Today's News
A/CPB
Cerulean Warbler David Aborn
Thousands of Songbirds Land After Storm
Last Saturday, April 26th, Baltimore Orioles were among the masses of songbirds grounded in Texas when they encountered a storm after crossing the Gulf of Mexico. "Probably the most extensive grounding of birds this decade," said John Whittle of the Texas-based Golden Triangle Audubon Society. "There were hundreds of birds in any given tree, and a great diversity of species," said Steve Astrich of Houston. "I counted over 1,000 Catbirds in a single day, and several times was able to count 50+ birds without turning my head. In just 8 hours I saw 27 species of warblers!"Here are first-hand accounts from observers:
Hats off to our weather correspondent David Aborn for calling this one! Here is his prediction from last week's weather report: "A strong storm system in the northwest is expected to pass through Texas on Friday. It will bring bad flying weather for birds, so this weekend or early next week should have lots of migrants." David describes last the Texas fallout below, and gives this week's weather forecast. These maps help tell last Saturday's story:
April 26, 1997
| Route Across Gulf | Satellite View | Weather Map |
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| Under good conditions, the trip across the Gulf of Mexico takes 18 hours. It can take 24 hours of non-stop flying to cross with headwinds or bad weather, according to Dr. David Aborn. | The skies were clear when the songbirds left the Yucatan Peninsula on Friday night, April 25th. They remained clear most of the way across the Gulf of Mexico, until approaching the Texas Coast. | The birds flew on the front side of this low pressure system, with east winds. Severe thunderstorms along the Texas & Louisiana coasts grounded many thousands of birds. |
| To: | Journey North |
| From: | David Aborn |
| Date: | May 1, 1997 |
Dear Students,
"What a week this was! That storm system I mentioned passed through this area
over the weekend, but it moved very slowly. The winds and rain began Friday
morning, and did not end until Sunday morning. This meant that migration
weather was very poor for that whole time, so LOTS of birds that had just
finished their exhausting flight across the Gulf of Mexico were forced to
land.
Wood Thrush USFWS
"All along the Texas coast, people were reporting the highest number of
birds seen in 10 years. The numbers were in the thousands, and there were 33
species of warblers seen, along with MANY thrushes and tanagers. Many more
birds could not make it to land and died, one of the many hazards of
migration.
"One person commented that this weekend's storm was bad for many bird populations, because many songbird populations are declining. While it is true that many populations are in decline, and that storms can sometimes kill birds by the thousands, in my opinion that statement is an exaggeration. Songbird populations are not so low that one storm will have any lasting effects. Events like this weekend have been occurring for thousands of years, and are part of the natural process of migration and Nature. I'm still glad, however, that someone is concerned enough about the declines to be thinking about the future of songbirds and migration.
"What is the reason for risking trans-Gulf migration? Crossing time. They reach the breeding grounds faster by going across, even though it is riskier. The shortest distance across the Gulf (Yucatan to New Orleans) is 500 miles. Under good conditions, it takes migrants about 18 hours to cross. It can take 24 hour of non-stop flying to cross with headwinds or bad weather. Most migrants arrive along the Gulf coast between 10:00 AM and 2:00 PM, having flown through the night. (Some birds do go around the Gulf in the spring, especially those that breed in the western U.S. However, most of the eastern breeding birds go across the Gulf.)
"I went out Sunday afternoon here in central Texas. The wind was from the north at 15-20 mph. It was not as spectacular, but there were still plenty of birds, including LOTS of Nashville Warblers, Black-throated-green Warblers, Solitary Vireos, and Swainson's Thrushes. I also saw the first records this season for Tennessee Wablers, as well as a Red-eyed Vireo, Indigo Bunting, and a Black-throated-blue Warbler. That last bird is very rare around here. On Monday, a female Summer Tanager (another first record for the season) hit the window of the biology building here at Baylor University. Fortunately, she was only stunned and flew away a little while later. Also on Monday, the winds shifted back around to the south, so most of the birds resumed their migration Monday night.
"So what about this week? You guessed it, another front is coming this way. It is expected to reach here on Friday, with storms ahead of it and north winds
behind it. It should be another good weekend for birding, although this system
is going to move much faster. This means that the winds and rain won't last as
long as last weekend, so the fallout will be good, but not a record-breaker.
Challenge Question: You heard me mention that storms can kill many migrants,
and that a tanager hit a window, what are some of the other hazards migrants
face during their journey north? What about hazards that humans have created
or contributed to?"
Happy Birding!
David A. Aborn
David_Aborn@baylor.edu
The Next Neotropical Migratory Songbird Update Will be Posted on May 8, 1997