Welcome to the first official day of spring! While the weather may not
be able to make up its mind whether it is winter or spring, the birds know
it is time to get moving! The cold front and storm system that brought
so much snow and cold to the northern part of the US didn't force as many
birds
to land as I had anticipated, but as I mentioned last week, it is still
too early for large fallouts. There were still some interesting events,
however.
Radar
Image of Flocks Migrating From Cuba to Florida!
One of the most interesting events occurred before the front reached
the eastern US. Ahead of the system were southerly winds
and no rain, which meant good flying weather for migrants. Even though
warblers,
vireos, and most other migrating songbirds are too small individually
to be picked up by radar, flocks of migrants can be detected. This
radar loop (below) shows birds migrating from Cuba to Florida in advance
of the front!
Click
image to enlarge
Migrating Flocks Show on Radar
Go here to
see a recording of National Weather Service radar in Key West,
Florida. The images show flocks of migrants flying from Cuba to
Florida! The flight occurred during the night of March 14th. The
next two days, March 15th and 16th, birders reported a wide variety
of warblers and vireos throughout the state. These included Hooded
Warblers, Black-and-White Warblers, Yellow-throated Warblers, Northern
Parulas, White-eyed Vireos, and Red-eyed Vireos.
Migrants Moving In Farther
west, Texas had been experiencing several days of rain as a low pressure
area sat over the state. When the system moved east
and skies cleared, migrants moved in. The first Black-throated-green
Warblers, Yellow-throated Warblers, Black-and-white Warblers, Prothonotary
Warblers, and Louisiana Waterthrushes were seen.
Going even farther west, weather conditions were good for migration
all week, and migrants trickled in from the tropics. Swallows were
still the most common sight, but California also reported an Orchard
Oriole, Rufus and Allen's Hummingbirds, a Plumbeous Vireo, a Tennessee
Warbler, and a Summer Tanager. The first Rufus Hummingbirds and Allen's
Hummingbirds made it into Oregon.
What
Will the Weather Bring this Week?
A
cold front is moving across the eastern half of the country. It
is a weak front, which means
the winds behind it are not strong, and it does not have much rain with
it. Thus, for most of the country, skies will be clear and winds will
be light. This will allow birds in the southern US to fly northward and
birds coming up from the tropics won't find any problems.
Another
front Is moving in off of the Pacific Ocean. This one has more
rain with it, so there could be some small fallouts out West.
I have
still only seen swallows and martins at my study site, but the was
the first report of a Louisiana Waterthrush this week, so I am looking
forward to getting back out there!
Happy
Birding!
David
Aborn
North Chickamauga Creek Conservancy
Chattanooga, TN