The
four species of hummingbirds that visit Washington are only 3 to
4 inches long from end to end. Their bodies are no bigger than the
end joint of your thumb and they weigh no more than a nickel. Yet
they expend more energy for their weight than any other animal in
the world. This energy is used mainly for flying and for keeping
their tiny, heat-radiating bodies warm.
Hummingbirds
are like living helicopters. They can hover, fly straight up and
down, sideways, backwards and even upside down. This is possible
because their wings rotate from the shoulder instead of the wrist,
so they get power from both the downbeat and the upbeat. While their
average flight speed is 27 miles per hour, they can travel up to
50 miles per hour, with their wings beating 70-80 times a second.
Although hummers
often nest in lower tree branches and bushes, people rarely notice
the golf ball-sized nest. The female assumes all nesting duties.
She sculpts a cup of plant parts, mosses and lichens held together
with spider webs for her nest. In it she lays 2 pea-sized, white
eggs and incubates them for 14 to 21 days. Once hatched, she feeds
the young ones a rich diet of regurgitated nectar. After about 25
days the youngsters leave the nest to survive on their own.
In this country,
hummers are eaten by kestrels, magpies, jays, crows, cats, and bullfrogs.
Storms and killing frosts are also responsible for some deaths.
Most hummingbirds
eat nectar from flowers for instant energy, and insects for protein
to build muscle. Protein meals include aphids, small insects and
spiders. Hummers meet their high energy demand by eating more than
half their weight in food and drinking up to 8 times their body
weight in water every day. To eat and drink, a hummingbird’s
tongue is divided at the end into two rolled, muscular halves. These
halves act like a double trough to soak up nectar and water, while
the brushy tips of the tongue trap insects.
In cooler climates
like Washington, hummingbirds gather food in their tiny crops (throat
pouches) before dark. Then they slowly digest this stored food throughout
the night. Hummers also lower their body temperature and heart rate
at night to save energy and ensure that the food supply in their
crop will last until morning. |
