One fantastic flight!



     It was a Tuesday evening, not much different from any other evening except that it was Sept. 25, 2001, right in the middle of fall songbird migration season. A cold front had crossed the entire eastern seaboard about 4:00 PM, EDT that afternoon. In the Western Hemisphere, passage of a cold front usually means wind circulation patterns that produce NW winds, that is, winds that blow from the NW to the SE. NW winds are ideal migration conditions for birds making their way south for winter because they give birds a little push, which can save them energy. 
     By sunset, winds along the East coast were blowing from the NW at 5-15 mph, perfect conditions for a songbird migration event! True to form, migration began about 30 minutes after sunset. By 11:00 PM, EDT, the DIX NEXRAD detected a major bird migration event, with maximum reflectivity reaching 33 dBZ, as shown by the base reflectivity image above. Targets were generally traveling at 26-36 knots, well above the wind speeds, suggesting the echoes detected by NEXRAD were birds.
     On the night of Sept. 25th, five of our six flight call detection stations recorded 3141 flight calls from at least 15 species. The Cape May NWR, Two-Mile Beach site recorded an astounding 2099 calls. Of these, 51% (1078) were from just three species, American Redstart (Setaphaga ruticilla), Common Yellowthroat (Geothlypis trichla), and Northern Parula (Parula americana). Northern Parula calls were an amazing 25% (531) of all calls recorded at the Two-Mile Beach station. Other notable species recorded were Black-throated Blue Warblers (Dendroica caerulescens, 118), Palm Warblers (Dendroica palmarum, 109), Black-and-white Warblers (Mniotilta varia, 43), and Savannah Sparrows (Passerculus sandwichensis, 42).
   (Click on the sonogram to hear the calls).