By Terry Hunefeld
It all began at the 22 December 2007 Oceanside Christmas Bird Count when 6 Allen's or Rufous/Allen's Hummingbirds were recorded - all or most of which were probably the Allen's subspecies Selasphorus sasin sedentarius - in an area where more than one individual had never been recorded on a Christmas Bird Count.
2008 CBC: The 2007 record was shattered on 26 Dec 2008 when 26 Allen's or selasporhous sp (Rufous/Allen's Hummingbirds) were recorded.
2009 CBC: An astonishing 88 Allen's and/or selasporhous sp were recorded on Dec 26, testament to the speed at which this species is colonizing north county San Diego.
S. s. sedentarius has been a long-time permanent resident of the Channel Islands. It made the leap to the mainland and colonized the Palos Verdes Peninsula of Los Angeles County in the 1960s and 1970s. In recent years, its range has expanded inland through much of the coastal slope of Los Angeles County, and south into Orange County (Howell, 2003).
Allen's Hummingbird was confirmed nesting in San Diego County for the first time in 2001 when 3 were found at San Onofre State Beach (20 Jan 2001). Since then, more have been seen each winter. (Unitt, 2004).
Allen's Hummingbirds were found in Riverside on 5 Jan 2007 and near El Centro on Feb-Mar 2007 both areas where few had been previously seen. Another reported in Ocean Beach (26 Dec 2006) was S. s. sedentarius providing additional evidence that this subspecies is expanding its range southward into San Diego (McCaskie & Garret, 2007).
Allen's Hummingbird has colonized as far east in northern San Diego as Fallbrook, where it is now resident (Phil Unitt, pers. comm. 25 Jan 2008).
Neither Phil Unitt nor Guy McCaskie are surprised at the rate at which Allen's are moving into northern San Diego County given the speed at which they colonized Los Angeles and Orange Counties. McCaskie is certain that 99% of all Rufous/Allen's Hummingbirds reported in North County on the 2007-2009 Christmas bird counts are Allen's, at least until proven otherwise with photographic documentation.
Allen's Hummingbirds are particularly attracted to Cape Honeysuckle, popular with landscape architects and planted with increasing frequency in residential areas. Large, mature flowering shrubs have become "hummingbird- magnets" covering entire hillsides and are ripe for more discoveries of more wintering Allen's next season.
A distribution map of the 22 Dec 2007 Christmas bird count sightings is available at the following link. A map with icons representing the locations of sightings will be displayed. Clicking on any icon brings up a text box with more details of each sighting. Zooming in or out provides more or less detail.
After January first it's likely that the northward migration from Western Mexico of the nominate race "S. s. sasin" will have begun, obscuring further findings of wintering sedentarius until the next season.
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Howell, S. N. G., 2003. Hummingbirds of North America. Princeton
University Press. Princeton and Oxford.
McCaskie, G., and Garrett, K. 2007. Southern California Records Dec
2006 Mar 2007. North American Birds 61:328.
Unitt, P. 2004. San Diego County Bird Atlas. San Diego Natural
History Museum. San Diego, California.
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