Written by: M. Green
Reviewed by: L. Mewaldt
Edited by: R. Duke, S. Granholm

DISTRIBUTION, ABUNDANCE, AND SEASONALITY

     A common migrant and uncommon summer resident of California.  A rare, but probably
regular, winter resident in southern California (Garrett and Dunn 1981).  A common breeder in
Oregon and Washington, and breeding in the Trinity Mts. of Trinity and Humboldt cos. has
been confirmed in recent years (McCaskie et al. 1979, 1988).  Many postbreeders migrate
south through the Cascade Range and Sierra Nevada in summer, although spring migration
mostly is through the lowlands and foothills (Grinnell and Miller 1944).  Found in a wide variety
of habitats that provide nectar-producing flowers; uses valley foothill hardwood, valley foothill
hardwood-conifer, riparian, and various chaparral habitats in both northward and southward
migration; montane riparian, aspen, and high mountain meadows (to tree-line and above)
used in southward migration.  More common in the southern deserts in southward than in
northward migration.  On the Channel Islands, a rare spring migrant (Garrett and Dunn 1981).
On the Farallon Islands, very rare in spring and uncommon in fall (DeSante and Ainley 1980).

SPECIFIC HABITAT REQUIREMENTS

   Feeding:    Takes nectar from many species of flowering plants; also eats insects, spiders
and tree sap.  Hovers while taking nectar and insects, which it gleans from foliage and
flowers; also hawks insects from air.

   Cover:    Trees and shrubs in many habitats provide cover, including lowland riparian, open
woodlands, scrub, and chaparral, also mountain meadows extending to and above treeline
(Grinnell and Miller 1944).

   Reproduction:    Breeding areas north of California in coniferous forests (Johnsgard 1983);
nest variously placed in berry tangles, shrubs, and conifers.  Nest is an open cup, usually on
a sloping branch near ground (Harrison 1978).  Probably uses similar sites in northwestern
California.  May rebuild on old nest.

   Water:    Drinks by hovering over water, or by sitting in shallow water, and dipping bill (Bent
1940).  Nectar also a major water source.

   Pattern:    Uses riparian areas, open woodlands, chaparral, mountain meadows, and other
habitats rich in nectar-producing flowers, including gardens and orchards.

SPECIES LIFE HISTORY

   Activity Patterns:    Yearlong, diurnal activity.

   Seasonal Movements/Migration:    Arrives in February and migrates north through lowlands
and foothills until mid-April (south) and early May (north); a few remain in the state.
Postbreeder males begin to migrate back through California in late June and early July.  This
early appearance of males in the Sierra Nevada has led some observers to suspect breeding.
Fall migration also takes this species into desert areas.  Most individuals are gone by
mid-September, but a few regularly overwinter, particularly in southern California.

   Home Range:    No data on home range found.  In British Columbia, Horvath (1964)
recorded 7-105 nests per 40 ha (100 ac) in various vegetation types.

   Territory:    Armitage (1955) reported 5 feeding territories of migrants varying from 3.3-37 m²
(36-400 ft²).

   Reproduction:    Nesting recently confirmed in northwestern mt. ranges.  In Oregon, the
breeding season extends from late April through July.  Perhaps less promiscuous than other
North American hummingbirds; males have been observed incubating (Johnsgard 1983).
Female sometimes nests close to others in favorable areas.  Usually 2 eggs laid; occasionally
1 or 3.  No reports of double-brooding found.  Incubation period unknown, but probably close
to other Selasphorus (16-22 days for Allen's hummingbird).  Altricial young tended by female
until fledging at 22 days.  Female performs most nesting duties.

   Niche:    Merlins sometimes prey on this species (Bent 1940).  Owls, other hawks, and
weasels are suspected predators.  Greatest danger probably unseasonable cold that kill
nectar sources and insects.  Hummingbirds are important pollinators of specially adapted
plants.

REFERENCES

Armitage, K. B.  1955.  Territorial behavior in fall migrant rufous hummingbirds.  Condor
     57:239-240.
Bent, A. C.  1940.  Life histories of North American cuckoos, goatsuckers, hummingbirds,
     and their allies.  U.S. Natl. Mus. Bull. 176.  506pp.
DeSante, D. F., and D. G. Ainley.  1980.  The avifauna of the South Farallon Islands,
     California.  Studies in Avian Biol. No. 4. Cooper Ornithol. Soc., Lawrence, KA.  104pp.
Ehrlich, P. R., D. S. Dobkin, and D. Wheye.  1988.  The birder's handbook.  Simon and
     Schuster, New York.  785pp.
Garrett, K., and J. Dunn.  1981.  Birds of southern California.  Los Angeles Audubon Soc.
     408pp.
Grinnell, J., and A. H. Miller.  1944.  The distribution of the birds of California.  Pac. Coast
     Avifauna No. 27.  608pp.
Harrison, C.  1978.  A field guide to the nests, eggs and nestlings of north American birds.  W.
     Collins Sons and Co., Cleveland, OH.  416pp.
Horvath, O.  1964.  Seasonal differences in rufous hummingbird nest height and their relation
     to nest climate.  Ecology  45:235-241.
Johnsgard, P. A.  1983.  The hummingbirds of North America.  Smithsonian Inst. Press,
     Washington DC.  303pp.
McCaskie, G., P. De Benedictis, R. Erickson, and J. Morlan.  1979.  Birds of northern
     California, an annotated field list.  2nd ed. Golden Gate Audubon Soc., Berkeley.  84pp.
McCaskie, G., P. De Benedictis, R. Erickson, and J. Morlan.  1988.  Birds of northern
     California, an annotated field list.  2nd ed. Golden Gate Audubon Soc., Berkeley.
     Reprinted with suppl.  108pp.
 
Compiled from information from California Department of Fish and Game - California Interagency Wildlife Task Group