Songbird migration is starting. Dr. Aborn begins with a report from an important wintering ground and his primer on weather and migration.

Dear Journey North,
It's time to begin my reports about spring songbird migration, especially since the groundhog predicted an early spring for a change (at least that's what our local groundhog, Chattanooga Chuck, said)! There are already signs of spring. Robins have been singing here since January 15th, and Song Sparrows and cardinals weren't far behind. Best of all, it won't be long before migrants start arriving from their wintering grounds in the tropics.

In fact, the earliest migrants that arrive here, Tree Swallows, showed up here about 2 weeks ago! Before you know it, the country will be overrun with warblers, vireos, tanagers, thrushes, and other migrants coming up from their tropical wintering grounds.

Speaking of their wintering grounds, I just returned from a week in Cuba; a wonderful country that is an important wintering area for many migrants. The most numerous are Palm Warblers, American Redstarts, Blue-gray Gnatcatchers, and Black-and-white Warblers, but there are also lots of Common Yellowthroats, Black-throated-blue Warblers, and Northern Parulas as well. But before I can starting talking to you about songbird migration, we have some work to do, so let's get started!

Weather and Migration
Songbird migration is very dependent on weather conditions, so in order to understand when and where songbird migration may occur, you need to know how to read a weather map.

Each week, I will be showing you the map for that week's weather, and helping you predict who might see lots of birds arriving. Then the next week, I will report on bird sightings from all over the country and see if the predictions were correct. Let's get started with my primer on how to read a weather map and how weather affects bird migration!

• Primer

What Will This Week's Weather Bring?
A warm front is bringing up warm moist air to much of the eastern U.S., and there is a lot of rain with it. Even though the winds are from the south, the rain would keep most migrants on the ground. Behind the warm front is a cold front that will be bringing more rain and strong storms, along with north winds, over the central and eastern U.S. over the next few days, and that will keep migrants grounded. A couple of days after that front moves past, the high pressure behind it will provide clear skies, and the winds will shift back to the south, finally allowing birds to get on their way again.

Stay tuned!
It is too early for a lot of migrants to be arriving, but some of the early birds may still come in, and next week I will let you know if any of them are being seen!

Take care,

• David Aborn
  North Chickamauga Creek Conservancy
  Chattanooga, TN