It was another pretty good week for migration. Those couple of days of
southerly winds brought in another batch of migrants. Along the Gulf
coast from Texas to Alabama, people were reporting lots of Blue-gray
Gnatcatchers, as well as Yellow-throated Warblers, Black-and-white Warblers,
Northern Parulas, Common Yellowthroats, White-eyed Vireos, and the first
Great-crested Flycatcher of the season. Here in the southeastern US,
the first Louisiana Waterthrushes and Blue-headed Vireos were seen (one
of the vireos was in my back yard on Saturday!). The southerly winds
allowed some of those birds to make it fairly far north. Tree Swallows,
Barn Swallows, Louisiana Waterthrushes and Blue-headed Vireos were all
seen in Ohio, Missouri, West Virginia, and Washington, DC.
Things were similar out west. Birders in New Mexico, Arizona, and California
all reported the first Bell's Vireos and Ash-throated Flycatchers, along
with Western Kingbirds, Wilson's Warblers, Yellow Warblers, Lucy's Warblers,
Bullock's Orioles, Violet-green Swallows, and Rufus Hummingbirds. As
in the east, the southerly winds allowed many migrants to fly pretty
far north. One birder near Tacoma, Washington reported over 300 Violet-green
and Northern Rough-winged Swallows, and had 10 Rufus Hummingbirds at
his feeders!
What to Expect This Week
This week's weather map is a little complicated. Take a look:
Right now, a cold front is bringing heavy rain to
the central US and Texas. That, along with northerly winds behind
the front, will prevent migrants from flying for the next couple
of days.
As that front moves east, it is expected to stall,
which will bring rainy weather to the southeastern US for the next
few days. They are forecasting rain here in Tennessee Wednesday through
Saturday.
While the rain is predicted to end a couple of days earlier in the
Northeast, it will be turning colder. All of this means birds will
really be grounded for a while.
With
the increase in migration we are seeing, this prolonged spell of
bad weather could result in the first fallouts
of the season. Many
birds arriving from the tropics are exhausted. (It takes about
18 hours non-stop for a bird to fly across the Gulf of Mexico!)
If they
encounter
rain or headwinds, it is more than they can handle and they land
very quickly and in large numbers. To someone on the ground, it
looks like
the birds are "falling out" of the sky, hence the name
of the phenomenon. A fallout is a very impressive sight to see.
In the
western US, another front is moving into the Northwest. All those
swallows near Tacoma will be staying a while. The Southwest, however,
will remain warm and dry, so people can expect more waves of migrants
to come in.
It
looks like migration is well underway, with lots more to come. Get
out there and enjoy it!
Take Care.
David Aborn North
Chickamauga Creek Conservancy
Chattanooga, TN