| Species: Anna’s Hummingbird
Calypte anna
Description:
The quintessential
urban hummingbird, Anna’s Hummingbird has shown remarkable
adaptability to the urban environment. In recent times it has
expanded its range northward and eastward, exploiting exotic flowers
and feeders in urban and suburban gardens. The only hummingbird
known to over winter in Southwestern British Columbia.
Identification:
A medium-sized
chunky hummingbird with medium-length straight black bill, dingy
medium to pale gray underparts, medium-length to long tail. Inner
primaries all approximately equal width, outer primaries angular at
tip.
Adult Male:
Bright green to bluish green above. Gorget is rose red to coppery
red, with moderate extensions at corners; crown and separate patch
behind eye same color as throat. Upper breast medium to pale gray,
usually slightly mottled. Pale feather edges give green underparts a
scaly appearance; pale midline stripe faint or absent. Long, deeply
notched tail extends well beyond wingtips. Outer tail feathers are
gray, darker at edges bordering paler translucent patches; R5
narrow, rounded at tip.
Adult Female:
Bright green to bronze-green above, medium to pale gray below.
Gorget markings vary from bronze-gray mottling to a ragged-edged
triangle, oval or diamond of rose red to coppery iridescence.
Slightly notched to double-rounded tail extends to or beyond
wingtips. Tail feathers broad, rounded; R3-5 banded in dull
gray-green, blackish, and white. Bill is straight to very slightly
decurved.
Juvenile: Male:
Resembles adult female but with pale feather edges, heavier mottling
in gorget with larger iridescent feathers; R5 broad, rounded, with
thin line of black ext ending into white tip along shaft.
Female: Very similar to adult female, usually with dull gray
mottling in gorget with or without a few iridescent feathers
centrally; may have more white in R2. Best distinguished by plumage
condition.
Similar Species:
Costa’s Hummingbird is smaller, with shorter tail, paler underparts
with pale midline stripe creating a distinct ‘vest’; gorget is deep
purple to violet, with longer extensions at corners. Females and
immature males have thinner bills, shorter tails that are often
pumped or wagged in flight; underparts are paler, plainer.
Black-chinned Hummingbird are slimmer, with longer bills; paler,
plainer underparts; inner primaries graduated in width. Tail is
usually pumped or wagged in flight. Call note is a soft tchew or
tchup.
Behavior:
Typically holds tail still while hovering, unlike Black-chinned and
Costa’s. Takes nectar at a variety of flowers, including native
charparral currant, fuchsia-flowered gooseberry, wooly blue-curls,
pitcher sage, California fuchsia, red bush-penstemon, western
columbine, and bush monkeyflower; also exotics such as citrus, tree
tobacco, aloes, bottlebrush and eucalyptus. Feeds extensively on
insects, including gnats, midges and whiteflies, especially during
winter. Occasionally observed eating sand and ashes, probably to
supply minerals.
Adult males defend
feeding territories and sing year-round; young males begin singing
by late summer, often from concealment. Dive display is complex,
noisy. Male sings buzzy notes while hovering over the object of the
display, then climbs for 7 to 8 seconds on a wavering trajectory to
a height of 65 to 130 feet before plunging the same distance in a
mere 2 seconds. The dive ends with a shrill squeak as the displaying
bird passes the object.
Habitat:
Breeds in chaparral, coastal scrub, evergreen-oak woodland, riparian
woodland, oak savannah, orchards, parks, urban gardens, sea level to
5,700 feet. Nonbreeding birds often move to higher elevations and
inland into pine-oak forest, pine-fir forest, mountain meadows, up
to 11,000 feet. Population density and distribution outside coastal
southern California dependent in large part on availability of urban
habitats.
Information:
No subspecies are
recognized. Anna’s and Costa’s form a super-species, isolated
primarily by habitat preferences. Hybrids between the two are
common. Though song is now known to be more the rule than the
exception among North American hummingbirds, the song of Anna’s was
among the first to be studied and is still among the best known of
all hummingbird songs.
The name of this hummingbird honors Anna Masséna, duchess of Rivoli
and a patron of the sciences.
Conservation
Status: More study needed.
This species has
benefited greatly from human activities. Replacement of native
chaparral and esert scrub with irrigated gardens and parks has
permitted expansion of range north into Canada and east into the
Mojave and Sonoran Deserts. Anna’s appears to displace Costa’s as
natural desert gives way to residential and recreational
development. Additional study needed to determine how these two
species interact in urban habitats.
References:
Williamson, Sheri L. Peterson Field Guides – Hummingbirds of North
America. New York: Houghton Mifflin, 2001.
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