The decline of Mountain Plovers in two graphs

I live in Yolo County, California, near Sacramento, where Mountain Plovers used to be an annual winter specialty. Searching for “dirt clods with legs”, we used to be able to find dozens of these unique shorebirds, sometimes over a hundred.

Those days are over. They are now “irregular”, meaning we don’t find them every year. We’ve struck out five of the last eleven years. Before that, we averaged a high count of 72 individuals. The first graph, built from records in the Yolo Audubon Society newsletter, emails to the Central Valley Birds listserv, and eBird, shows the high count each winter in Yolo County.



This second graph backs out a bit in space and time, looking at all Mountain Plovers worldwide, starting in 1980. They are a bird of the steppe, breeding mostly on the Great Plains between the Rockies and the flat lands, between the Canadian and Mexican borders. They winter in open country in a vast arc west and south of there, mostly in California, Arizona, New Mexico, and Texas.

MOPL cbc

All the Christmas Bird Counts nationwide, plus Mexico, averaged 728 birds per count thru 1994, but have never hit that mark since. Fewer than 200 individuals have been enumerated six of the last ten years. Adjusted for party hours, the graph basically looks the same.

Hell in Paradise: Why the Camp Fire was the largest climate-induced mass mortality event in modern history

fires Paradise

The Camp Fire was started by downed power lines, spread from a forest, and then became a structure-to-structure urban fire in which houses burned but many trees did not.

I grew up in southern California on the edge of the San Fernando Valley. Fires, usually fueled by Santa Ana winds on dry grasses in the hills, were a fact of life. I evacuated. I ran the pump to squirt water from the pool onto the roof. I helped neighbors on the edge of the hills water their roofs. Back in those days, in the 1970s, fires over 100,000 acres (~150 square miles) were rare. The worst fires destroyed 200 to 300 homes. Rarely, someone died. That was then.

fires infographic

Infographic prepared in 2013, before most of the recent mega-fires.

Twelve years ago, four researchers examined a comprehensive database of all large wildfires in western United States forests since 1970. They detected a signal and concluded that “large wildlife activity increased suddenly and markedly in the mid-1980s.” Looking at weather data and land-use history, they concluded the driving factor was “increased spring and summer temperatures and an earlier spring snowmelt”. Forest management, on the other hand, had “relatively little effect”. Published in the journal Science in 2006, they had found the “force multiplier” that climate change brings to the West. We all knew that forests had been mismanaged for nearly a century, and that too many homes and towns had been built up against wildlands.  But now there was a new factor driving fires—longer hotter drier summers. If you’re looking for numbers, the data show that fires really ramped up in 1987.  The so-called “force multiplier” of climate change was big—about 3 or 4. That is, wildfire frequency was triple in dry years when compared to moderate years, and quadruple that in wet years. Ominously, they noted the effect was non-linear, meaning that, in warmer years, fires really increased. Thus, the multiplier was not just a constant number—it increased with temperature and lack of rain. The Berkeley Tunnel fire, which was exceptional because it killed 24 people trying to evacuate and was the first fire in California history to burn over a thousand homes (it actually burned over 2,000 homes), occurred in 1991.

In the twelve years since the Science article, mega-fires, in terms of acres burned, structures destroyed, and people killed, have gone off the charts—literally. When it comes to fires that burn more than 200,000 acres (~300 square miles), destroy more than a thousand homes, and kill dozens, if not hundreds of people, climate change is not really a “force multiplier”, it’s an on-off switch. Such fires were very rare or non-existent before the year 2000. Now, they appear to be annual.

CA fires 2b

We’ve crossed a threshold, tripped a wire.  In 2017, after the astounding loss of 6,000 homes in Santa Rosa, we hoped that was an outlier, a blip in the data. A few months later, in December, when fires were previously unheard of, the Thomas Fire became the largest in state history. Barely six months later, the Carr Fire made Redding “the new Santa Rosa”. After that fire I posted a chart showing that 16 of the state’s largest 20 fires had all occurred in the past 20 years. We had a reached a “new abnormal”. Then, a few months after that, in November, when by all historical standards the fire season should be over, the Camp Fire literally wiped out the entire town of Paradise, population 26,000. Hospitals, high schools, stores, and houses, all gone. The death toll is without historical precedent. While that was burning, the Woolsey Fire became the largest and most destructive fire in the history of the Los Angeles area. At the present rate, next year the Paradise inferno will be surpassed by some hell unimaginable.

