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Oriole Migration Update: March 15, 2001
Today's Report Includes:
- Dr. Aborn's Weather Forecast for the Birds
- Two Different Birds, or Two Similar Birds? Challenge Question #2
- Get Set For Journey North's Oriole Study
- Unpave the Way For Orioles
- Try This! How Do Birds Learn Songs?
- Coffee Can Brew Trouble for Birds
- Teacher Tip: Tropical Travelers Coming Your Way
- Try This! Nest Hunt
- Home Sweet Habitat: Discussion of CQ #1
Dr. Aborn's Weather Forecast for the Birds
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David asks, "If you look at Wednesday's map (3/15), what do you see?" Who should keep their eyes open for birds arriving from the tropics and forced by the weather to land? Find the weather map and the answer to this question with the rest of David's full letter here:
Two Different Birds, or Two Similar Birds?
While we're waiting for the orioles to come back from their winter range, it's a good time to brush up on some basics. Did you know that people have puzzled over the question whether Baltimore and Bullock's are two different birds or two similar birds? Both are northern orioles, but the Baltimore and Bullock's had been lumped together due to observed hybridization (interbreeding). Who decides whether to lump similar birds into one species or to further split up an existing species? The American Ornithological Union (AOU) decides. They look at the bird's appearance, voice, natural history, breeding biology and DNA analysis. Generally, the AOU needs many reasons before they decide whether to lump or split.
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Female Bullock's Oriole |
Male Baltimore Oriole |
Oriole Range Map |
New information has changed the thinking. Recent DNA work has led the AOU to reverse its decision. These two orioles are once again separate species. Pull out a Field Guide to birds and study the photos and range map on this page and see how many differences you can pick out. Then send us your answers to:
Challenge Question #2:
"What differences between Baltimore Orioles and Bullock's Orioles can you name?"
(To respond to this question, please follow the instructions below.)
Get Set For Journey North's Oriole Study
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Here's a reminder about what to report to Journey North:
- FEEDER UP: As soon as you place your oriole
feeder outside, report to Journey North. Now you're ready to watch for your first
orioles!
- FIRST ORIOLE SIGHTING: Let us know when your
Oriole safely arrives after the long migration from Central America.
- "LEAF-OUT" of your trees. For many
songbird species, the timing of spring migration may be related to leaf-out. When
leaves emerge, so do lots of insects. Songbirds may fuel their migration by following
the leaf-out, and eating the millions of insects now available. With your help, we'd
like to test whether these spring events are inter-related.
- FIRST ORIOLE NEST-BUILDING: Usually the females are seen flying with nesting materials such as plant fibers or string. For tips to attract Mrs. Oriole, see:
Unpave the Way For Orioles
Join thousands of other students in preparing habitat for orioles. It's pretty awesome to realize that by creating backyard refuges with these simple suggestions, you can help ensure that the annual migrations to and through your region continue! See:
Try This! How Do Birds Learn Songs?
Did you ever wonder how birds of a species sing the right songs? Many species--including Song Sparrows and Orioles--inherit their songs. These birds do not learn the calls of other species no matter how much they may listen to them.
But the trick is, many birds DO learn the songs they sing! Mockingbirds and starlings learn virtually ALL the notes they sing from their environment. Orioles are one of the many species that have an internal, inherited "template" song, but they learn their regional dialect from the Orioles in their environment. Bird expert Laura Erickson says, "One of the ways I could always tell during May if the orioles I was hearing were my local ones or migrants passing through was by their song." Of course, those of you who didn't know your local oriole dialect from last year wouldn't recognize it to tell it from the migrants' dialects this year. It's certainly not as easy as recognizing a southern person's dialect from a Midwesterner's. But if you're REALLY interested, how could you find out? In the meantime, give it a try. See if you can hear the difference between the dialects of three Baltimore Orioles:
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Listen to one oriole
dialect |
Listen to a second
oriole dialect |
Listen to a third
oriole dialect |
Coffee Can Brew Trouble for Birds
What's the connection between coffee and the birds that breed in our backyards? The Songbird Foundation tells us that the single greatest threat to the songbird's survival is the growth in sun-grown coffee production, which is now the most popular method of growing coffee in Latin America. The destruction of forests throughout the tropics has been devastating to migratory bird populations as well as resident species. In the mid-elevations of Mexico, Central America, the Caribbean, and Colombia, most of the forests still standing are in traditional coffee plantations. These provide the last refuge for birds that have lost their habitat to the vast destruction of tropical forests.
Once people hear about shade coffee, many want to buy it. Do coffee drinkers in your family know about shade coffee? Is shade coffee available in your community? For help, see:
Teacher Tip: Tropical Travelers Coming Your Way
This week's report is full of tips for attracting and helping orioles. Why is attracting orioles such a big deal? Conservationists are concerned about some Neotropical migratory species because fewer and fewer birds return each summer. For background information about this conservation issue, read "Silence of the Songbirds" in National Geographic's June 1993 issue (pages 68-90). For more background, and to find out which Neotropical migrants breed in your state or province so you can choose one to study as a class, see:
Try This! Nest Hunt
Even in winter you can learn whether
orioles come to your neighborhood. Look for their nests hanging in the leafless trees.
The nests are strong and last at least a year. This spring, you can check out these
trees to see if they're a favorite nesting place. You can help make sure this important
tree and others like it are saved for the orioles.Home Sweet Habitat: Discussion of Challenge Question #1
Last week we asked: "What type of habitat do orioles prefer on the wintering grounds? What are some threats to this habitat?"
According to sightings of naturalist Carrol Henderson, more orioles are seen at elevations of sea level to 1800 feet, or tropical (lowland) forests. Clearing of these forests for fuelwood, farmland, and communities is a real threat to oriole habitat.
How to Respond to Today's Challenge Questions
IMPORTANT: Answer only ONE question in each e-mail message.
1. Address an e-mail message to: jn-challenge-oriole@learner.org
2. In the Subject Line of your message write: Challenge Question #2
3. In the body of your message, give your answer to the question above.
The Next Oriole Migration Update Will Be Posted on April 5, 2001
Copyright 2001 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form
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