, and the ranges of the birds rarely overlap. The Sierra Nevada is the barrier that has provided the isolation allowing the species to diverge.

I live and work in prime magpie habitat. They range over the Coast Ranges and Central Valley of California, living off of bugs, grains, and pretty much any kind of food they can find. They are gregarious, often flying about in flocks, and engaging in boisterous arguments. A day at work would be lonely without their calls going on in the background.

The arrival of the West Nile Virus was nearly their undoing in the early 2000s. They were particularly susceptible to the viral infection because of their gregarious nature, and more than half of them were lost. The few birds with natural resistance have survived and have allowed the population to slowly rise again.

These pictures are some I've collected this year from the MJC West Campus and the along the Tuolumne Parkway Trail where I most often see the birds. I'm glad they survived their version of the bubonic plague. The state would be a less interesting place without them.

Close Encounters with a "Rare" Bird: Yellow-billed Magpie on My Campus

I sometimes have to remind myself that I'm privileged here in California to see a rare bird on a regular basis. There are hundreds of thousands of birders across North America and the world who never get to see a Yellow-billed Magpie (Pica nuttalli). I sometimes see dozens of them on a given day, since there is a good-sized flock on my campus of Modesto Junior College. The reason of course is that they are found in only one small part of the world, the Great Valley and Coast Ranges of California. They are one of the very few truly endemic birds in California. There are probably not much more than 100,000 of them in existence due to a devastating population crash brought about by the West Nile Virus a decade ago.

I can't say that I ignore them. They have a raucous manner and one usually knows they are near by, due to their constant chattering and arguing. But they are pretty skittish around humans so they keep their distance. For that reason I was kind of surprised the other day when I walked past a Magpie on the baseball field fence. It just watched me until I was just a few feet away, so I pulled out the camera and snapped a few shots.

Familiarity can breed complacence (I could never hold these beautiful birds in contempt), so it was a nice reminder of what a treasure we have in these birds and what a pleasure it is to be able to observe them.

Why Yes, I am the Center of the Universe: Yellow-billed Magpie on the Tuolumne River

Just a quick single picture tonight. This is a Yellow-billed Magpie (Pica nuttalli), one of California's
very few endemic bird species. Endemics are those species that are found in one place and nowhere else in the world, and this magpie fits the bill very nicely. It is common in California's Great Valley and the Coast Ranges, and is found nowhere else. We almost lost it a decade ago when the West Nile virus decimated the flocks. More than half the population was wiped out. Luckily a few seemed to have had some resistance to the virus and the populations have stabilized somewhat, although not yet to the number that existed prior to 2004 when the virus arrived.

I was thrilled to see a flock of more than a hundred of the Yellow-billed Magpies flying over the campus of CSU Stanislaus a few weeks ago. I've seen as many as two dozen or so at a time on the bluffs above the Tuolumne River in Waterford in recent weeks as well. There are also at least two dozen living on the west campus of Modesto Junior College.

This one that I saw today was obviously saying that it was the center of the Universe by making sure it was framed correctly by the barbed wire.

The Yellow-billed Magpie, One of California's Truly Endemic Species

We have a particularly beautiful bird inhabiting our campus, but unless you live here in California, you don't get to see it except in pictures. It's one of the few true California endemic bird species, the Yellow-billed Magpie (Pica nuttalli). It is related to the Black-billed Magpie that is common across the country, but the two populations are isolated from one another by the Sierra Nevada and they've been separated since the Ice Ages. In general, the Yellow-billed Magpie is better adapted to hot temperatures like those in the Great Valley. Besides the yellow bill, the California birds have yellow around their eyes.

The Yellow-billed Magpies are gregarious, historically gathering in huge flocks and around 2008-2009 it was almost their undoing. The West Nile Virus reached the Great Valley and the magpies were particularly susceptible to infection, which was deadly much more than 90% of the time. Their populations crashed, from more than 200,000 to around 90,000. Even though I was not watching birds carefully at that time, the sudden quiet was disconcerting. It was a real tragedy. Instead of flocks of dozens or hundreds, one would see half a dozen birds at a time.

Luckily, the bird seems to be making something of a comeback. Some of the birds may have developed some immunity to the infection, and my impression is that there are more of them on our West Campus. The flock seems to be about 25 strong. I've been having problems getting close enough to them for photography, but today one landed just outside my classroom and I just happened to have my camera at that moment. I'm hopeful for their future; the world would be a dismal world without them.

Speaking of California Endemics, Here Are Some Yellow-billed Magpies, Found Nowhere Else in the World

The Sierra Nevada is a barrier to more than just humans. Magpies "invaded" the western United States from Asia perhaps 3-4 million years ago, but the populations became isolated as the Sierra rose to higher and higher elevations, separating the Great Valley and Coast Ranges from the rest of the west. Eventually there were two races of magpie, the widespread Black-billed Magpie found across the western states from Canada to Mexico, and the Yellow-billed Magpie (Pica nuttalli), endemic only to California. There is very little mixing of their ranges.

They are entertaining to watch, and are easily seen in my area. I saw these two apparently having a quiet argument on top of a street light ("I'm not speaking to you!") on the west campus of Modesto Junior College (actually, they were just sitting and watching things; I'm not supposed to anthropomorphize animals). Most of the time they are kind of raucous.

