Weather and Songbird Migration: March 22, 2017
By Dr. David Aborn

Spring Has Officially Arrived and the Birds Seem to Know It!
   
 
 
Cape May warbler
Cape May warbler
S.Leckie/(CC BY-NC-ND 2.0)

 
 
 
Cliff swallow
Cliff swallow
KSchneider/CC BY-NC 2.0
 
 
   
 
 
Weather Map
Weather Map
   
   
   
Ornithologist Dr. David Aborn  
   

Dear Journey North,

After some weekend rain, much of the eastern U.S. has had southerly winds the past few days, as I mentioned in last week’s report. Birds have taken advantage of those winds and clear skies, and there has been a lot of migration taking place.

Southerly Winds Bring New Arrivals in the East
New species seen recently include Great-crested Flycatchers, Scissor-tailed fly catchers, Black-capped Vireos, and a Cape May Warbler in Texas, White-eyed Vireos and Chimney Swifts in Louisiana, Ovenbirds, Orchard Orioles, and Prairie Warblers in Florida, and the first Blue-headed Warbler here in Tennessee. The southerly winds helped push some Orchard Orioles into Virginia, and the first Ruby-throated Hummingbirds and Black-and-white Warblers were seen in Illinois!

Western Migrants Streaming In
The western U.S. has also had good flying conditions, and there has been a lot of activity out there as well. In addition to more Lucy’s Warblers, Yellow Warblers, Violet-green Swallows, Western Kingbirds, and Cliff Swallows have been moving through Arizona. In California, Western Kingbirds, Bullock’s Orioles, Wilson’s Warblers, and Orange-crowned Warblers have been seen as far north as San Francisco. As in the east, the southerly winds pushed Barn Swallows and Lucy’s Warblers into Nevada, and Rufus Hummingbirds, Common Yellowthroats, Western Kingbirds, and Orange-crowned Warblers have been able to make all the way to Oregon!

Fallout Forecast
What does the coming week look like? If you look at the map, there is a cold front that is moving across the eastern U.S. It is not a strong front, so it will bring rain and storms, but not very strong north winds behind it. Migrants may be grounded for a couple of days, but by the end of the week they should be able to head north again. You can also see that winds in the southwest are coming from the south, so migrants will enjoy another day or two of good flying.

However, you will also notice that there is another front coming in off the Pacific. This is a stronger front, and is predicted to bring big storms as it moves across the country. The strong storms combined with the increased migration activity mean that we may see our first fallouts of the season. Many birds cross the Gulf of Mexico during migration. The crossing is a 1,500 mile, 18-hour non-stop flight. When these birds reach the Gulf Coast, they are already exhausted. If they encounter rain or headwinds, it makes flying even more difficult, so they quickly land in very large numbers -- hence the term "fallout." Birders always look for fallouts because they can see large numbers of a wide variety of species. I have seen fallouts myself, and they are quite spectacular. Birds are on the move, so get out there and see what you can find!

Take care,

  • David Aborn
    North Chickamauga Creek Conservancy
    Chattanooga, TN
Next Update: March 29, 2017