Figure 328. Snowy Owls invaded California only five times during the twentieth century, the latest coming in 1977/1978. One of the largest invasions, during winter 1973/1974, included this bird—probably a first-winter female—photographed on 5 January 1974 at Lake Earl in Del Norte County (1974-007; Ron LeValley).

 

Figure 329. Distribution of 57 Snowy Owls accepted from 1900 through 2003. Except for birds in Butte County in 1916 and Yolo County in 1967, all were found along the coast from Monterey County northward, primarily in Humboldt and Del Norte Counties.

 

Figure 330. A field sketch depicting one of six Snowy Owls present on 16 March 1974 on the south spit of Humboldt Bay, Humboldt County (1974-006; Tim Manolis).

 

 

 

 

 

 

 

SNOWY OWL Bubo scandiacus (Linnaeus, 1758)

Accepted: 57 (83%)	Treated in Appendix H: yes
Not accepted: 12	CBRC review: records from 1900 through present
Not submitted/reviewed: 14	Color image: page H-23

This large owl is a holarctic breeder that is prone to irruptive movements southward. In North America, most birds winter from their arctic breeding grounds south to the northern United States, but during exceptional years individuals have dispersed as far south as Nevada, central Texas, the northern Gulf coast, northern Florida, and Bermuda. In the palearctic, southerly vagrants have reached the Azores, the Mediterranean region, Iran, northern India, and Japan.

According to Grinnell and Miller (1944), “flocks” of Snowy Owls occurred in northwestern California during the winter of 1896/1897, and birds were found south to Alameda, Alameda County (a 2 December specimen; Cohen 1901). Farther south, a bird shot during duck-hunting season near Santa Cruz in Santa Cruz County “probably in 1896 or 1897” (Grinnell and Miller 1944) was rehabilitated and kept as a familiar for some years (Thompson 1901). Three were reportedly collected in Sonoma County around the date of 2 December 1896 (Cohen 1901), but two collected on 8 December 1896 at Eureka in Humboldt County (CMEHS 644, 678) provide the only remaining evidence of this remarkable invasion. The CBRC reviewed and accepted these two extant specimen records (both under CBRC record 1986-318; Bevier 1990), but since they precede the start of the official review period, they do not count in the total number of individuals accepted and are excluded from the table of records. An earlier report of “three or four dozen” in Eureka during October 1895 (Clay 1909) was not documented.

Testifying to this owl’s irruptive habits, all California records since 1900 come from just five winters: 1908/1909 (1), 1916/1917 (21), 1966/1967 (4), 1973/1974 (39), and 1977/1978 (3) (see Grinnell and Miller 1944, Harris and Yocom 1968, Brown 1975, Roberson 1980, Kerlinger et al. 1985, and Harris 1991). In multiple recent winters, Snowy Owls were found in Oregon but not California. See also Appendix H.

Most of California’s Snowy Owl records are clustered on the northern coast (Figure 329). Only eight come from south of Humboldt County, the southernmost involving a bird found on 11 January 1974 at the mouth of the Salinas River in Monterey County. The only inland records refer to an immature male at Gridley, Butte County, 17 November 1916 and a male at Yolo Bypass, Yolo County, 4 January 1967, but the species regularly occurs in the interiors of Oregon and especially Washington. Most California birds have shown the heavy black barring characteristic of first-winter birds and females (see Pyle 1997b). In addition to published photographs listed below, many others have appeared in local newspapers, most of them in 1973/1974.