Signs of Spring Update: March 14, 2003
Many Lakes Still Too Frozen for Loons Loons are being seen in a few places, mostly near the coast. Look closely at today's migration map and see how they're progressing.
Don Davis, a naturalist in Toronto, Ontario, reported to us on March 13, "About 90 percent of Lakes Superior, Huron and Erie are frozen over. Lake Ontario is open, except around the north shore from about Newcastle, and east past Presqu'ile to the other side of Prince Edward County. This is southern Ontario's 10th coldest winter since 1948. February temperatures were 5 degrees below normal."
How has the ice on the Great Lakes affected loon migration? The Great Lakes usually open up before smaller northern lakes, and loons gather on the huge lakes and make frequent reconnaisance flights, searching for open water. Sometimes a pair of loons lands on "their" lake minutes after the ice disappears thanks to these flights. Compare the current migration map with last year's at this time. There are some important difference, especially on the shorelines of the Great Lakes, but so far the differences aren't too dramatic. Do you think the differences between this year's migration and last year's will become more dramatic as the season goes on? Or will the differences average out? Stay tuned! And make sure to report your first loon sighting! Get Your Eyes and Ears Ready! Even though it's too early for most of us to see loons, we can still brush up on our loon identification skills! Read the following guides, and then try answering the following question.
(To respond to this Challenge Question, please follow the instructions below.)
Looney Lift-Off
Loons always takeoff upwind, just like airplanes try to. This strategy
maximizes lift, which they badly need for takeoff, as you can see. (Loons
have incredibly high mass for their wing area -- which is called wing-loading.)
As the loon tries to take off, it runs along the surface of the water
into the wind, beating its wings hard. Loons weigh about 8 pounds, but
their wings are the size of the wings of some much lighter ducks. To take
off involves a lot of flapping, and a lot of work. Even with this speed,
there is often not enough air pressure beneath the wings to create "lift"
to get the loon up in the air. If there is a good head wind, that increases
the air pressure under the wings, allowing the loon to get up in the air,
but it doesn't look like there is much wind here. Notice how the film
clip ends with the loon close to the opposite shore. It will have to swim
back and try again. Look carefully at where its feet are, and how hard
it is to lift the body. Notice how as it tries to take off the bird holds
its neck straight out, compared to the curve of its neck when it was swimming.
Yo! Yodel Studies and Quiz If you heard two loons yodeling, could you tell which sound came from a larger loon? Meet Jay and learn some tips for listening to loon yodels: Then, using the sounds and sonagrams on that page, see if you can be a loon detective!
(To respond to this Challenge Question, please follow the instructions below.) Territory Time What makes a good loon territory? We humans need food and shelter to survive, and so do loons. Every spring each pair of loons needs to find a lake where they can find a good nesting place, where the food will be abundant enough to support the pair and their two chicks. How do they decide which lake to choose?
Jay Magers gave us the maps of four lakes in Wisconsin that he has studied. Learn how to judge a lake for quality loon habitat here: After you've learned how to judge territories from a loon's point of view, answer this question:
(To respond to this Challenge Question, please follow the instructions below.)
Kokomo Schwartz in New Hampton, New York, awoke on March 10 to more than fifty Red-winged Blackbirds. That same afternoon, Felicia Gulachenski, fifth grade teacher at Middle Road School in Hazlet, New Jersey, saw about a hundred blackbirds in her backyard. Redwing calls are one of the welcome signs of spring. If you want to learn how to recognize blackbirds and to hear and understand redwing calls, make sure to see our Barbara Wilson in Houston, Texas, wrote on March 9, "It must be spring today! The 13 purple martins at my house, spent most of the day singing and preening instead of out flying and bug catching. Their wonderful 'cher' and gurgling sounds fill the air with music." Listen to this exuberant sound of spring recorded by Lang Elliott:
On March 9, Julie Milham in Jasper, Georgia, found "a very large flock of Canadian geese heading north in the afternoon. They were so noisy, and so high up in the sky we had a hard time spotting them. Approximately 100 - 150 birds. Beautiful!" Sandhill Cranes have been gathering in huge numbers on the Platte River in Nebraska. People gather there to see them. The Rowe Sanctuary in Gibbon, Nebraska, is a great place to view cranes up close and personal as they awaken at first light and as they come down to the river for the night. Some cranes have left this Platte River "staging ground" now and are headed north. Several people in Wisconsin and Michigan have noticed Sandhill Crane in the past week.
Judy Rowe Taylor of Mukilteo, Washington, found and photographed two very interesting crows in the past couple of weeks. One was spitting out peanuts and corn kernals that it had stored in its throat pouch. The other crow had a badly deformed beak. To see more photos and learn more about these, see: We've had SO many new signs of spring this week! Wooly bear caterpillars, bluebirds, choruses of songbirds, crocuses and daffodils. Make sure you share YOUR spring observations with us. Just click on the owl button on any Journey North page. Oriole
Food Chain: Discussion of Challenge Question #8 Where Energy Comes From: Discussion of Challenge Question #9 Last time we asked, "How do plants get energy from the sun? Why don't food chains ever start with an animal getting energy from the sun?" Plants don't eat, though they often get minerals or other essential chemicals from the soil, the air, or occasionally by engulfing small animals. (The venus flytrap does this, for example.) But plants make the sugars they need using just carbon dioxide (from the air around them) and water in a special process called photosynthesis that requires light from the sun and special green pigments called chlorophyll. Animals cannot make their own sugar or other carbohydrates, so animals MUST eat in order to get food. Some animals eat animals, some eat plants, but if you go back to the original source of energy, all food chains must start with the sun's light giving energy to plants for photosynthesis to make sugar. How to Respond to Today's Challenge Questions:
1. Address an e-mail message to: jn-challenge-loon@learner.org Copyright 2003 Journey
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