CA fires 2a

When I say the Camp Fire is the largest climate-induced mass mortality event in modern history, I’m not counting hurricanes. Hurricanes, even large hurricanes, have always occurred and always will. A Category 5 hurricane striking a major city is an inevitability. Yes, climate change has made hurricanes larger and more numerous, thus increasing the risk, but nothing like the change we’ve seen with fires in the West. Thus, attributing any one hurricane to climate change is like attributing a single specific cancer case to an environmental contaminant causing a cluster of cases.

CA fires 2c

When I say the Camp Fire was caused by climate change, I’m not saying that future destructive fires are inevitable. The fires will come, but we can do things to mitigate the


Graphic from

destructive aspects. A full post-mortem on the Camp Fire and other recent mega-fires is of course required. Such analysis should look beyond the political rhetoric of Trump, exclusively blaming management practices in national forests. Most of these fires in these graphs, spreading across dry grass and oak woodland, had nothing to do with forests. Furthermore, in the face of massive tree death from drought, simply removing dead trees from forests has serious feasibility limitations. To quote a forest fire expert colleague, “Yes, fuels reduction is needed same as 30 years ago, but the mills are all full from the tree mortality supply, much of the fuels are not merchantable, and we are not going to cut our way out of longer fire seasons and deadly MegaFires.”

In the short run, we can’t stop the changing climate, the record low humidity and record high dry vegetation, or the longer summers. We can’t shorten the fire season, now 80 days longer than in 1970s. But we can modify power lines, conduct preventative burns, revise urban fire perimeter requirements, and re-evaluate evacuation routes. Those things won’t turn off the switch we’ve triggered, but they might at least save some homes and lives in the coming years.


The CalFire damage inspection map of Paradise. The latest interactive map can be found here

Why are so many Eurasian Collared-Doves leucistic?

0V2A6850In 2006, I wrote a paper about the spread of the non-native Eurasian Collared-Dove into the Central Valley of California. At that time, there were about 43 records. Now, of course, the species is widespread and common. Quoting from that paper, here’s the backstory of their spread throughout North America:

The Eurasian Collared-Dove was first observed in Florida in the late 1970s. These birds likely originated from an accidental release in the Bahamas in 1974. Since then, their spread has been well documented by Christmas Bird Count and by state bird record committees. By the mid 1990s, the species had been recorded throughout the southeast United States. By 2000, Arizona, Idaho, Oregon, Utah, and Washington had documented records. On the 106th CBC (December 2005 – January 2006), over 30,000 individual birds were reported nationwide, compared to just 560 fifteen years earlier. Their rate of increase has averaged 34% per year.

Today, it seems that in any large aggregation of Eurasian Collared-Doves, there are one or two that are unusually pale, blotched with white and cream. They seem to be about 1% of the population or more, though it’s yet to be studied. These birds bare a strong resemblance to African Collared-Doves, which is generally this pale.  However, based on the dark outer web of the outermost tail feather (see below), as well as size and vocalizations, these birds are clearly leucistic Eurasian Collared-Doves.


EUCD diagram

All of the photos on this page involve the same two darker doves and one pale dove. Above, the tail patterns of the dark dove (left) and pale dove (right) both suggest Eurasian Collared-Dove.  Woodland, California, October 2018.

0V2A6835Many birders suspect this is due to the Founder Effect, a phenomenon that occurs when a small population colonizes a large area. Eventually, all of the birds (or other animal species) are descended from few individuals. In this context, certain recessive traits that were once rare may become more common.

See the Wikipedia account of the Founder Effect for examples of this in human populations.


