2023 has been an irruption year for Clark’s Nutcracker, Pinyon Jay, and Pygmy Nuthatch. All three inhabit western pine forests and have been appearing at lower elevations and out of range. Clark’s Nutcracker depends on large-seeded pines such as whitebark (Pinus albicaulis) and pinyons, and Pygmy Nuthatch inhabits long-needled pine forest (including Pinus ponderosa), while Pinyon Jays are found in both large-seeded and long-needled pine habitats. Large-seeded and long-needled pines are presumably producing poor seed crops this year, sending Clark’s Nutcrackers, Pinyon Jays, and Pygmy Nuthatches further afield in search of food.

Clark’s Nutcrackers are legendary for their ability to cache thousands of seeds every fall. They feed on whitebark and other large-seeded pines, which in turn rely on nutcrackers for seed dispersal. Clark’s Nutcracker is usually found at elevations of 3,000−12,000 ft. (900−3700 m) and may move to nearby lower elevations as their preferred seeds ripen, or further into the lowlands and even well out of range when food is scarce. Irruptions occur when a successful breeding season precedes a crop failure, resulting in a high population of juveniles and a low food supply. About a dozen major irruptions of Clark’s Nutcracker have taken place in the last century. The most recent was in 2018−2019, and previous irruptions were documented in 1919−20, 1933−34, 1950−51, 1955, 1961−1962, 1968−69, 1972−73, 1973−74, 1986−87, 1996−97, and 2004−05. During irruptions, birds that descend into the lowlands typically remain there through the subsequent breeding season.

Unusual reports of Clark’s Nutcracker were widespread from British Columbia to southern California on the west coast, as well as east to Texas, Nebraska, Minnesota, and Wisconsin. In Cascadia, there was an influx of nutcrackers into Clallam Co, Washington, and a few turned up on Vancouver Island, British Columbia. A flock of seven was unexpected in Tillamook Co, Oregon. Further south, the species appeared in coastal California (Monterey, San Francisco, San Mateo, and Santa Barbara Cos), as well as in lowland desert in San Bernardino Co and the Laguna Mountains in San Diego Co. In Colorado, nutcrackers were found away from their usual subalpine habitat in Boulder, Larimer, Douglas, and El Paso Cos. Wyoming birders reported lowland nutcrackers in Carbon, Fremont, Sweetwater, and Laramie Cos. Idaho hosted the species at relatively low elevation in Jefferson and Madison Cos. Elsewhere, unusual reports came from Nevada’s Desert NWR, Santa Cruz and Pima Cos in Arizona; Santa Fe Co, New Mexico; and Box Elder and Tooele Cos, Utah.

On the eastern frontier of the species’s range, there were Clark’s Nutcrackers in the Guadalupe Mountains in Culberson Co, Texas, as well as Gosper Co, Nebraska. The latter bird occurred not far from the Platte River some 350 miles (560 km) downstream from the species’s usual range. In the Western Great Lakes region, a nutcracker video recorded in Washington Co, Minnesota represented a first county record, and about the 25th for the state. Further east, Wisconsin’s seventh turned up in Dane Co. Unsurprisingly, all of Wisconsin’s previous records also occurred during irruption years (1961, 1964, 1973, and 2018).

Pinyon Jay irruptions usually co-occur with nutcracker irruptions, and fall 2023 is no exception. “Piñoneros” harvest and store seeds like Clark’s Nutcracker, but the jays’ diet is more varied than that of nutcrackers. Pinyon Jay coevolved with pinyon pine (Pinus cembroides), and their relationship is mutually beneficial: the pine relies on the jay to disperse seeds, and the presence of pine seeds and green cones trigger the physiological changes in the jays necessary for breeding. North of pinyon pine range, the jay occurs in ponderosa pine and mixed habitat. Pinyon Jays are typically nomadic within appropriate habitat, except in breeding season, when they nest wherever the pine seed crop is abundant. This fall, unusual reports came from Idaho in Blaine and Ada Cos, away from the jay’s typical range. Elsewhere, a flock of 10 was unexpected in lowland Los Angeles Co, California. In Colorado, there were multiple reports of the species north of Denver from the I-25/US-287 corridor away from the usual foothill sites, and one in Kit Carson Co was well out of range. Another noteworthy record came from Thurston Co, Washington, where a lone Pinyon Jay visited backyard feeders.

Pygmy Nuthatch is a denizen of old-growth long-needled pine forests, especially ponderosa (P. ponderosa) and Jeffrey pines (P. jeffreyi). This species is highly social, like Pinyon Jay, but typically sedentary with some post-breeding dispersal. Although there have been documented invasions by Pygmy Nuthatch, most recently in 2017, of the three species discussed here, it may be the least likely to wander. True to form, many of the out-of-range records pertained to multiple birds. This season, in British Columbia, one at Tatlayoko Lake Bird Observatory was well north of the southern valleys where the species is usually found in the province, and on Vancouver Island, another came to feeders in Sidney. There were remarkable lower-elevation movements into coastal Washington (Clallam, King, and Jefferson Cos) and low-lying and coastal areas of Oregon (Clatsop, Columbia, Multnomah, Lincoln, Benton, Lane, and Tillamook Cos). In California, Pygmy Nuthatches were found in coastal Humboldt Co, as well as the state’s central valleys (Placer, Fresno, and Kern Cos). Further east, a few found the closest thing to suitable habitat in central Nebraska—in the Halsey section of Nebraska National Forest—well away from the species’s limited range in the state’s panhandle. Finally, a Pygmy Nuthatch at feeders in Regina, Saskatchewan was extraordinary.

Other western mountain-dwelling birds are also on the move this fall—Gray-crowned Rosy-Finch comes to mind. It will be interesting to see what the rest of the fall and the winter have in store.

Recommended citation: Davis, Amy. 2023. Clark’s Nutcracker, Pinyon Jay, and Pygmy Nuthatch Irruption 2023. North American Birds.

Sources:

Newton, Ian. The Migration Ecology of Birds. 2007.
https://birds.outdoornebraska.gov/clarks-nutcracker/

Tomback, D. F. (2020). “Clark’s Nutcracker (Nucifraga columbiana), version 1.0.” In Birds of the World (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology. https://doi.org/10.2173/bow.clanut.01

Johnson, K. and R. P. Balda (2020). “Pinyon Jay (Gymnorhinus cyanocephalus), version 2.0.” In Birds of the World (P. G. Rodewald and B. K. Keeney, Editors). Cornell Lab of Ornithology. https://doi.org/10.2173/bow.pinjay.02

https://www.americanforests.org/article/the-race-to-save-the-whitebark-pine/

wsobirds.org/images/pdfs/Wisconsin_Rare_Bird_Records_2022.pdf

https://sora.unm.edu/sites/default/files/journals/wilson/v076n01/p0010-p0018.pdf

https://sdplantatlas.org/ge_files/pdf/Clark’s%20Nutcracker.pdf

https://www.birdatlas.bc.ca/accounts/speciesaccount.jsp?lang=en&sp=PYNU

Ted Floyd, personal communication.

Mia McPherson, personal communication.

Michael Retter, personal communication.

Amy Davis is Associate Editor of North American Birds and special issues of Birding, as well as Editor of ABA’s online Field Ornithology series and Regional Compiler for NAB’s Hudson-Delaware region. She supports community science, participates in various breeding bird atlases, and serves on two state records committees. A lover of fishing and pelagic birding, Amy resides in Forked River, New Jersey.