Anna's Hummingbird

Calypte anna Lesson

Nest
Location
Nest
Type
Eggs &
Mating System
Dev. &
Parental Care
Primary &
2ndary Diet
..
Foraging
Strategy
F
I: 14-19 DAYS
ALTRICIAL
SHRUB
1.5 feet - 30 feet
F
2
(1-3)
PROMISC
F: 18-23 DAYS
F
INSECTS
HAWKS

BREEDING:

Open woodland, chaparral, gardens. 2, possibly 3 broods

DISPLAYS:

Male flight describes arc of vertical circle before female; rising very high, plummets downward making explosive chirp sound at lowest point, then rises straight above female, hovers and faces her at top of ascent, delivering brief squeaky song. Male chases female to nesting area, then, with body held horizontally, male flies rapidly back and forth in short, tight arcs above female.

NEST:

Varied; often in oak, also vine, brush, and human-built structures; thick, well insulated, of plant down bound with spider's silk, lined with plant down and feathers. Building continues after eggs laid; lichen added to exterior. Usu built in 7 (range 3-14) days.

EGGS:

White, unmarked. 0.5" (13 mm).

DIET:

Includes spiders; tree sap.

CONSERVATION:

Winters s to c Baja and to n w Mexico. Range expanding to n. Widespread planting of eucalyptus and provision of artificial and exotic floral nectar sources year-round in gardens have led to permanent residency by many birds in coastal CA and likely increased abundance.

NOTES:

Fond of bathing, usu in dew-covered foliage. Post-breeding movement of migrants from coast to montane habitats. Defends feeding territories in nonbreeding season.

STANFORD. NOTES:

Abundant throughout campus, nesting in virtually any type of tree or tall shrub, even in areas with heavy human activity. Nesting occurs throughout the winter, spring, and summer, peaking in late winter and spring. Concentrations may be present at flowering trees, such as eucalyptus.

ESSAYS:

Nonvocal Sounds; Hummingbirds, Nectar, and Water; Hovering Flight; Hummingbird Foraging Bouts; Coevolution; Optimally Foraging Hummers; Range Expansion; Bathing and Dusting; Feeding Birds

REFERENCES:

Ewald and Orians, 1983; Powers, 1987; Stiles, 1972, 1982.
Except for Stanford Notes, the material in this species treatment is taken, with permission, from The Birder's Handbook (Paul Ehrlich, David Dobkin, & Darryl Wheye, Simon & Schuster, NY. 1988).