Hummingbird Facts
Q&A with Lanny Chambers in 2000
Characteristics
Q. What kind of bird are hummers most closely related to?
A. Most scientists think their closest relatives today are the swifts,
based on similarities in their bones, but swifts can't hover like hummingbirds--no
other bird can.
Life Cycle
Q. If we go back far enough, is there another type of bird (prehistoric) that is related
to the hummingbird that could fly like the hummers do?
A. There are no fossil hummingbird skeletons, probably because their
bones are too fragile. So we can only guess what they were like millions
of years ago. The first hummingbirds almost certainly lived in South America.
Ecology
Q. Do temperatures affect the amount of food a hummungbird needs?
A. Yes. Like all warm-blooded animals, hummingbirds burn calories from
food to maintain their body temperatures. When it's cold, hummers must burn
more calories, just like your furnace at home runs more often in cold weather.
If a hummingbird can't get enough food, perhaps because insects stopped
flying and flowers stopped blooming due to freezing weather, it may go into
a sort of suspended animation called torpor, where its temperature and heart
rate are reduced drastically to conserve energy. Torpor is a very risky
gamble for most hummers--a bird can't stay in torpor very long, and it's
betting that conditions will be better when it wakes up again. If the bird
wakes up again and still can't find enough food, it may starve to death.
It's thought that many hummingbirds use torpor occasionally to survive cold
nights, but Rufous Hummingbirds routinely go into torpor at night, probably
because they nest in Canada and Alaska, where it may freeze at night even
in July. It's the only way they can get through a cold night without having
to eat. Few flowers bloom or make nectar at night, so there's nothing to
eat after dark.
Q.
How does drought affect the hummingbird?
A. Drought often means that plants won't produce flowers or their
flowers won't have much nectar, and hummingbirds need flower nectar for
the energy to catch the insects that provide most of their nutrition. If
the local nectar supply falls off, a hummingbird will probably fly away
in search of a more reliable food source. If you have a feeder, your hummers
won't have to leave. In fact, during a drought you will probably see more
hummers at your feeder.
Q. Do all age groups (young and old) of hummingbirds migrate?
A. Normally, yes, except in species that don't migrate, such as Anna's
Hummingbird in California and other western states. In migratory species,
most individuals that stay behind in the fall are either birds that are
too old or sick to make another trip, or young ones that hatched very late
the previous summer and didn't have enough time before the end of the blooming
season to add the fat they'd need to make long flights. These birds tend
to wander slowly southward as far as they can go--in the east, that means
the Gulf coast, where most non-migrating Ruby-throated hummingbirds spend the winter.
Q. When will the hummingbirds be in Ohio?
A. Last year (1999) it was the first or second week of April, depending
on how far north in Ohio. That was about two weeks earlier than normal,
though. Will they be early again this year? It's too soon to tell, but if
you're making a map you'll know in a few weeks!
Lanny Chambers
Visit his site: hummingbirds.net
© 1997 – 2019 Journey North. All rights reserved.
