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This is BirdNote.
Let鈥檚 assume for a moment that you have a yard that a pair of robins has nested in for 12 years. You may be surprised to learn that it hasn鈥檛 always been the same pair! Mortality rate is high in our familiar songbirds. For robins, it鈥檚 around 50% each year once young birds have fledged.
If a robin survives to midwinter, it lives an average of 1.7 years after that. The oldest robins in your yard might be about six years old, although one banded bird lived almost 14 years.
So in a dozen years you've probably had at least a half-dozen robins of each sex involved in nesting.
Robins and most other migratory birds don't maintain their pair bonds over the winter, so they mate anew each spring. But if the same male and female return to the same territory, they are very likely to mate again.
If the male has died, another male will likely take over the territory, and the living female may mate with him. Similarly, if the female has died, a new female will mate with the resident male. They may nest in the same shrub, if it's a favorable nesting spot, and to our eyes it looks as if the same pair of robins has returned.
To learn more, come to birdnote.org. I鈥檓 Mary McCann.
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Credits:
Producer: John Kessler
Executive Producer: Chris Peterson
Written by Dennis Paulson
BirdNote鈥檚 theme music was composed and played by Nancy Rumbel and John Kessler.
Call of the American Robin provided by The Macaulay Library at the Cornell Lab of Ornithology, Ithaca, New York. Song recorded by W.L. Hershberger. Call by R.S. Little.
Ambient recording by Kessler Productions.
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ID# AMRO-10 AMRO-10-2010-03-23-MM