TACOMA — With spring coming into full swing, birds will be migrating to Washington, occupying residents’ bird feeders. One bird in particular to keep an eye out for is the hummingbird.
Hummingbirds are the smallest migrating bird, according to the Seattle Audubon Center. While in flight, their wings flutter up to 80 times a second in a figure-eight motion and up to 30 mph, according to the Hummingbird Guide website. They’re also the only birds that move backward and sideways, according to the National Audubon Society.
To achieve their incredibly fast and complex flight patterns, a hummingbird’s body has adapted to withstand high blood-sugar levels that would be hazardous to humans. They must feed almost constantly.
“I’ve heard they need to eat as often as every 15 minutes,” said Suzanne Harkness, development and community engagement manager at the Tahoma Audubon Center in Lakewood, which aims to promote wildlife conservation and protection through education.
If you’re interested in befriending some birds this spring, Harkness and other online research centers explain what you should know about hummingbirds, including how their bodies work and ways to properly feed them.
Hummingbird behavior
To some people’s surprise, the tiny avian creatures inhabit only North, Central and South America, Harkness says.
Across the Americas, there are over 300 species of hummingbirds, according to the American Bird Conservatory. But Washington sees only a few of them.
Four species of hummingbirds regularly travel through the Evergreen State: the rufous, Anna’s, black-chinned and calliope hummingbirds. However, residents in the Puget Sound region get to see only the Anna’s and rufous varieties.
Harkness says that in the last 50 years, the Anna’s hummingbird has stopped migrating, so it’s now a permanent, year-round resident of Washington. Rufous birds, on the other hand, migrate to Washington from Mexico during spring and summer for breeding. Male hummingbirds are polygamous, meaning they mate with several females and leave the parenting duties to the moms.
The birds, in general, are very territorial and have bold temperaments. Males in particular will stand their ground (or air) when it comes to guarding their territory or food supply.
“They’re really not shy,” Harkness says. “I myself have been buzzed by them when going to refill the feeder … like they’ve buzzed my head.”
Function and flight
Hummingbirds possess incredible metabolism, over 70 times higher than a human’s. While not flying, the bird’s heart beats around 400 times per minute, Harkness says. But while in flight, it can exceed 1,200 beats per second. For comparison, the normal resting heart rate for an adult human is 60-100 beats per minute. For a young adult human, a high heart rate would be somewhere between 140 and 180 beats per second.
To maintain its highly active body from overworking, a hummingbird enters a semi-hibernation state while sleeping called torpor. In this state of hibernation, the bird will often sleep upside down. Their bodily functions also drastically shift so that they can conserve calories:
- Body temperature drops as much as 50 degrees.
- Breathing slows or is totally absent.
- Metabolic rate slows as much as 95 percent.
- Heart beat slows to as low as 40-50 beats per minute.
- The bird expends about 50 percent of its normal energy.
To an unassuming observer, it may appear that the sleeping bird is dead. But unlike other birds, this near-death state is normal for the hummingbird.
Tips for feeding
It’s well known that hummingbirds are attracted to sugar-rich nectar, which they need to maintain their high blood-sugar and glucose levels. The birds also eat other plants and bugs like gnats and flies.
Harkness and other bird society websites have tips on what you can do to safely feed a hummingbird.