Hummingbird Migration Update: March 11, 2003


Today's Report Includes:

• Following the Flowers: Rufous Hummingbirds On the Move!
• Why So Early? Link to Data and Challenge Question #6
• The Nectar Trail: Discussion of Challenge Question #3 and Link to Lesson
• Steady Advance: Ruby-throated Hummingbird Migration Map and Data
• A Bird in the Hand: How Hummingbirds Are Banded: Challenge Question #7
• Sleepy Time for Rufie: Discussion of Challenge Question #4
• Happy Trails: Discussion of Challenge Question #5

Rufous Hummingbird photo copyright by Jerry Blinn

On March 10, Mike reported "Rufous Hummingbirds, including many females, are now being regularly seen as far north as Vancouver Island, British Columbia. The first report from the foothills of the Cascades has come from Idleyld, Oregon, at an elevation of about 1600 ft." It's colder at higher elevations, so flowers take longer to bloom in the mountains. Why do hummingbirds appear high in the mountains after they've been seen along the coast at more northern latitudes? There will be lots of clues in this report!

Rufous Hummingbird Migration Data Migration Map Courtesy of Mike Patterson Neawanna Wetland Ecological Observatory

If YOU see a Rufous Hummingbird in the West, make sure you report it to Mike Patterson. And if you see hummers, make sure you let him know if any flowers are blooming, too!

Rufous Hummingbird scientist Mike Patterson, holding another bird with a rufous breast--an American Robin!

Why So Early?
Why are the hummingbirds so early this year? As Mike has been discovering, their migration is closely synchronized with opening flowers. He added in his March 3 letter that the Salmonberry is right on schedule, and that some other flowers were very early, just like the migration. How early is early? Using data collected over the last three seasons, Mike compared the previous earliest records to those sent in this year. He figured out the answers to these questions, but YOU can do the same thing. Find Mike's data here:

• How Early is Early?

Then sharpen your pencils and get ready to calculate the answers to

Challenge Question #6:

1. How many days earlier did each location report hummingbirds? (We've done the first two for you.)
2. How many sightings this year were LATER than a previous early date?
3. What date did the first Rufous Hummingbird appear in Gig Harbor, Washington, in 2003?
4. What date did the first Rufous Hummingbird appear in Philomath, Oregon, in 2003?
5. Which place had the biggest difference between this year's early date and the previous one?
6. The average is _________________days ahead of past records.

(To respond to this question, please follow the instructions below.)

Nectar Corridors credit M. Hosier

Why does it make so much sense that hummingbird migration coincides with opening flowers? Hummingbirds feed on nectar, which they get from flowers. The flowers that are the best source of nectar for hummingbirds have a shape that allows easy hummingbird feeding and have a color attractive to hummingbirds. The flowers are adapted to provide food for hummingbirds because while the hummingbirds are feeding at them, they pick up pollen on their head and face, and then drop this pollen on other flowers.

This reminds of Challenge Question #3. We asked, "How do hummingbirds help flowers?" They transfer pollen from one flower to another. This is called pollination, which is necessary for flowers to grow seeds. Pollination is critical for plant survival, and nectar is critical for hummingbird survival, so hummingbirds and flowers are dependent on each other. Hummingbirds aren't the only migratory pollinators that follow a nectar trail. Two other species that we meet on Journey North pages do, too. Where do they come from and where do they go? How do YOU benefit from migratory pollinators? Find answers and more questions here:

• Who Follows the Nectar Trail?

The glowing iridescence of a male Ruby-throated Hummingbird is a welcome sight!

This Ruby-throated Hummingbird is held by master bander Nancy Newfield. (Photo by Laura Erickson)

A Bird in the Hand: How Hummingbirds Are Banded
Is a bird in the hand really worth two in the bush? Sometimes--especially when that bird in the hand is put back into the bush! When a bird is banded, and then released, scientists can learn a lot about it, especially if anyone ever finds that bird again.

Nancy Newfield is a hummingbird bander in Louisiana. She traps hummingbirds in special cage traps, and then examines, bands, measures, weighs, and marks them and releases them. Over many years of banding, Nancy has learned a lot about hummingbird migration patterns and life spans through her work. How do banders catch hummingbirds? How do they get a tiny band on a hummingbird's leg? For a step-by-step close look at how Nancy bands hummingbirds, see

• Nancy Newfield: Hummingbird Bander

Then think about this question:

Challenge Question #7:
"Why does Nancy Newfield put the band on a hummingbird before she weighs or measures it?"

(To answer this question, please follow the instructions below.)

Gerry's yard has several features that would be attractive for a hummingbird in winter.

• Eastern Red Cedars. (We think Rufie probably took shelter in the thick, protective branches of these cedars at night.)
• Trees that provide food for sapsuckers. (Sapsucker holes provide sap and insects for hummingbirds.)
• Bird feeders and habitat that attract lots of other birds. (Hearing other birds tells little birds that an area is a good place to be, and that if a predator enters the scene, there will be a good chance that some bird will notice and give warning.)
• Hummingbird feeders. (When a hungry hummingbird is searching for food, it looks for the color red. And hummingbirds are good at recognizing feeders.)

Photo of immature male Rufous Hummingbird by Bill Hilton, Jr.

January is when Rufous Hummingbirds start migrating, so it's possible, and even likely, that Rufie headed west. Other possibilities are that Rufie might have died or Rufie might have moved to another yard. Journey North's science writer Laura Erickson thinks these aren't too likely. The banders noted that Rufie had plenty of body fat, and so was in good condition. Rufous Hummingbirds are very speedy, and have an easy time evading hawks. And the temperature and weather conditions on January 3 and 4 were milder than many days that Rufie had survived. By offering two different food mixtures, and having sapsucker food available too, Gerry's yard was perfect for Rufie. There are so many cases of Rufous Hummingbirds remaining in a single yard for a whole winter that Laura thinks this is what Rufie did, too.

We don't know if Gerry will ever see Rufie again, but we do know that many Rufous Hummingbirds do return year after year to the same yard. If Gerry ever sees a Rufous Hummingbird in her yard again, there will be some clues about whether it's Rufie. First, he will NOT look the same as Rufie did this year. This year Rufie was an immature male. Next winter he will be a mature male, with a bright red throat. If an adult male Rufous Hummingbird appears, Gerry will look carefully to see if he has a leg band. If he does, she will be pretty sure he's Rufie, but won't be certain until a bander comes, traps Rufie, and looks at the number.

IMPORTANT: Answer only ONE question in each e-mail message.

1. Address an e-mail message to: jn-challenge-humm@learner.org
2. In the Subject Line of your message write: Challenge Question #6 (OR #7)
3. In the body of EACH message, give your answer to ONE of the questions above.

Copyright 2003 Journey North. All Rights Reserved.
Please send all questions, comments, and suggestions to our feedback form