This blog post is merely to provide a visual illustration, by way of a map, of the expansion of the California Scrub-Jay across Washington, British Columbia, eastern Oregon, Idaho, and even Montana (one record so far). It is intended to complement my more detailed article, “Tracking Expansion of the California Scrub-Jay Into the Pacific Northwest”, in the Washington Ornithological Society (WOS) News, August-September 2021 edition.
As becomes clear in the article, these are not hard lines. The jays are advancing gradually, not in a solid wave. Typically, a single jay will appear well outside the known range (e.g. Spokane). Within a year or two, there will be several. Then they’ll be breeding. Then they will begin expanding further. Meanwhile, a wave of jays will be backfilling the new territory, with densities increasing annually. The lines in this map are as much art as science, but are intended to show the primary region were jays were “regular and expected”. There were always outliers, pioneer dispersers expanding the range. Records beyond the 2020 line are shown as pale blue dots.
The jay’s expansion, when considered in the context of timing and trends in other species, is likely a function of a warming climate combined with suitable food sources. For more discussion of this, see the WOS article linked above.
It will be interesting to see where the 2030 scrub-jay “contour line” will be. I predict they’ll be on Vancouver Island from Victoria to Campbell River, as well as up the Sunshine Coast, up the Okanagan Valley to Kelowna and possibly Kamloops, and east to Idaho, from Coeur d’Alene in the north throughout the Snake River Valley in the south.
After that, they face some formidable hurdles. The biggest obstacles to their expansion further north and east will be habitat with limited food sources (e.g. high mountains). That said, they’ve already shown some ability to travel up mountain valleys and potentially cross the Cascades north of Mount Rainier.
There are a lot of reasons why I’m moving from California to Washington, including family and other personal considerations. But one reason, one big reason, is California’s rapidly changing climate.
It was late February in the Coast Range of northern California when I was wearing shorts and a t-shirt. Dust swirled around my car in the dirt parking lot at Cold Canyon. The car thermometer, warmed by a sun that felt imported from Palm Springs, said 87 degrees; it was actually only 77. A hint of ash, omnipresent since The Fire last summer, remained in the air.
The hillsides were green with the new growth of non-native grass, which was responding to a recent heavy rain. That was deceptive. More than half the rain we’d had in the previous eight months came in that single event. We had six inches of rain in all of 2020. Looking beyond the grass, nearly every tree – blue oaks and gray pines – on the hillsides was dead, burnt black and orange monuments to a previous era. For our local blue oak woodland, that era ended last year and, given that recruitment of saplings is unlikely due to heat, fire, and cattle, it was an era that will never return.
Massive die-offs are eliminating blue oaks from the southern third of their range. Black oaks are marching up the Sierra, displacing Ponderosa pine, which are marching up, displacing firs. Everyone is on the move. Oak woodlands are becoming oak savannahs, oak savannahs are becoming grasslands, grasslands are becoming rocky high deserts. Arizonification is happening quickly, thru heat, drought, and ultimately, thru fire.
Virtually all of the east slopes of the Coast Range between San Francisco Bay and the Trinity Alps has burned in the past ten years. In the Sierra, one can practically predict where the next fire catastrophe will happen, because it hasn’t burned yet (hint: Lake Almanor, Placerville, Arnold).
It was a beautiful day—for April. But February has become April, April has become May, and June, July, August, September, and even October and November have become unrecognizable. Every year more heat records are broken. Hottest summer, hottest month, most days over 100, most days over 90. The list goes on, each year breaking the records set the previous year. Weather data is normally highly variable; now it is a straight line—warmer and warmer. And smokier.
My cape honeysuckle and bougainvillea, both planted with a degree of optimism outside their recommended zone, used to die back so badly in the winter that each spring I was tempted to declare them dead and pull them out. Now they bloom year-round, looking like they’re in a courtyard at a hotel in the tropics. We haven’t had a real freeze in seven winters.
The songs of lesser goldfinches on my street are a depressing warning. I can’t take two steps outside without seeing or hearing a bird that reminds me that our climate has seriously changed. Western tanagers, house wrens, and turkey vultures are regular in winter now. The lesser goldfinches have come out of the arid hills and are quickly becoming one of the most ubiquitous nesting birds in Davis. (I know this definitively because one included an imitation of a canyon wren in its song.) What’s more, at least four Say’s phoebes, essentially a high desert species, are scouting for nests in town now. A fifth arrived on my block last week, singing as if on territory. They’ve been doing this for a few years and their numbers are growing.