Here, one of the darker doves is mating with the pale dove.


The international climate report in three diagrams: The world at a crossroads

On October 6, 2018, the Intergovernmental Panel on Climate Change (IPCC) issued its Special Report on Global Warming of 1.5 °C (known at “SR15”), looking at the benefits of keeping global warming under 1.5 °C, as compared to 2.0 °C, and the potential pathways to get there. The report was commissioned after the Paris Agreement of 2015, which subjected nearly every nation in the world to voluntary goals for reducing greenhouse gas emissions. We are already at 1.0 °C and climbing, so this is a late-in-the-game analysis.

The results, based on the latest science, are sobering. While past IPCC reports were known for being rather conservative, largely due to political pressure, this one is more direct, practically screaming for a radical reduction in fossil fuel use (which must fall to near zero by 2060 even with a technological breakthrough in carbon sequestration). When it was approved, participating scientists cried tears of joy that their report, dire as it is, was allowed to be published as it was.

The full report, a little over 1,000 pages, is available in chapters here.  It provides important details regarding the effects of climate change from region to region.

A 34-page summary for policy-makers is available here.

But even that summary is full of technical jargon that most politicians and members of the public would find cumbersome. Here I’ve taken some of the most important diagrams from the summary and modified and annotated them.  Here is the report in three diagrams:








How to stop birds from flying into your windows

Window strikes kill hundreds of millions of birds each year. It’s a terrible feeling when you’ve set up a feeder just so you can watch the birds and it becomes a death trap, luring birds into food, only to be followed by a sharp “thunk” against your window, resulting in a stunned and sometimes dead bird.


My falcon decals look great from the inside, but they are nearly impossible to see from the outside. Since they don’t move, they don’t attract attention. They did little to stop window strikes.

Here I present one solution from my backyard. The key is something in front of the window that allows the birds to see it and realize what it is. Moving objects, like ribbons that move in the wind, work best. Still objects, like falcon decals and plastic owls, work poorly. Additionally, the maximum range of effect of a window marker is only about 18 inches. I’ve had birds hit my window within 18 inches of the falcon decoy.

Here is my solution, which is quite effective. Tack a shiny ribbon to the top middle of each window, hanging down most of the length of the window.  I had a name brand mylar ribbon designed for the purpose (probably a Father’s Day gift), but any shiny ribbon will probably work. There are other similar brands on Amazon. The key is that it moves in the slightest breeze, reflecting off and revealing the window behind it.


This 8-second video illustrates how the slightest wind moves the ribbons, making the windows apparent. Note the falcon decals are still there, just hard to see.

Finally, here’s a view from inside the house with the ribbons in place. From the inside, they are much less noticeable than the decals. From the outside, it’s a different story.


Another thing to experiment with is the placement of your feeders. I once hung a thistle feeder very near the windows. This resulted in several goldfinch deaths, as they tend to flush from the feeder in a fast direct flight. I moved the feeder back ten feet, which made a huge difference, apparently giving them time to see their options while flushing.

The 2018 flight of the Buff-breasted Sandpipers: Data from the West Coast

Buff-breasted Sandpipers breed on the Arctic tundra from western Alaska, across northern Canada, to Baffin Island. They winter eight thousand miles to the south, on the grasslands of the River Plate Basin in Argentina, Uruguay, and Paraguay. Their primary migration corridor is east of the Rockies, through the central United States. A secondary route is along the East Coast. They are always rare in fall migration along the West Coast, with four to fourteen individuals counted each fall between 2014 and 2017. In spring, they are almost unheard of (there is one record in eBird from Arcata, California in May, 1980).

Fall migration in 2018 was exceptional on the West Coast, with sixty-five individuals reported, five to ten times the norm. The figure below summarizes eBird data from the past five years in southern British Columbia, Washington, Oregon, and California.



