Since fall is down time for atlas field work, there aren't a lot of atlas-generated discoveries to report. Still . . .
Peter Ginsburg found a pair of Clark's Grebes on a nest at O'Neill Lake, square E6, in August, a new breeding site for this species. Western Grebes were summering on the lake as well.
With only occasional breeding-season reports and circumstantial evidence of breeding by the American Bittern in San Diego County, any summer observation of this species is of interest. Robert Sanger saw one on 28 June along the San Diego River in square L17, Mt. Gower, though there was no marsh adequate for the species' nesting. Another seen by Peter Ginsburg at O'Neill Lake on 27 August could have been a fall migrant.
Little is known of the nesting of the White-headed Woodpecker in San Diego County, so David Rawlins' observation of a pair feeding young in square D15, Palomar Observatory, on 25 May is notable.
Breeding Vermilion Flycatchers retain only a tenuous hold on San Diego County. Mel Gabel found the only nest on 2 May at the De Anza Country Club in square F24, Borrego Springs N. And the only other report was of one at a traditional location, Butterfield Ranch in square M23, on 22 July by Mary Beth Stowe.
Though gradually expanding its range, the Bronzed Cowbird is still very rare in San Diego County. Two records this year: a pair seen by Frank Unmack on 15 April in U27, Boundary Creek, and one trapped in the cowbird trap at Horse Camp in the Anza-Borrego Desert (square E24, Borrego Valley N) on 28 April. The latter supplied only the second specimen of the Bronzed Cowbird for the county.
WRENDERINGS isn't the place for listing all the rare migrants seen in the county, but a column on notable discoveries has to include a few highlights:
7 Fork-tailed Storm-Petrels seen from shore at La Jolla (P7) on 7 October by Stan Walens
A Sooty Tern seen from Silver Strand State Beach (T9) on 2 September by Brian Foster (scouting for another nesting attempt?!)
A Ruddy Ground Dove seen in the Tijuana R. Valley (V10) on 18 October by Guy McCaskie
A male Broad-billed Hummingbird found in the Tijuana R. Valley (V10) on 5 October by Phil Unitt and Jack Schlotte
Yellow-green Vireos found on Point Loma (S7) on 28 September by Doug Aguillard and at San Elijo Lagoon (M7) on 8 October by Mike Overton
A Prothonotary Warbler found on Point Loma on 30 September by Peter Ginsburg
A Kentucky Warbler struck a window, killing itself, at the home of Don Grine in the southwestern corner of square L8, Rancho Santa Fe, on 2 October. There have been 11 previous records of the Kentucky Warbler in San Diego County, but this is the first specimen.