Oriole Migration Update: May 4, 2000
Orioles Flooding Northward! Spring migration has reached fever pitch across the mid-continent, with millions of songbirds returning from the Neotropics. This was a BIG week for orioles, with more than fifty new sightings. The first arrivals have swiftly moved northward, and we even have one report of nest building in Slaughters, KY (37.51N, -87.50W)! Compare this week's maps with last week's. How would you summarize the migration data by filling in these blanks? "Orioles have now been reported in ____ U.S. States and __ Canadian provinces. This compares with _____________for last week." A Swift Trip In contrast to some other species, oriole migration occurs swiftly. As you map their migration, think about this:
Weather for the Birds Dear Students, The orioles have arrived! The front I talked about in my April 20th report brought lots of migrants to our shores, including lots of Baltimore Orioles. When the front moved through here, it forced many birds to land. . . . A few days after the front passed, the winds shifted to the south, and many of the birds continued north. Maryland, New Jersey, Ohio, and Illinois have all reported large numbers of migrants. A second cold front followed soon after, and while it wasn't as strong, it still brought lots of birds. At my study site this week I saw the first orioles for this area, along with the first cuckoos, a Blackburnian Warbler, and Yellow-breasted Chat. The front I just mentioned has stalled over the Carolinas, so that should keep the birds around the Southeast for another day or two. Another cold front is moving in from the west. The Gulf coast states should expect good birding later in the week, and I should see more birds by the weekend or early next week. Orioles should be especially common, along with cuckoos, some of the thrushes, and chats. As I mentioned last time, migration will be winding down soon here in the south, but farther north things are picking up, so don't put away your binoculars yet. Once migration ends, there is still plenty to see. Take Care, David See David's full weather report at:
Using the Data: Weather and Migration What weather systems might have swept the orioles northward so quickly? See what you can discover: 1. First play with the data for awhile. You might count the number of sightings per day, then make a graph so you can see the peak migration dates. And/or, look at the map for that day (on the WWW), then back at the data. Are there certain regions where, in a single day, many orioles appeared? 2. Now look at the weather maps for the 3-4 days leading up to the arrival:
On the Lookout to Let Us Know Remember: Watch for the first male if you haven't seen him yet, and the first signs of nest building--and please report to Journey North! The female usually arrives a few days after the male, and she's the one who builds the nest. Enjoy this personal field checklist to guide your observations and reporting:
What's the Name of That Song? These eye-catching, bright orange and black birds are the size of blackbirds, but they stay high in trees. If you learn the song, you will look up the moment you hear it, and might be rewarded with a glimpse of the oriole. Orioles have a rich, full-throated whistle. The melody and rhythm can vary greatly, but the tone stays the same.
Swinging Nurseries No one needs to tell orioles how to build their summer homes and nest nurseries. They follow the "nest-building blueprints" in their brains, and instinctively know how to build the perfect structure to hold the eggs they're about to lay. Oriole nests are so well made that they will last for several years in the worst kind of weather. How do they do it? What's unusual about oriole nests? What materials do they use? How long does it take for these master weavers to create their swinging nursery pouches? Imagine you're an oriole and it's nest-building time. Find fascinating facts and step-by-step directions for building that marvelous hanging-sack nest with this terrific Journey North lesson:
Bird Brains! "Orioles have thoughtfully removed bee guards from (hummingbird) feeders for easier access to sugar water." (pjhurst@quik.com) This doesn't surprise Journey North's Julie Brohphy, whose yard in Victoria, MN has orioles every year. Julie says, "They are clever! I've also seen them grab and fling wasps away that compete for the nectar at the feeders." So, consider "bird brain" a compliment. . .and entice some orioles to your yard for interesting observing! Feeders like the one in this photo help attract orioles. The spike holds orange and apple halves. The removable plastic cup is for mealworms, grape jelly, raisins, or other oriole-pleasing fruits. Invasion From South of the Border Exactly how many migrants have arrived from the Neotropics over the past few weeks? In an article called "Silence of the Songbirds" (National Geographic, June 1993), a scientists named Fr. Sidney Gauthreaux was asked this question. He estimate that at peak migration time, as many as 45 million songbirds arrived in a single night along a 300-mile stretch of coastline between Corpus Christi, Texas, and Lake Charles, Louisiana. How does he know this? Since the 1960s he has used radar to measure migration across the Gulf of Mexico. Check out the June 1993 National Geographic magazine for Dr. Gauthreaux's article and photos. Here They Come! Discussion of Challenge Question #9 "How many orioles would weigh a ton?" (Hint: Baltimore Orioles weigh 30-40 grams.) About 22,222 orioles! If one oriole weighs 40 grams, that's .09 pounds. A ton is 2000 pounds, so divide 2000 by .09 for an answer of 22,222.
Flight By Night: Discussion of Challenge Question #10 "Name some reasons why songbirds would migrate by night rather than day." Mrs. Boyle's 4-5 multi-age class in Ogdensburg, NY considered: "Song birds migrate at night rather than day because they sing in the day. Plus there are not a lot of people up at night and it's safer. Songbirds eat during the day plus sleep in the day and travel during the night." Right! Many songbirds, including orioles, fly at night and land to rest and feed during the day. The students are right about night being safer, too. Hawks and other songbird predators can't fly at night. There are many other reasons, too. At night, the winds die down so flying is smoother. The temperatures are cooler so the exercising birds don't overheat. (Flapping wings is real exercise!) Seeing the stars helps the birds navigate. They can fuel up during the day for their long night flights.
How do Birds Forecast the Weather? Discussion of CQ #11 We asked, "How do birds sense weather conditions, and know whether good or bad migration weather might be coming?" Birds can actually feel changes in air pressure in their inner ear. When the pressure goes down, birds feed a lot more, as if anticipating a storm. So birds literally have a sixth sense--and a built-in barometer! How to Respond to Today's Challenge Question: Please 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 #12. 3. In the body of your message, give your answer to the question above.
The FINAL Oriole Migration Update Will Be Posted on May 18, 2000 Copyright 2000 Journey North. All Rights Reserved. Please send all questions, comments, and suggestions to our feedback form
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