Figure 412. The Ovenbird is a regularly occurring spring and fall vagrant through much of California. This one was photographed on 11 October 1998 at Galileo Hill, Kern County (Larry Sansone).

 

 

 

 

 

 

 

OVENBIRD Seiurus aurocapilla (Linnaeus, 1766)

Accepted: 3 (100%)	Treated in Appendix H: no
Not accepted: 0	CBRC review: 1972 records1
Not submitted/reviewed: NA	Color image: none

The northern limit of this warbler’s primary breeding range extends from southeastern Yukon and the southern Northwest Territories east to Newfoundland. The southern limit stretches from eastern Oklahoma to South Carolina. The species also breeds locally and irregularly across the central Great Plains and along the front range of the Rocky Mts. as far south as central Colorado. The wintering grounds extend from Sinaloa, southern Texas, and coastal North Carolina south through Middle America and the West Indies to Panama and northern Venezuela. Wintering birds occur casually south to Colombia and Ecuador, north to the central and northern United States, and in 2005/2006 one spent the winter in southern coastal Washington (NAB 60:278). Migrants are encountered rarely but regularly through much of the West. Peripheral records come from Alaska, Isla Guadalupe, Clipperton Atoll, Greenland, Iceland, the British Isles, and Norway.

California’s first Ovenbird was a first-spring male collected on 29 May 1911 on Southeast Farallon Island (Dawson 1911, CAS 18078). Roughly 900 records have since accrued, the great majority of them spring and fall migrants in the southern two-thirds of the state (for example, Harris 2006 reported a modest total of 34 records from northwestern California). As analyzed below, spring and summer vagrants (5 April–21 July, peaking mid May to early June) outnumber those from fall and early winter (16 August–26 December, peaking in September/October). The following records involve birds that may have attempted to oversummer: Kolb Creek, San Diego County 7 July 1998 (Unitt 2004); a male banded at the mouth of the Big Sur River, Monterey County, 16–25 June 2000 (Roberson 2002); a singing male near Santa Barbara, Santa Barbara County, 11–24 June 2001 (fide D. M. Compton); lower Lee Vining Creek, Mono County, 12 July 2004 (NAB 58:597); and a singing male at Palomar Mtn. State Park, San Diego County, 19 June 2004 (NAB 58:602, fide P. Unitt) and 18 June–9 July 2005 (NAB 59:656). At least 14 records involve birds that possibly or definitely overwintered (5 November–9 April), including one from the far north: Eureka, Humboldt County, 18 December 1985–12 January 1986 (Harris 2006).

The balance between spring and fall records in California varies by region. More than a third of the state’s Ovenbirds have been found on Southeast Farallon Island, where from 1968 to 1999 spring occurrences outnumbered those in fall by 200 to 137, or about 1.5:1 (Richardson et al. 2003). The ratio for the Channel Islands is 24 spring to 17 fall, or about 1.4:1 (P. W. Collins in litt.). A third focal area for migrating Ovenbirds in California is eastern Kern County, where the recent average of five or six records per spring greatly exceeds the recent fall average, which is closer to one (M. T. Heindel unpubl. data, May 2000). Farther south, in the Salton Sink, Patten et al. (2003) reported only three spring records and one in fall. Roberson (2002) reported ten spring and 11 fall records in Monterey County, and, proceeding southward along the mainland coast, the balance reported in the literature tips increasingly toward fall vagrancy. In San Diego, Unitt (2004) reported an average of one Ovenbird every other spring and two per fall. The Baja California Peninsula claims only three in spring versus 25 in fall (R. A. Erickson unpubl. data). The striking concordance in Ovenbird data from Southeast Farallon Island and that from the Channel Islands suggests that the predominance of fall records along the southern coast (and particularly on the Baja California Peninsula) largely reflects the greater level of effort that goes into hunting vagrants during fall vs. spring, although such a bias could be offset to some degree by increased Ovenbird detectability in spring.

¹On the review list 1972–1973