They used to be more numerous, at times forming large flocks, but they were decimated, almost catastrophically, by the West Nile Virus. Beginning about 2005, between 50-75% of the population was killed off, until the few resistant ones could begin to reproduce in larger numbers. The birds are making a fairly decent comeback. It would have been a terrible shame to lose them.

Yellow-billed Magpies on the West Campus

One of the few birds that are truly endemic to California, the Yellow-billed Magpies (Pica nuttalli) are an elegant looking species. They have been showing up in larger and larger flocks on our west campus in the last few weeks, and making their presence known in a number of ways. Their squawking has been a nice welcome when I arrive on the campus just after sunrise. One landed this afternoon outside the window of my geology lab.

The Magpies used to flock together in the hundreds, but they were decimated a decade or so ago when the West Nile Virus arrived in California. They were especially vulnerable to the disease, and their flocking nature meant that it was easily passed from bird to bird. The population crashed in just a few years by 50%. Luckily, some birds possessed some resistance to the virus, and their numbers are beginning to recover. It's been obvious to me that the flocks near my house number in the dozens rather than only a dozen, which was the case just two years ago.

California's Endemic: Yellow-billed Magpie on the West Campus, Back from the Brink, Maybe?

California has precious few endemic species of birds. In one sense, this fact seems odd, given the many ecological "islands" in California, isolated environments where evolutionary pressures are the greatest. There are high alpine environments, desert mountain ranges with relict conifer forests, and valleys isolated by high mountain ranges, for instance. I have a feeling that the geology of the state has something to do with it the distribution of birds. There are many environments, but the orientation of the geological provinces is mostly north-south, and routes exist for birds to spread far and wide, crossing political borders into Baja and the Pacific Northwest. There are low exit points from places like the Great Valley and low passes over the margins of the Sierra Nevada. Other vertebrates can't surmount these boundaries the way flying birds can, so the trapped reptiles, amphibians and mammals show a great deal more species variation and endemism (is that a word?).

Endemic species are also vulnerable. Highly specialized species living in a single environment are subject to population disruptions when that environment is altered by the appearance of an invasive species or new disease. We've seen that on a human scale in our state. The indigenous people of the state were almost completely wiped out in the early 1800s by malaria and other diseases, with mortality rates estimated in the range of 90%. Our endemic Yellow-billed Magpies (Pica nuttalli) almost met a similar fate, and only a few years ago.

In 2004, West Nile Virus reached California and the effect on the Yellow-billed Magpie was nothing less than catastrophic. They had almost no resistance to the virus (95% mortality), and their tendency to gather in large flocks made transfer of the virus inevitable. Within two years the population crashed, dropping from an estimated 180,000 birds to 90,000. By 2007, some research suggested that the population had been halved again. Only 5% of the living birds tested displayed any kind of antibody response to the virus. That's an extinction threat.

I have memories of big flocks of the Magpies in our region, and I've not seen anything like them in my travels of the last few years. I was so very pleased to come upon a small flock when I was walking the perimeter of our West Campus on Tuesday. There were a dozen or so birds, and that is probably the largest group I've seen in some time. I saw more of them this evening in my neighborhood as well. I hope it is a good sign. They are gorgeous spectacular birds, and it would be such a shame to lose them.

I can't find any more recent data on their populations. If you know anything, please feel free to contribute to the comments!

Bird of the Day: California's Endemic, the Yellow-billed Magpie

Today's bird is one of my favorites. The Yellow-billed Magpie (Pica nuttalli) is found only in California, mostly in the Great Valley, making it one of the few truly endemic bird species in the state. Some of the others include the Nuttall's Woodpecker (whose range includes a bit of Baja), and the Island Scrub Jay which lives only on Santa Cruz Island in Channel Islands National Park.

The Yellow-billed Magpie closely resembles the Black-billed Magpie that is widely distributed across western North America, except that it has...a yellow bill (and yellow eye-rings). The birds are genetically close, but were isolated from each other by the Sierra Nevada Mountains during the ice ages, perhaps a few hundred thousand years ago.

The birds survived a near-miss a decade ago when the West Nile Virus arrived in California. Nearly half the population was killed off in just two or three years, dropping from an estimated 180,000 individuals to only 90,000 or so. The survivors had some resistance to the virus, so the population has rebounded in recent years. It would have been a real shame to lose these beautiful and unique birds. I've enjoyed watching the flocks in my neighborhood pasture and on the west campus as well.

The last picture is not a great one (I'm working on getting a better one), but the birds in flight remind me of one of the most ancient of bird species, the Archaeopteryx. There is no close relationship, but the long tail feathers make me think of the long boney tail of the Jurassic creature that resembled the transitional species that led from dinosaur to bird (the Archaeopteryx also had teeth, a trait that only appears in bird embryos these days). I guess I'm not the only one to notice, because when I referred to the Wikipedia article on the ancient birds, they also noted the resemblance.

The Magpies on campus and in the pasture are usually pretty suspicious of me (a good trait), so I was pleased when they hung around during my walk earlier this week in the pasture near my house, and again on Tuesday when I walked the West Campus perimeter. There are several dozen individuals in each flock, which is an improvement over the last few years. It had got way too quiet when the virus was destroying the flocks. I'm glad they're back. Look to see them again soon on these pages.