I’m leaving. I’ve lived in California fifty-five years but it’s no longer the state I grew up in.
We’re headed to the Olympic Peninsula in Washington. We are fortunate to be able to do so.
I feel like a frog in a boiling pot. I’m getting out. I’m saying goodbye to California, but I feel it has left all of us without saying goodbye to anyone.
I do believe that Homo sapiens may ultimately win the climate battle and bring atmospheric CO2 back down to 300 ppm or something. But that’s a hundred years off. And there’s no guarantee we can stop the tide of Greenland and Antarctic ice melt to prevent sea level rise. In the meantime, in the next 50 to 100 years, it’s going to get a lot warmer. And we may ultimately lose New York City, Singapore, Mumbai, and every other low-lying coastal city. My new home is fifty feet above sea level. Well, probably forty-nine and a half now.
As the climate warms, different thresholds are crossed for different species at different times. For the Lesser Goldfinch, that time seems to be now—both in the core and northern edges of its range, where the species is increasing, and in some parts of the southern arid regions, where it is decreasing.
As I prepare to migrate myself from Davis, California to Port Townsend, Washington, I’m serenaded by Lesser Goldfinches every time I step outside. This is a new thing, a warning of coming heat and smoke brought by a beautiful voice. A more open and arid country version of the American Goldfinch, until five or ten years ago, Lesser Goldfinches were sparse breeders in Davis. I would get a few of them mixed with Americans at my feeder in winter, but I’d have to go west to the more arid edges of the Sacramento Valley, or up into the hot dry foothills, to find them in the breeding season.
They arrived in my neighborhood as nesters about five years ago. This year, 2021, they seem to be the most ubiquitous singing bird, setting up terrorities throughout the town. Friends in Sacramento have reported the same. This comes after several years of record heat and lack of rain (only 6″ in all of 2020).
Here’s what the eBird data says. For comparison, Northern Mockingbird, one of the most common birds in town, is reported from about 20 eBird locations in Davis each June (ranging from 16 in 2015 and 14 in 2016 to 18-22 in the more recent years as eBird users and reports increased). Using mockingbird as a metric for Davis, it’d be fair to say that 20 sites represents close to 100% presence throughout the town, and that number was probably 25% lower (i.e. 15 sites) in 2015. Lesser Goldfinches have increased from reports from four sites in June of 2015 (representing about 20% of the town) to 17 sites in June of 2020 (representing 85% of the town). It feels like it will be 100% this year.
They are not the only arid-country species increasing in Davis as a breeder. Nesting Say’s Phoebes have expanded up from the south, with multiple pairs in Woodland each year (and it’s looking like Davis this year as well).
As with so many less-migratory species, Lesser Goldfinches are expanding north into the Pacific Northwest and beyond. Their colonization of the Columbia River Valley began in the 1950s, with the first state of Washington record in 1951; they are now established around Portland, The Dalles, and in the vicinity of Clarkston on the Idaho border. They remain rare elsewhere, but increases in records have been dramatic in recent years. In the northern Puget Trough region (Chehalis north thru Puget Sound to Canada), June records have increased from 1 in 2015 and 2016 to 10 in 2020 (as reported on eBird). While they have clearly gained a toe-hold in Olympia and Puyallup in the South Sound region, in 2020 they made appearances in Victoria and Vancouver, Canada (not shown in the data because these records were in May, not June).
This is a pattern seen in other resident and less-migratory species. Many of those that were already growing before detectable climate change (around 1985) have expanded noticeably since then. Anna’s Hummingbird is the most dramatic example.
Further east, Lesser Goldfinches are moving due north from Yakima and Kennewick into the Okanagan Valley. June records in this region have increased from zero in 2015 to eight in 2020.
In the Mojave Desert, Lesser Goldfinches have declined. Iknayan and Beissinger (2018) reported them from only 43% of 61 study sites, compared to 68% historically. This is part of a massive avian community collapse in the Mojave Desert, as extreme aridity is pushing many species beyond their limits.
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.
CLICK TO ENLARGE.
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.