Why Such Short Daily Flights? Excerpt From the Nov. 22, 2001 Journal of Ultralight Pilot Joe Duff Joe Duff, Operation Migration Project Leader Our daily migration legs only last an hour or two and cover as little as 40 miles at a time. Why? Our journeys are small compared to the daily flights of wild birds. Normally cranes migrate during midday when the sun's heat is the strongest and creates thermals (rising columns of air). The cranes soar on these "elevators" like hawks or eagles, seldom flapping their wings. Under good conditions they can stay aloft for hours, covering hundreds of miles with little effort. We are not able to fly the way cranes do. Our aircraft, although state-of-the-art, perform at a fraction of cranes' ability. Instead, our captive-bred birds learn to use the wing of the aircraft and the wake it creates to "surf" through the sky and ease their workload. This can only happen when the air is smooth and the wing remains stable. If we encounter turbulence and the wing begins to bounce around, the birds must move away and follow from a safe distance. When this happens they are forced to flap-fly, and they soon tire. Our flights are therefore limited to the calm air of early morning. That's also when cooler temperatures prevent the birds from overheating. This learned behaviour is temporary. Once free and on their own, they will instinctively fly like wild birds and use thermals to make their way north. Try This! Journaling Questions Why are ultralight flights short compared to the distance wild birds can travel? Scan the second paragraph of Joe's entry above and pick out one sentence that tells the main idea of the paragraph. Joe is Canadian, so a few words are spelled the Canadian way. Can you find two examples of Canadian spellings? The successful journey south of the ultralight-led Sandhill cranes was an example of instruction and instinct combined. Explain what that means.   Journey North is pleased to feature this educational adventure made possible by the Whooping Crane Eastern Partnership (WCEP). This Season Teachers Kids Orientation Registration Search Copyright 1997-2009 Journey North. All Rights Reserved. Questions or comments? Contact us.