Winds were clearly not favorable for migration last night, as those at the surface were from the SW at 5kts, and those aloft were even stronger from the same direction. So why the migration event? You tell me! Here’s the radar from 6:00pm last night through 6:00am this morning.

Frames are every 1/2 hour. Click on the thumbnail to view the full-sized animation.

While not a major flight by any means, the movement of birds across the radar clearly overpowered the northbound movement of dust, pollen, etc, as can be seen by looking at the velocity images (you can see a general southbound movement across the radar until just before 6:00am, when the direction shifts back around to the prevailing winds, which indicates the point at which birds landed and the pollen, dust, etc. became the dominant feature being picked up by the radar. Isn’t there a rule about the text within a pair of parentheses not being significantly longer than the sentence it’s meant to support?). Anyway, Since the winds were primarily out of the southwest, I would suspect some displacement to the east, which again would favor coastal migrant traps. The source pool of this event was quite restricted to New Jersey, as the NYC radar showed a significantly lower amount of migration (although that which was moving, was headed straight for Sandy Hook, a good bet for this morning). I’d be very interested in hearing from anyone who was listening to nocturnal flight calls last night- since these birds obviously had to have been strong fliers. Hopefully a combination of nocturnal flight calls and some reports from the morning flight at Cape May will help solve this mystery.

Okay birders: on your mark, get set, BIRD!

Good Birding

David