![]() ![]() ![]() Males may sing at any time of the year and both sexes make buzzy calls.Īnna’s hummingbirds breed earlier than other species, typically Dec–May. As they sing, they flash their rose gorget from side to side. Males sing a complex, buzzy 3-part song they first learn by imitating adults. A torpid hummingbird will be inactive, with feathers fluffed and eyes closed-do not disturb! In hummingbird torpor, breathing can be suspended for minutes, heart rate can dip to 50 beats/ minute, oxygen consumption slows, and body temperature can cool dramatically (one was documented at 8.8☌ 48☏). So how does a very small bird with a high metabolism survive cold winters? Obviously steady fuel is key, but so is torpor-a lowering of metabolism on cold days and at night. Hummingbirds have very high metabolisms, with resting heart rates of 420–460 beats/minute that can jump to 1220 in flight! Average body temperatures are 40☌ (107☏). It also eats small insects and spiders, and occasionally sap. Like other pollinators, the hummingbird does double duty as it drinks nectar, spreading the pollen dusting its face and bill to other flowers. The Anna’s hummingbird feeds primarily on nectar from a wide variety of plants, especially currant and gooseberry ( Ribes spp.), flicking its double grooved tongue repeatedly into a flower, retracting it, and then extending it again with slightly closed bill to strain the nectar into the mouth. Males and females only come together to copulate. Behavior and FeedingĪnna’s hummingbirds are not very social, aggressively defending territories and frequently conflicting with each other. These factors may also help explain this species’ unusual ability to overwinter in relatively cold climates, although it is not clear whether wintering birds are local breeders or migrants from elsewhere. This coincided with the spread of 3 new food sources: winter-blooming Eucalyptus trees, a growing buffet of exotic blooms in urban gardens, and ubiquitous hummingbird feeders. Since the 1960s, a dramatic range expansion brought Anna’s hummingbirds northward and eastward from their historical habitat in southern California chaparral. Females may have just a few streaks of throat color. The male’s throat flashes an iridescent rose gorget, and unlike other North American hummingbirds, this rose iridescence also covers his crown. Its body is greenish-bronze above and grayish-white below. The Anna’s hummingbird, Calypte anna, is a medium to large hummingbird (10 cm 4 in) that weighs about 2 pennies (4–4.5 g). The hummingbird family, Trochilidae, has over 300 species, all native to the Americas, with most in South America. But the resourceful Anna’s hummingbird can be found year-round up and down the West Coast, surprising us with its loud, flashy presence. In the dead of a Pacific Northwest winter, the last sound you’d expect to hear is the buzzy static of a hummingbird zipping through the canopy. ![]()
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