Friday, April 28, 2006

Moving with the wind...


(click on image for larger version)

There is moderate bird migration occurring tonight (April 27/28) throughout Texas and the Midwest. It's interesting to correlate the NEXRAD image (below) with the wind direction/intensity map (above) to see how the birds favor a tail wind to conserve their energy expenditure during migration. As you look east and the arrows indicate wind coming from the north, bird activity drastically decreases over the same area.


(click on image for larger version)

Image: Full US NEXRAD

There are undoubtedly millions of birds on the move, but it should get more intense soon (I'll display the maps here in the forthcoming weeks). However, with this particular level of activity I'll expect to see new arrivals in Pheasant Branch Conservancy later on this morning (yeah, I'm up at 3:00 a.m. as I type this), but probably not high numbers. Yesterday during a Madison Audubon field trip, we only had 2 Yellow-rumped Warblers, a single Black-and-white Warbler and a smattering of Ruby-crowned Kinglets in addition to a few dozen resident bird species.