Time Out from Feeding
Eating Big Amounts
Hummingbirds are famous for the amount of food they eat. One ornithologist calculated
that they eat at least half of their body weight in sugar (not even counting the
water in nectar!) every day. You'd think they'd need to spend every waking moment
eating to get that amount of food, but they don't. As a matter of fact, some researchers
have found that they make feeding flights 14 to 18 times every hour, and each feeding
flight lasts less than a minute. Hummingbirds don't spend as much of each hour feeding
as we might think.
Four Minutes From Full
Hummingbirds have a tiny stomach and crop (the little storage
pouch in their esophagus). Once these are full, the hummer can't eat any
more until the crop is about half empty again. It takes about four minutes
to drain about half the nectar into the stomach and intestines, and then
the hummer takes off again.
Taking a Break
What do hummers do when not eating? Mostly they sit on tiny branches
or wires. They look like they're resting, but their bodies are
busy digesting. Their eyes and
minds are busy studying the world. Journey North science writer Laura
Erickson sees them perched a lot. She says they seem to notice
everything going on around them.
They make little chittering sounds when eagles and other predators
fly over, and even seem to follow her with their eyes and bill.
Try This! Journaling Questions
- Why does it make sense that even when hummingbirds are sitting still, they're
watchful for any potential threats? (Hint: Think about a hummer's only means of defense
and escape.)
- If hummingbirds
make feeding flights 14 to 18 times every hour during daylight, and
each feeding flight lasts less than a minute, about how much time in
each daylight hour do hummers feed?
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