33RD REPORT OF THE CBRC: 2007 RECORDS 
Figure 2. The first Lesser Frigatebird (Fregata a riel) for California and the fourth for 
North America was well documented at Areata, Humboldt County, on 15 July 2007. 
Sullivan et al. (2007) summarized the features distinguishing the Lesser from other 
frigatebirds, many of which are visible in this photo (see text). 
Photo by Brian L. Sullivan 
western Pacific to Korea and Japan, casually to Kamchatka and the northwestern 
Hawaiian Islands. It also breeds sparingly in the south Atlantic and the western Indian 
Oceans (AOU 1998, Brazil 2009). 
Sullivan et al. (2007) analyzed the bird’s identification in detail. In summary, its molt 
pattern suggested the bird was in at least its third cycle, and the pattern of incoming 
plumage (lacking dark mottling on the white underparts; developing a completely 
dark head) identified it as a female. (1) The black partial collar across the lower throat 
was too extensive for a Great Frigatebird; (2) the prominence and whiteness of the 
collar on the hindneck indicated the Lesser rather than the Great; (3) the cinnamon 
on the lower throat suggested a species other than the Magnificent; (4) the black of 
the lower belly extended up through the central portion of the belly and lower breast 
in an inverted V shape, as typical of the female Lesser and Magnificent but not the 
Great, which shows a more evenly U-shaped belly patch; (5) white extended from 
the breast onto the axillaries as a solid patch rather than as pale scalloping as in the 
Magnificent and Great; and (6) the well-developed pink orbital ring indicated the Lesser 
Frigatebird. Other characters, including the pink bill and feet, were also consistent 
with the Lesser. Many of these features can be seen in Figure 2. Sullivan et al. (2007) 
also briefly discussed the elimination of the other two species of frigatebirds, which 
are much less likely to occur in California, the Christmas Frigatebird ( F. andrewsi) 
and the Ascension Frigatebird (F. aquila). 
TRICOLORED HERON Egretta tricolor (55**, 5). Single birds were at Fig Lagoon, 
IMP, 10 Feb-4 Mar 2007 (GMcC; DVB, HDf, MTH; 2007-051), the southeast corner 
of the Salton Sea, IMP, 3 May-5 Sep 2007 (HBK, EM; RFrf, GMcC; 2007-114), the 
San Diego R. mouth, SD, 15 Nov 2007-29 Apr 2008 (MJBf; PEL, GMcC, JPet, 
DSet; 2007-261), and the Tijuana R. estuary, SD, 25 Nov 2007-18 Apr 2008 (SMa; 
PEL; CAM, GMcC, BiM; 2007-275). One was photographed near Woodlake, TUL, 
in Jun 2000, but the specific date is unknown (GLf; 2007-288). 
166 
