In spring, millions of songbirds - like this Orchard Oriole - migrate north across the Gulf of Mexico, from the Yucatan to the southeastern US. When birds encounter storms or headwinds, many may die. Why risk such an end, when they could migrate north along the length of Mexico? It's likely that many birds evolved to take the potentially perilous trans-Gulf route because it is direct and considerably faster, putting the birds on the best breeding territories more quickly.
Written by Bob Sundstrom
This is BirdNote! [waves, coastal]
In spring, millions of songbirds migrate north across the Gulf of Mexico, from the Yucatan to the southeastern US. One author describes this crossing as “one of the greatest crapshoots in bird migration.” When the weather is fair and tailwinds strong, the flight — while metabolically taxing — is completed quite handily. But when birds encounter rainstorms or headwinds, they struggle mightily, and many may die.
[Strong wind and rain]
After fighting sustained bad weather, birds reaching the US coast are exhausted and famished. They drop into the nearest shrubs and trees by the thousands. [Begin Tennessee Warblers calling] Picture a shrub loaded with colorful tanagers and orioles, such as these Orchard Orioles. [Orchard Oriole singing] Or a tree full of brilliant warblers! These are Tennessee Warblers! [Tennessee Warbler singing]
But why risk exhaustion or a watery demise, when birds could instead migrate north along the length of Mexico? [Tennessee Warbler singing]
It’s likely that many birds evolved to take the potentially perilous trans-Gulf route because it is direct and considerably faster. The trans-Gulf flight saves nearly a week of travel time, putting birds on the best breeding territories more quickly, and thus increasing their chances of raising more young.
[Song of Orchard Oriole]
Find more about trans-Gulf migration at BirdNote.org. I’m Mary McCann.
Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Orchard Oriole song recorded by G.F. Budney. Tennessee Warbler [calls recorded by B. Clock. Song of Tennessee Warbler by  M. Medler.
Wind #2 and rain #12 Nature SFX Essentials recorded by Gordon Hempton of QuietPlanet.com
BirdNote’s theme music was composed and played by Nancy Rumbel and John Kessler.
Producer: John Kessler
Executive Producer: Chris Peterson
© 2014 Tune In to Nature.org April 2014 Narrator: Mary McCann.
ID# 041707transgulf2-2KPLU migration-06b
Quote from: Weidensaul, Scott. Living on the Wind: Across the Hemisphere with Migratory Birds. New York: North Point Press, 1999, p. 252.