Spring is a time of boom and bust migration here in New Orleans. According to reports, there is a little "boom" happening today in the Couturie Forest on Harrison Avenue in City Park- the city's premier migrant trap. James Beck reported today that he and a handful of companions found 15 warbler species, accompanied by numbers of other passage migrant species, including 20+ each of Red-eyed Vireo, Great Crested Flycatcher, Scarlet and Summer Tanagers, Rose-breasted Grosbeak, and Indigo Bunting. Warblers were let by 15 Bay-breasted, 12 Tennessee, and 3 of the hard-to-find Cerulean and one harder-to-find "Brewster'" Warbler (Golden-winged x Blue-winged hybrid).
Because winds are still from the northerly half of the compass, chances are that many or most of these birds will hang tight and still be there tomorrow- continuing migration would require departure into a head wind. All these species migrate at night. If you go, focus on both the live oaks and whatever fruiting mulberries you can find in more open sunlit areas.
This fallout is a puzzling. At first glance it appears sensible- we know cold fronts precipitate fallouts by inducing birds to stopover instead of passing over us, and one came through last night. However, this front was still hours away when the birds would have arrived across the Gulf yesterday. This arrival is typically around mid afternoon, and the front didn't reach us until around 3 AM- about 12 hours too late to hit the birds with a headwind and induce them to ground. There was no rain ahead of the front, so that couldn't have caused them to stop. Could it have intercepted last night's flight instead? No- James reported the fallout as already underway at 930 am, before birds from last night's flight across the Gulf should have reached us.
Just when you think you have migration figured out! Sheesh.
Peter
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