Weather and Songbird Migration: March 28, 2012
Dr. David Aborn, ornithologist
Dr. David Aborn

Dear Students:

As we end the month of March, spring bird migration rolls on! At my study site at Greenway Farms, Blue-gray gnatcatchers have arrived in full force, and I also saw my first Purple Martins, Barn Swallows, a Black-throated-green Warbler, House Wren, and White-eyed Vireo. Some of the Tree Swallows that arrived a couple of weeks ago are already starting to lay eggs!

A Steady Stream of Migrants Pushing North
The generally clear skies and southerly winds over the past week allowed a steady stream of migrants to make their way over a good portion of the country. Once again, Louisiana saw March Madness, not just because they are hosting the NCAA Men's Basketball championship, but because they had another great week of migration! Specifically, Grand Isle on the Gulf Coast boasted 15 species of warblers this week, including the first Swainson's Warblers, Kentucky Warblers, and Ovenbirds of the spring, along with the first Wood Thrushes and Gray Catbirds. Birders in Alabama also did pretty well, seeing Summer Tanagers, More Black-and-white Warblers, Worm-eating Warblers, Hooded Warblers, and Black-throated-green Warblers.

Southerly winds helped push migrants fairly far north, with Yellow-throated Warblers arriving in Oklahoma, Missouri, and Ohio, and gnatcatchers were seen in Illinois. Birders in Ohio also reported Northern Rough-winged Swallows, Blue-headed Vireos, and a Hooded Warbler. The Hooded Warbler was seen on March 25th, and that is the earliest date hoodeds have ever been seen in the state (the previous record was March 28th)!

Birding was just as good out West. The first Black-headed Grosbeaks and Violet-green Swallows arrived in California, along with Barn Swallows, Cliff Swallows, Purple Martins, Bullock's Orioles, Cassin's Vireos, Yellow Warblers, and Lucy's Warblers. In Arizona, birders have been treated to Black-chinned Hummingbirds, Vermillion Flycatchers, Cassin's Kingbirds, Bell's Vireos, Scott's Orioles, Yellow Warblers, and Lucy's Warblers. Just as in the east, the southerly winds have allowed western migrants to make quite a bit of progress, with Violet-green Swallows, Barn Swallows, and hundreds of Tree Swallows arriving in Nevada, and Northern Rough-winged Swallows making it as far as Oregon!

What Can We Expect This Week?
You should be familiar enough with weather maps that I will give you a minute to look this week's map over and figure out what migration will be like. TICK-TOCK, TICK-TOCK, TICK-TOCK, TICK-TOCK…time's up!

  • You should have seen that cold front draped across the middle of the country, but at the same time there is no rain associated with it, and the north winds behind it are not very strong. This is very similar to what happened last week.
  • As the front moves east, it may pick some moisture from the Gulf of Mexico, which will create some rain, but for the most part birds will have more good flying weather across the country.
  • People in the northern US should keep their eyes open for some of the species I mentioned this week, and people in the southern US should expect more arrivals from the tropics.
  • I have seen some long-range forecasts that predict some significantly cooler weather for the first part of April, so that could mean some of the first good fallouts of the season. We can only hope!

Take Care.

David Aborn
North Chickamauga Creek Conservancy
Chattanooga, TN