March 28, 2007
Dr. David Aborn

Dear Students:

Well, migration is starting to pick up. The front that moved across the country during the end of last week and over the weekend produced a few small fallouts. Numbers were not very big, but there was a good diversity.
On Thursday and Friday, Louisiana had Louisiana Waterthrushes (how appropriate!), Blue-gray Gnatcatchers, Northern Parulas, Prothonotary Warblers, Hooded Warblers, Black-throated-green Warblers, White-eyed Vireos, a Warbling Vireo, and some very early Yellow-billed Cuckoos. Florida reported many of the same species a couple of days later, plus an Ovenbird.

Cuckoos and Caterpillars
Like Louisiana, birders in Florida reported several early cuckoos. I am wondering (and so are many others) why cuckoo migration is off to such an early start. I have noticed here in Tennessee that the tent caterpillars are out early this year, and people in other states have noticed the same thing. Cuckoos LOVE tent caterpillars, and while there is no way a cuckoo in the tropics could know what tent caterpillars are doing up here, it is an interesting coincidence.

Migrants On the Move in the East: Quieter in the West
A few days after the front passed, the high-pressure area moved east, bringing southerly winds behind it. (It was 88 here on Sunday!). That allowed many migrants to leave the Gulf coast and head north. Missouri reported parulas, waterthrushes, and a Prairie Warbler in the St. Louis area, while Washington, DC had an Eastern Kingbird, some Baltimore Orioles, and Indigo Buntings. The swallows that have been around many places the past couple of weeks have made it as far north as Massachusetts and Ohio.

Here in Tennessee, I saw my first non-swallow migrants of the season at my study site yesterday. I had a couple of Blue-gray Gnatcatchers and a Black-and-white Warbler. (For the past several years I have been studying migrants in an urban park to see if urban greenspaces provide the food, shelter, and other requirements migrants need during migration. As the world becomes more urbanized, we need to understand it impacts wildlife and what we can do improve conditions for that wildlife, including migratory birds.) While I had just a couple of migrants, west Tennessee did much better. People in Jackson, TN reported gnatcatchers, black-and-whites, parulas, waterthrushes, White-eyed Vireos, Yellow-throated Vireos, and Blue-headed Vireos.

Things were pretty quiet out west. Orchard Orioles and Baltimore Orioles were seen in California, Vermillion Flycatchers, Lucy's Warblers, and Painted Redstarts were seen in New Mexico, and swallows have made it up to Oregon.

So will this week bring more migrants?

  • That high pressure area is stuck over much of the eastern US. This means southerly winds will continue for another couple of days. Southerly winds will allow migrants that are around to continue north, and enable a steady stream of migrants to continue arriving from the tropics.
  • It doesn't look there will be any fallouts for a few days, but many places should see an increase in the diversity of migrants in their area.
  • Another cold front is over the middle of the country. By the end of the week or the weekend it should bring rain and northerly winds that will force migrants to land. There could be some good sightings, so keep a sharp eye out!

Happy Birding!

David Aborn
North Chickamauga Creek Conservancy
Chattanooga, TN