In the News -
December 2007
Humming while they work
HOPE, Ark. - The hummingbird is one of the more popular birds that bird
enthusiasts enjoy watching, for many reasons, says Gerald Alexander, Hempstead
County staff chair with the University of Arkansas Cooperative Extension
Service.
"Hummingbirds are remarkable creatures," Alexander noted. "When you see their
antics around bird feeders, you can’t help but be captivated by the speed and
agility of these tiny creatures."
The wings are a blur and that’s because a hummingbird’s wing beats about
60-80 times a second in normal flight and up to 200 times a second in courtship
dives."
The average heart rate for a hummingbird is about 250 beats a minute while at
rest and up to 1,260 beats while flying.
The heart rate can be reduced dramatically when the bird encounters
unexpected cool weather by going into a trance-like state called torpor, a type
of hibernation where the body temperature and the body’s metabolic rate and
heart rate slows. Once environmental temperatures rise, the bird can resume
normal activities.
You won’t see hummingbirds this time of year because they pack their bags and
head south of the border when cooler weather hits.
"Hummingbirds migrate two times a year. In the spring, the hummingbird
migrates from Central America to its breeding grounds in North America,"
Alexander says. "Some hummers migrate as far north as Canada. In the fall, the
birds migrate back to Central America."
As any duck hunter knows, migration is not unique to the hummingbird.
Alexander says hummingbirds are loners, preferring to migrate alone instead
of in large groups like other birds.
They also decide individually when to bid adios and head south. Some leave as
early as July, while others leave in September, or when the cooler weather
forces them to leave.
"Homeowners who place hummingbird feeders around their homes shouldn’t remove
the feeders in an attempt to force the hummingbirds to leave," the county agent
says.
"The hummingbirds you see around your feeders today are likely not the same
birds you saw last week," Alexander says. "As the hummingbirds from farther
north begin to fly south, they will stop wherever available food can be found.
Those birds that decide to migrate later will still need to find food as they
begin their journey south. Removing your hummingbird feeders too soon may mean
the difference between life and death for the late fliers."
Hummingbirds also decide individually what migration route they take. Most
fly over land and stop frequently along the way, while others decide to take the
riskier non-stop 18- to 20-hour trip over the Gulf of Mexico.
As you might imagine, the Gulf trip takes a physical toll on the birds.
"The hummingbirds that choose to fly over the Gulf will lose more than half
of their body weight," Alexander says.
The Cooperative Extension Service is part of the U of A Division of
Agriculture.
December 7, 2007
Media Contact: Lamar James
Extension Communications Specialist
U of A Division of Agriculture
Cooperative Extension Service
(501) 671-2187 or (501) 753-0207
ljames@uaex.edu
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