A few interesting points:

  • While fall migration generally spans from mid-August thru late September, the timing of records within that period are not strongly correlated with latitude.  That is, it does not appear that birds are moving from north to south through the period. Each season’s latest records, from mid or late September, may come from British Columbia or Washington as easily as from southern California. That said, in 2018, the latest records are indeed from southern California. Moreover, the very few October records over the years (not included in the graph) are from southern California.
  • They are most reliable in the Pacific Northwest, only reaching California in years of relative abundance, such as 2018. The only location with records from every year is Salmon Arm Bay of Shuswap Lake, in the interior of British Columbia. Other sites, with records in all but one year, are Boundary Bay, British Columbia, and the south coast of Washington (e.g. Ocean Shores, Gray’s Harbor vicinity).
  • The vast majority of records are of single individuals. The only time more than four birds were documented together during these years was in 2018, with five birds at once at Sauvie Island, Oregon, and a remarkable thirteen at Boundary Bay.
  • In the years 2014-2017, Buff-breasted Sandpipers first appeared between August 15 and 19. In 2018, they did not appear until August 23, and most were relatively later than birds in previous years.
  • In 2018, there were several records from offshore California: one from the Farallons, two from San Clemente Island, and two birds seen together from a pelagic trip one hundred miles off southern California. These were all relatively early in migration, between August 25 and September 1. In contrast, most 2018 records from the Oregon coast were from the first week of September.



The basics of Fox Sparrow identification

While there are over a dozen subspecies of Fox Sparrows, they fall into four main groups: Sooty, Red, Slate-colored, and Thick-billed. The images and diagrams below illustrate the main differences.

Sooty is the darkest, usually illustrated as dark chocolate in most guides. Even the darkest Sooties, however, show some gray on the face and rusty tones in the wings and tail– especially in bright light. I’ve chosen a photo in sunlight to show how lighting can change a bird from dark brown to bright rust. Regardless, the back is solid brown.


Red is the common form that breeds across the taiga to Nome and Bethel, Alaska, and generally winters in the eastern US.


Slate-colored is the Rocky Mountain version, found throughout much of the mountain West. Note that some consider altivagans, from Alberta, an intergrade swarm between Red and Slate-colored.


Thick-billed is the southern Cascade and Sierra Fox Sparrow, found in the mountains south and west of Slate-colored range.


A key distinguishing feature is back color and pattern.


Less useful due to variation, but still helpful, are tail and bill length.




Most forms of Fox Sparrow winter in the lower 48, with southern California host to nearly all subspecies. This photograph shows the green chaparral along the Angeles Crest Highway where a wide variety of Fox Sparrows can be found.

For a more detailed analysis, including discussion of Sooty subspecies, see my paper:

Hampton, S.  2016.  Status and Identification of Fox Sparrow Subspecies in the Central Valley of California. Central Valley Bird Club Bulletin 19(2-3): 28-63.

The Coming Green Wave

This op-ed in the New York Times boldly declares:

“if just one unorganized voting segment, the 60 million bird-watchers of America, sent a unified political message this fall, you’d have a political block with more than 10 times the membership of the National Rifle Association.”

There are other fun stats, like there are more yoga instructors in the US than there are coal miners. Enjoy. And vote.



Fall Migration in the Central Valley

warblers fall 2018In 2010, after ten years of collecting data on morning “warbler walks” in my local patch, the Central Valley Bird Club Bulletin published my results. You can read the whole paper here:

Hampton, S. 2010. Passerine migration patterns in Davis, Yolo County—2000-2010. Central Valley Bird Club Bulletin 13(3): 45-61.


Bay Area birders are surprised when I tell them Willow Flycatchers and MacGillivray’s Warblers (above) are daily in fall migration in Davis.

It begins with this:
“Although passerine migration may conjure images of Point Reyes for many local birders, the Central Valley, with its north-south orientation, is believed to be the primary migration corridor through California for most species, surpassing the coastline in this regard (Humple and Geupel 2002).”


Here, I’ve re-visualized my results for fall migration in two simple graphs, one for more common species (peaking at 2 to 13 birds per survey), and another for less common migrants (around 1 or less per survey).




