|Send a Songbird
to the Neotropics
About 5,000,000,000 (that's FIVE BILLION!) birds are now preparing to leave North America for the winter months, and over half of them are babies. Most were born in June and July. They're less than four months old and haven't had much experience flying, but these youngsters are full grown and on their own. And they're now about to face the most difficult time in their lives.
Fortunately, these little ones are survivors. Already they've managed to struggle their way through a strong eggshell all by themselves, and lived through a lot of dangers such as:
Migration is the first time in their lives that most baby birds will be away from their
parents. They are still inexperienced about finding food and shelter, and suddenly they will be in strange places
where the plants and animals will be different from where they've spent their whole lives. All the dangers they've
ever seen before--and more-- await them as they set out on their first long journey to an unfamiliar land far away.
A. Lead a class discussion about what it would be like to be all alone, searching without help for a destination thousands of miles away that you've never been. What problems might you face? How would you deal with them? Challenge the students to write an essay in their journals about how they'd feel if they were a migrating bird, and how they might successfully complete this journey.
B. Numbers of every species are highest at the end of the breeding season, and drop until the following spring. For example, a typical oriole pair may produce a brood of four babies in the summer. By the following year, of the six orioles in a family, on average only two will be back. Calculate the death rate of this typical oriole family.
C. Look at U.S. Fish and Wildlife Service's Breeding Bird Survey data for the species your class is following on its Journey South, and for any other species you may be interested in. Are the populations increasing, decreasing, or stable over the continent? Are the populations increasing, decreasing, or stable in your state or province?
1. If a species is declining, why don't pairs simply have more babies every year? What might limit the number of babies that a pair of birds can raise each year?
2. There are different ways that scientists count birds. Breeding bird surveys count singing males on their territories. Radar studies count every "blip" known to be a bird on a radar screen. Migration counts tally the birds that fly along a coast or ridge from a vantage point with high visibility. What are advantages and disadvantages of each method?
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