A few caveats:

  • A “survey” here is basically a morning walk lasting about 35 minutes.
    This was for my little route in north Davis. For other locations in the Central Valley, even nearby ones, I would expect the numbers and relative abundance to vary a little. For example, I see a lot more flycatchers at Babel Slough and Grasslands Park than are reflected here.
  • Putah Creek near Pedrick Rd, a current favorite of birders, generally has more birds than is shown here because it’s a larger area, birders spend more than 35 minutes when they visit, and the habitat is slightly different. It seems better at holding fall migrants for more days, making their detection more likely.
  • On these new graphs, I’ve left out the rarer birds, species that occur at a rate of less than 0.2 birds/survey (less than 1 out of every 5 surveys).
  • A large portion of the birds in my data are “heard only”.
  • For spring migration and additional details, see the full article linked above.

This last graph provides a cumulative view of all the migrants at once. Peak diversity is in late August. After that, the Yellow Warblers take over. After that, not shown here, the Yellow-rumped Warblers, both Audubon’s and Myrtle, arrive, signalling the end of fall migration.


It would be interesting to compare these relative abundances and timing with more recent eBird data, both in north Davis (where the eBird hotspot for this survey area is “North Davis Farms Subdivision”) as well as other locations in the Central Valley. Have at it. I’m happy to provide my Excel spreadsheets of this data to anyone interested.


California apocalypse again: Large wildfires increasing with climate change


Sunset from the Central Valley, looking toward the Coast Range through the smoke of a million trees.

As I write this, helicopters are passing overhead in a dim gray-brown sky. The sun is a pink orb over the western horizon. It is 97 degrees at 7pm. The people of California sit like frogs in a slowly boiling pot.

Average temperature for July and August, here in Davis, is 93 degrees. But in the past 34 days, it was only below that six times. July 2018 was the hottest month in the history of the state.

Such climate change was predicted, with great accuracy, by both oil companies and government scientists back in the 1980s, and even earlier.  The consequences of this included more extreme weather, more drought, shorter rainy seasons, earlier snow melt, longer fire seasons, and larger fires. All that is coming to pass in such dramatic fashion that new records are set each year.

CA fires1In 1988, scientists were excited– and alarmed– to see the first indications of a warming climate. Now, graphs illustrating climate change need no statistical analysis. They are obvious to a child, ramping steeply up with each passing year.

CA fires2

A conservative talking point seems to be that this dramatic increase in fires is not due to climate change, but to poor forest management. While this has been an issue for over a hundred years, this question was the prime focus of Westerling et al 2006 in Science, where he concluded that longer hotter summers and shorter drier winters were indeed to blame. There were increased fires even in areas without poor management– or any management at all. Where there has been poor forest management, climate warming has acted as a “force multiplier” to make fires even worse. One could only imagine how easy it would be to write that paper now, twelve years later, with plenty of new eye-popping data points.  Thirteen of California’s 20 largest fires have occurred since Westerling sent his paper to the publisher.

Perhaps the best illustration of the combined effect of poor forest management and climate change comes from this 14-minute Ted talk given by Paul Hessburg in 2017.

Using a useful forest diagram, he explains how Native Americans regularly burned underbrush and maintained an open forest/meadow ecosystem that effectively prevented large wildfires. In the late 1800s, with the ethnic cleansing of Native Americans, the advent of cattle that ate the grass, and the US Forest Service suppressing fires and logging the largest trees, our forests changed from a mosaic of tough old trees surrounded by natural fire breaks to a solid crop of young growth. Add drought, heat, and an ignition source, and you see the results above.

CA fires3

The solution, regardless of how much you attribute large fires to climate change or management, is the same. We need to re-create the balance of the past thru the protection of large trees and prescribed burns. We need to create meadows and healthy forests. Some Native communities in northern California are planning to do this.

This all assumes that we get enough rain in winter and cool temps in summer to allow re-growth. Otherwise, the current fires may be transforming California’s mountain habitats into something resembling the mountains of Nevada and Arizona in the span of a decade.